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Craniovertebral junction Craniovertebral junction Introduction Introduction EmbryologyEmbryology
AnatomyAnatomyRadiologyRadiology
Anomalies of cvjAnomalies of cvj
Cvj collective term that refers to Cvj collective term that refers to occiputatlasaxisamp supporting occiputatlasaxisamp supporting ligamentsligaments
Its transition between mobile Its transition between mobile cranium amp rigid spinal columncranium amp rigid spinal column
It encloses soft tissue structures It encloses soft tissue structures of the cervicomedullary of the cervicomedullary jn(medulla spinal cordamp lower jn(medulla spinal cordamp lower cranial nerves) cranial nerves)
Embryology and development Embryology and development of cvjof cvj
Development of the cartilaginous cranium amp the adjacent structures begins during the early weeks of intrauterine life
2ndGestational week Mesoderm cells condense in the midline to form notochordalprocess
3rdGestational week
-notochordalprocess invaginatesin bw ectoamp endoderm to form notochord
-dorsal ectoderm thickens to form neural groove which folds fuses amp becomes neural tube
Eampd contdhellipEampd contdhellip
Between 3rdamp 5thweek
-part of mesoderm which lies on either side of notochord (Paraxial mesoderm) gives rise to somites(Segmentation)
-total 42 somitesform at 4thweek -ventromedialportion of somiteis ka
sclerotomewhich forms the vertebral bodies -each sclerotomedifferentiates into a
cranial loosely arranged portion and a caudal compact portion by a fissure ka ldquoFissure
Eampd contdhellipEampd contdhellip
Mesenchymalcells of the fissure condense around the notochord to form the intervertebraldisc
Notochord disappears at the vertebral bodies but persist asnucleus pulposusat disc
The first four sclerotomesdo not follow this course amp fuse to form the occipital bone amp postportionof FM
This membraneousstage is fbstages of chondrificationamp ossification
Out of 4 occipital sclerotomesthe first 2 form basiocciput the III Jugular tuberclesand the IV (Proatlas) form parts of foramen magnum atlas and
Eampd contdhellipEampd contdhellip
PROATLAS divided into the hypocentrum centrumamp the neural arches
-hypocentrumforms the vestigial condylustertiusor anterior tubercle of the clivus
-centrumforms the apex of the dens also forms the apical ligament (AL) of dens (AL may contain notochordaltissuesoka rudimentary IVdisc)
-ventral part of the neural arch forms the ant margin of FM 2 occipital condylesamp the alaramp cruciateligaments
-dorsal part forms paired rostralarticularfacets lateral masses of C1 amp superior portion of the post arch of the atlas
Eampd contdhellipEampd contdhellip
ATLAS no vertebral body amp no IV disc
-major portion formed by first spinal sclerotome -trasitionalvertebra as centrumof sclerotomeis
separated to fuse with the axis body forming the odontoidprocess
-hypocentrumof 1stspinal sclerotomeforms the anterior arch of the atlas
-neural arch of the first spinal sclerotomeforms the inferior portion of the posterior arch of atlas
Eampd contdhellipEampd contdhellip
AXIS develops from 2ndspinal sclerotome
-hypocentrumof 2ndspinal sclerotomedisappears during embryogenesis
-centrumforms the body of the axis vertebra amp neural arch develops into the facets amp the posterior arch of the axis
-At birth odontoidbase is separate from the body of axis by a cartilage which persists until the age of 8 later the center gets ossifiedormay remain separate asOs-odontoidium
-The apical segment is not ossified until 3 years of age at 12 years if fuses with odontoidto form normal odontoid failure leads to Os termin
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Cvj collective term that refers to Cvj collective term that refers to occiputatlasaxisamp supporting occiputatlasaxisamp supporting ligamentsligaments
Its transition between mobile Its transition between mobile cranium amp rigid spinal columncranium amp rigid spinal column
It encloses soft tissue structures It encloses soft tissue structures of the cervicomedullary of the cervicomedullary jn(medulla spinal cordamp lower jn(medulla spinal cordamp lower cranial nerves) cranial nerves)
Embryology and development Embryology and development of cvjof cvj
Development of the cartilaginous cranium amp the adjacent structures begins during the early weeks of intrauterine life
2ndGestational week Mesoderm cells condense in the midline to form notochordalprocess
3rdGestational week
-notochordalprocess invaginatesin bw ectoamp endoderm to form notochord
-dorsal ectoderm thickens to form neural groove which folds fuses amp becomes neural tube
Eampd contdhellipEampd contdhellip
Between 3rdamp 5thweek
-part of mesoderm which lies on either side of notochord (Paraxial mesoderm) gives rise to somites(Segmentation)
-total 42 somitesform at 4thweek -ventromedialportion of somiteis ka
sclerotomewhich forms the vertebral bodies -each sclerotomedifferentiates into a
cranial loosely arranged portion and a caudal compact portion by a fissure ka ldquoFissure
Eampd contdhellipEampd contdhellip
Mesenchymalcells of the fissure condense around the notochord to form the intervertebraldisc
Notochord disappears at the vertebral bodies but persist asnucleus pulposusat disc
The first four sclerotomesdo not follow this course amp fuse to form the occipital bone amp postportionof FM
This membraneousstage is fbstages of chondrificationamp ossification
Out of 4 occipital sclerotomesthe first 2 form basiocciput the III Jugular tuberclesand the IV (Proatlas) form parts of foramen magnum atlas and
Eampd contdhellipEampd contdhellip
PROATLAS divided into the hypocentrum centrumamp the neural arches
-hypocentrumforms the vestigial condylustertiusor anterior tubercle of the clivus
-centrumforms the apex of the dens also forms the apical ligament (AL) of dens (AL may contain notochordaltissuesoka rudimentary IVdisc)
-ventral part of the neural arch forms the ant margin of FM 2 occipital condylesamp the alaramp cruciateligaments
-dorsal part forms paired rostralarticularfacets lateral masses of C1 amp superior portion of the post arch of the atlas
Eampd contdhellipEampd contdhellip
ATLAS no vertebral body amp no IV disc
-major portion formed by first spinal sclerotome -trasitionalvertebra as centrumof sclerotomeis
separated to fuse with the axis body forming the odontoidprocess
-hypocentrumof 1stspinal sclerotomeforms the anterior arch of the atlas
-neural arch of the first spinal sclerotomeforms the inferior portion of the posterior arch of atlas
Eampd contdhellipEampd contdhellip
AXIS develops from 2ndspinal sclerotome
-hypocentrumof 2ndspinal sclerotomedisappears during embryogenesis
-centrumforms the body of the axis vertebra amp neural arch develops into the facets amp the posterior arch of the axis
-At birth odontoidbase is separate from the body of axis by a cartilage which persists until the age of 8 later the center gets ossifiedormay remain separate asOs-odontoidium
-The apical segment is not ossified until 3 years of age at 12 years if fuses with odontoidto form normal odontoid failure leads to Os termin
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Embryology and development Embryology and development of cvjof cvj
Development of the cartilaginous cranium amp the adjacent structures begins during the early weeks of intrauterine life
2ndGestational week Mesoderm cells condense in the midline to form notochordalprocess
3rdGestational week
-notochordalprocess invaginatesin bw ectoamp endoderm to form notochord
-dorsal ectoderm thickens to form neural groove which folds fuses amp becomes neural tube
Eampd contdhellipEampd contdhellip
Between 3rdamp 5thweek
-part of mesoderm which lies on either side of notochord (Paraxial mesoderm) gives rise to somites(Segmentation)
-total 42 somitesform at 4thweek -ventromedialportion of somiteis ka
sclerotomewhich forms the vertebral bodies -each sclerotomedifferentiates into a
cranial loosely arranged portion and a caudal compact portion by a fissure ka ldquoFissure
Eampd contdhellipEampd contdhellip
Mesenchymalcells of the fissure condense around the notochord to form the intervertebraldisc
Notochord disappears at the vertebral bodies but persist asnucleus pulposusat disc
The first four sclerotomesdo not follow this course amp fuse to form the occipital bone amp postportionof FM
This membraneousstage is fbstages of chondrificationamp ossification
Out of 4 occipital sclerotomesthe first 2 form basiocciput the III Jugular tuberclesand the IV (Proatlas) form parts of foramen magnum atlas and
Eampd contdhellipEampd contdhellip
PROATLAS divided into the hypocentrum centrumamp the neural arches
-hypocentrumforms the vestigial condylustertiusor anterior tubercle of the clivus
-centrumforms the apex of the dens also forms the apical ligament (AL) of dens (AL may contain notochordaltissuesoka rudimentary IVdisc)
-ventral part of the neural arch forms the ant margin of FM 2 occipital condylesamp the alaramp cruciateligaments
-dorsal part forms paired rostralarticularfacets lateral masses of C1 amp superior portion of the post arch of the atlas
Eampd contdhellipEampd contdhellip
ATLAS no vertebral body amp no IV disc
-major portion formed by first spinal sclerotome -trasitionalvertebra as centrumof sclerotomeis
separated to fuse with the axis body forming the odontoidprocess
-hypocentrumof 1stspinal sclerotomeforms the anterior arch of the atlas
-neural arch of the first spinal sclerotomeforms the inferior portion of the posterior arch of atlas
Eampd contdhellipEampd contdhellip
AXIS develops from 2ndspinal sclerotome
-hypocentrumof 2ndspinal sclerotomedisappears during embryogenesis
-centrumforms the body of the axis vertebra amp neural arch develops into the facets amp the posterior arch of the axis
-At birth odontoidbase is separate from the body of axis by a cartilage which persists until the age of 8 later the center gets ossifiedormay remain separate asOs-odontoidium
-The apical segment is not ossified until 3 years of age at 12 years if fuses with odontoidto form normal odontoid failure leads to Os termin
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Eampd contdhellipEampd contdhellip
Between 3rdamp 5thweek
-part of mesoderm which lies on either side of notochord (Paraxial mesoderm) gives rise to somites(Segmentation)
-total 42 somitesform at 4thweek -ventromedialportion of somiteis ka
sclerotomewhich forms the vertebral bodies -each sclerotomedifferentiates into a
cranial loosely arranged portion and a caudal compact portion by a fissure ka ldquoFissure
Eampd contdhellipEampd contdhellip
Mesenchymalcells of the fissure condense around the notochord to form the intervertebraldisc
Notochord disappears at the vertebral bodies but persist asnucleus pulposusat disc
The first four sclerotomesdo not follow this course amp fuse to form the occipital bone amp postportionof FM
This membraneousstage is fbstages of chondrificationamp ossification
Out of 4 occipital sclerotomesthe first 2 form basiocciput the III Jugular tuberclesand the IV (Proatlas) form parts of foramen magnum atlas and
Eampd contdhellipEampd contdhellip
PROATLAS divided into the hypocentrum centrumamp the neural arches
-hypocentrumforms the vestigial condylustertiusor anterior tubercle of the clivus
-centrumforms the apex of the dens also forms the apical ligament (AL) of dens (AL may contain notochordaltissuesoka rudimentary IVdisc)
-ventral part of the neural arch forms the ant margin of FM 2 occipital condylesamp the alaramp cruciateligaments
-dorsal part forms paired rostralarticularfacets lateral masses of C1 amp superior portion of the post arch of the atlas
Eampd contdhellipEampd contdhellip
ATLAS no vertebral body amp no IV disc
-major portion formed by first spinal sclerotome -trasitionalvertebra as centrumof sclerotomeis
separated to fuse with the axis body forming the odontoidprocess
-hypocentrumof 1stspinal sclerotomeforms the anterior arch of the atlas
-neural arch of the first spinal sclerotomeforms the inferior portion of the posterior arch of atlas
Eampd contdhellipEampd contdhellip
AXIS develops from 2ndspinal sclerotome
-hypocentrumof 2ndspinal sclerotomedisappears during embryogenesis
-centrumforms the body of the axis vertebra amp neural arch develops into the facets amp the posterior arch of the axis
-At birth odontoidbase is separate from the body of axis by a cartilage which persists until the age of 8 later the center gets ossifiedormay remain separate asOs-odontoidium
-The apical segment is not ossified until 3 years of age at 12 years if fuses with odontoidto form normal odontoid failure leads to Os termin
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Eampd contdhellipEampd contdhellip
Mesenchymalcells of the fissure condense around the notochord to form the intervertebraldisc
Notochord disappears at the vertebral bodies but persist asnucleus pulposusat disc
The first four sclerotomesdo not follow this course amp fuse to form the occipital bone amp postportionof FM
This membraneousstage is fbstages of chondrificationamp ossification
Out of 4 occipital sclerotomesthe first 2 form basiocciput the III Jugular tuberclesand the IV (Proatlas) form parts of foramen magnum atlas and
Eampd contdhellipEampd contdhellip
PROATLAS divided into the hypocentrum centrumamp the neural arches
-hypocentrumforms the vestigial condylustertiusor anterior tubercle of the clivus
-centrumforms the apex of the dens also forms the apical ligament (AL) of dens (AL may contain notochordaltissuesoka rudimentary IVdisc)
-ventral part of the neural arch forms the ant margin of FM 2 occipital condylesamp the alaramp cruciateligaments
-dorsal part forms paired rostralarticularfacets lateral masses of C1 amp superior portion of the post arch of the atlas
Eampd contdhellipEampd contdhellip
ATLAS no vertebral body amp no IV disc
-major portion formed by first spinal sclerotome -trasitionalvertebra as centrumof sclerotomeis
separated to fuse with the axis body forming the odontoidprocess
-hypocentrumof 1stspinal sclerotomeforms the anterior arch of the atlas
-neural arch of the first spinal sclerotomeforms the inferior portion of the posterior arch of atlas
Eampd contdhellipEampd contdhellip
AXIS develops from 2ndspinal sclerotome
-hypocentrumof 2ndspinal sclerotomedisappears during embryogenesis
-centrumforms the body of the axis vertebra amp neural arch develops into the facets amp the posterior arch of the axis
-At birth odontoidbase is separate from the body of axis by a cartilage which persists until the age of 8 later the center gets ossifiedormay remain separate asOs-odontoidium
-The apical segment is not ossified until 3 years of age at 12 years if fuses with odontoidto form normal odontoid failure leads to Os termin
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Eampd contdhellipEampd contdhellip
PROATLAS divided into the hypocentrum centrumamp the neural arches
-hypocentrumforms the vestigial condylustertiusor anterior tubercle of the clivus
-centrumforms the apex of the dens also forms the apical ligament (AL) of dens (AL may contain notochordaltissuesoka rudimentary IVdisc)
-ventral part of the neural arch forms the ant margin of FM 2 occipital condylesamp the alaramp cruciateligaments
-dorsal part forms paired rostralarticularfacets lateral masses of C1 amp superior portion of the post arch of the atlas
Eampd contdhellipEampd contdhellip
ATLAS no vertebral body amp no IV disc
-major portion formed by first spinal sclerotome -trasitionalvertebra as centrumof sclerotomeis
separated to fuse with the axis body forming the odontoidprocess
-hypocentrumof 1stspinal sclerotomeforms the anterior arch of the atlas
-neural arch of the first spinal sclerotomeforms the inferior portion of the posterior arch of atlas
Eampd contdhellipEampd contdhellip
AXIS develops from 2ndspinal sclerotome
-hypocentrumof 2ndspinal sclerotomedisappears during embryogenesis
-centrumforms the body of the axis vertebra amp neural arch develops into the facets amp the posterior arch of the axis
-At birth odontoidbase is separate from the body of axis by a cartilage which persists until the age of 8 later the center gets ossifiedormay remain separate asOs-odontoidium
-The apical segment is not ossified until 3 years of age at 12 years if fuses with odontoidto form normal odontoid failure leads to Os termin
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Eampd contdhellipEampd contdhellip
ATLAS no vertebral body amp no IV disc
-major portion formed by first spinal sclerotome -trasitionalvertebra as centrumof sclerotomeis
separated to fuse with the axis body forming the odontoidprocess
-hypocentrumof 1stspinal sclerotomeforms the anterior arch of the atlas
-neural arch of the first spinal sclerotomeforms the inferior portion of the posterior arch of atlas
Eampd contdhellipEampd contdhellip
AXIS develops from 2ndspinal sclerotome
-hypocentrumof 2ndspinal sclerotomedisappears during embryogenesis
-centrumforms the body of the axis vertebra amp neural arch develops into the facets amp the posterior arch of the axis
-At birth odontoidbase is separate from the body of axis by a cartilage which persists until the age of 8 later the center gets ossifiedormay remain separate asOs-odontoidium
-The apical segment is not ossified until 3 years of age at 12 years if fuses with odontoidto form normal odontoid failure leads to Os termin
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Eampd contdhellipEampd contdhellip
AXIS develops from 2ndspinal sclerotome
-hypocentrumof 2ndspinal sclerotomedisappears during embryogenesis
-centrumforms the body of the axis vertebra amp neural arch develops into the facets amp the posterior arch of the axis
-At birth odontoidbase is separate from the body of axis by a cartilage which persists until the age of 8 later the center gets ossifiedormay remain separate asOs-odontoidium
-The apical segment is not ossified until 3 years of age at 12 years if fuses with odontoidto form normal odontoid failure leads to Os termin
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
AnatomyAnatomy
Articular Articular LigamentousLigamentous MusclesMuscles NeuralNeural LymphaticsLymphatics ArterialArterial venousvenous
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
articulararticular
Upper surfaces of C1 lateral masses are cup-like or concave which fit into the ball amp socket configuration united by articularcapsules surr the AO joint amp by the ant amp post AO membranes
10487084 synovialjoints bw atlas amp axis ndash
2 median ndashfront amp back of dens (Pivot variety) 2 lateral ndashbw opposing articularfacets(Planevariety)
1048708Each joint has its own capsule amp synovialcavity
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
LigamentousLigamentous
atlanto-occipital ligatlanto-occipital lig anterior a-o membraneanterior a-o membrane Posterior a-o membranePosterior a-o membrane Lateral a-o ligLateral a-o ligAtlanto axial ligAtlanto axial lig Ant a-a ligAnt a-a lig Post a-a ligPost a-a lig Transverse lig of atlasTransverse lig of atlas
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Axis-occipital ligAxis-occipital lig Tectorial membTectorial memb Alar ligAlar lig Apical ligApical lig
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
musclesmuscles
Have minor role related to Have minor role related to stabilizationamp do not limit stabilizationamp do not limit movements movements
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
neuralneural
Neural structures related to cvj Neural structures related to cvj caudal portion of brainstcaudal portion of brainstem Cerebellum 4th ventricle amprostral part of
spinal cord Upper cranial amplower cervical
nerves
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Neural contdhellipNeural contdhellip
Lower 4 cn are closely related to cvjLower 4 cn are closely related to cvj 9amp109amp10thth cn arise from medulla(ion)ampinf cn arise from medulla(ion)ampinf
cerebellar peduncle seperated by cerebellar peduncle seperated by dural seathdural seath
Acessory n is only nerve that passes Acessory n is only nerve that passes through foramen magnum has two through foramen magnum has two parts ramus internus amp ramus parts ramus internus amp ramus externusexternus
The C1 C2 and C3 nerves distal to the ganglion divide into dorsal and ventral rami
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
lymphaticslymphatics
The lymphatic drainage of the O-A-A joints is primarily into the retropharyngeal LN amp then into the deep cervical chain
These LNrsquosalso drain the nasopharynxamp hence retrograde infection may affect the synoviallining of the CVJ complex with resultant neck stiffness amp instability
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
vascularvascular
The major arteries related to CVJ are vertebral posteroinferiorcerebellararteries (PICA) and the meningealbranches of the vertebral and external and internal carotid arteries
The venous structures in the region of the FM are divided into three groups
-Extraduralveins(extraspinalamp intraspinalpart) -Intradural(neural) veins amp
-Duralvenous sinuses( superior petrosal marginal amp occipital)
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
kineticskinetics
3 major articulations determine stability and 3 major articulations determine stability and movements at the skull basemovements at the skull base
Nodding or ldquoyes-yesrdquo movements occur at Nodding or ldquoyes-yesrdquo movements occur at atlanto occipital joints atlanto occipital joints
Rotary or no ndashno movements occur at Rotary or no ndashno movements occur at atlanto-axial joints Both atlanto occipital atlanto-axial joints Both atlanto occipital and atlanto axial articulations are involved and atlanto axial articulations are involved in flexion motion Flexion at occipito atlantal in flexion motion Flexion at occipito atlantal joint is 13-15joint is 13-1500 and an additional 10 and an additional 1000 of of motion occurs at atlas articulationmotion occurs at atlas articulation
Rotation of the craniovertebral complex Rotation of the craniovertebral complex occurs only at atlas ndash axis jointoccurs only at atlas ndash axis joint
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Kinetics contdhellipKinetics contdhellip
The articular surfaces of atlanto- axial The articular surfaces of atlanto- axial complex are convex with horizontal complex are convex with horizontal orientationorientation
Allows maximum mobility at the cost of Allows maximum mobility at the cost of stability Thus the stabilizing effect of stability Thus the stabilizing effect of upper is essential upper is essential
Cervical musculature not fully developed Cervical musculature not fully developed until age 8 allowing for abnormal until age 8 allowing for abnormal atlanto- axial rotations atlanto- axial rotations
Atlanto-axial rotation is maximum at 45Atlanto-axial rotation is maximum at 4500 Beyond this an interlocking of the lateral Beyond this an interlocking of the lateral mass of the atlas over the superior mass of the atlas over the superior surface of the axis vertebra occurs surface of the axis vertebra occurs
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Kinetics contdhellipKinetics contdhellip
Lateral rotation of neck possible is Lateral rotation of neck possible is 909000 half of which occurs above C2 half of which occurs above C2 level and the remainder in lower level and the remainder in lower cervical spine cervical spine
Odontoid process is of central Odontoid process is of central importance in the radiology of importance in the radiology of craniovertebral lesions Atlanto- axial craniovertebral lesions Atlanto- axial joints allow less flexion-extension joints allow less flexion-extension motion than rotationmotion than rotation
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Radiological evaluation of cvjRadiological evaluation of cvj
Conventional digital Conventional digital radiography radiography
Lateral viewLateral view Translateral view of skull Translateral view of skull
including cervical spine with full including cervical spine with full flexion and extension flexion and extension
Open mouth viewOpen mouth view Conventional tomographyConventional tomography
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Ct(ncctamp3dct)Ct(ncctamp3dct) Mriampdynamic mriMriampdynamic mri Dynamic MRI uses sagittal Dynamic MRI uses sagittal
sections in active flexion and sections in active flexion and extension- better evaluation of extension- better evaluation of AAD and ligamental changes in AAD and ligamental changes in AAD AAD
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
craniometrycraniometry
Craniometryof the CVJ uses a series of lines planes amp angles to define the normal anatomic relationships of the CVJ
These measurements can be taken on plain Xrays3DCT or on MRI
No single measurement is helpful
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
LATERAL PROJECTION OF SKULL X-RAY
bull Palatondashoccipital (Chamberlainrsquos line) (gt5mm) bull Palatondashsuboccipitalline (McGregor line) ( gt 7mm) bull Foramen magnum line (McRae line) (Tip of dens below this line)
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Chamberlanrsquos line(palato-Chamberlanrsquos line(palato-occipital)occipital)
Line joining posterior tip of hard palate to the posterior rim of foramen magnum Odontoid tip usually within 5 mm above this line Disadvantage - variability of posterior rim of foramen magnum
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Mcgregors line(palato-Mcgregors line(palato-suboccipital line)suboccipital line)
Line joining lowest point of occipital bone to the posterior tip of hard palate Odontoid tip should be within 7 mm above this line It appears to be most accurate and reproducible
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Wakenheimclival line(basilar)Wakenheimclival line(basilar)Line representing the downward prolongation of clivus along its posterior surface Dens should lie anterior and caudal to this tangent If clivus concave convex baseline by connecting a point just below the posterior clinoid process to basion Basilar line forms an angle with a line along the posterior surface of axis ranging from 150-1800 (in flexion and extension ) Canal compromise is present at angle lt 1500
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Kalus index(ht of posterior Kalus index(ht of posterior cranial fossa)cranial fossa) Perpendicular line drawn from Perpendicular line drawn from
tip of odontoid process plane of tip of odontoid process plane of foramen magnum to Twinningrsquos foramen magnum to Twinningrsquos lineline
average - 35mm lt 30 mm is average - 35mm lt 30 mm is basilar invagination (BI) basilar invagination (BI)
Twinning line- joins internal Twinning line- joins internal occipital protuberance to occipital protuberance to tuberculum sellae)tuberculum sellae)
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Twinningrsquos Point- Falls normally in Twinningrsquos Point- Falls normally in center of 4th ventricle Intersection center of 4th ventricle Intersection of Twinnings line amp Klausrsquo vertical is of Twinnings line amp Klausrsquo vertical is situated upto 10 mm anterior to the situated upto 10 mm anterior to the midpoint of Twinningrsquos linemidpoint of Twinningrsquos line
Klausrsquo index is concerned only with Klausrsquo index is concerned only with structures in midline of skull structures in midline of skull
Possesses specific value in the Possesses specific value in the diagnosis of basilar hypoplasia the diagnosis of basilar hypoplasia the main abnormality in basilar main abnormality in basilar invaginationinvagination
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Mcray line(plane of foramen Mcray line(plane of foramen magnum)magnum)
line from basion to opisthion Normal 33 mm Symptomatic disease associated with value below 20 mm Stenosis widening of foramen magnum is a diagnosis that depends on the ratio of sagittal diagmeter of foramen magnum to that at the level of atlas
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Basal angleBasal angle
Angle between the lines drawn from nasion to tuberculum sellae and tuberculum sellae to basion Normal 124 -140 any widening is called platybasia
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Boogards line amp angleBoogards line amp angle
Boogardrsquos line connects nasion to Boogardrsquos line connects nasion to opisthion Boogardrsquos angle opisthion Boogardrsquos angle McRaersquos line drawn first Second McRaersquos line drawn first Second line drawn from dorsum sellae to line drawn from dorsum sellae to basion along the plane of clivus basion along the plane of clivus Angle formed between these 2 lines Angle formed between these 2 lines is measured Average 122is measured Average 12200 both both measurement will be altered in measurement will be altered in basilar impression- the basion will basilar impression- the basion will be above Boogardrsquos line and angle be above Boogardrsquos line and angle will be greater than 135will be greater than 13500
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Atlanto temporomandibular Atlanto temporomandibular indexindex
(Normal 30 (Normal 30 ++ mm lt 10 mm mm lt 10 mm in BI in BI
Distance between superior Distance between superior edge of anterior arch of edge of anterior arch of atlas and the highest point atlas and the highest point of temporomandibular of temporomandibular interspace Regarded as interspace Regarded as one of the best criteria of one of the best criteria of BI since it defines the BI since it defines the position of foramen position of foramen magnum relative to a magnum relative to a lateral lying structure which lateral lying structure which is not involved in the is not involved in the invagination invagination
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Spino lamellarlineSpino lamellarline
Line drawn from interoccipital Line drawn from interoccipital ridge above and down along the ridge above and down along the fused spinous process of C2 fused spinous process of C2 and C3 Normally it should and C3 Normally it should intersect posterior arch of atlas intersect posterior arch of atlas If atlas is fused post arch is If atlas is fused post arch is anterior to the line posterior anterior to the line posterior compression of spinal cord may compression of spinal cord may occur occur
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Frontal projectionFrontal projection
Bidigastric line (FischgoldBidigastric line (Fischgold Line joining tips of mastoid Line joining tips of mastoid
processes and normally passes processes and normally passes through atlanto occipital interspace through atlanto occipital interspace Tip of odontoid will be with in 1 cm Tip of odontoid will be with in 1 cm above this line Disadvantage ndash above this line Disadvantage ndash Mastoid tips vary greatly in Mastoid tips vary greatly in development if mastoid tips are development if mastoid tips are well defined odontoid process is well defined odontoid process is blurred and vice versa blurred and vice versa
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Condylar angle (Schmidt ndash Condylar angle (Schmidt ndash Fisher angleFisher angle angle formed by intersection of angle formed by intersection of
2 lines drawn of atlanto- 2 lines drawn of atlanto- condylar interspace Normal condylar interspace Normal 135135+ + 50 angle wider in condylar 50 angle wider in condylar hypoplasiahypoplasia
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Classification of abnormalities Classification of abnormalities of of CVJCVJ Congenital Anomalies and Congenital Anomalies and
Malformations Malformations Malformations of occipital bone Malformations of occipital bone Manifestations of occipital vertebra Manifestations of occipital vertebra
Clivus segmentations Clivus segmentations Remnants around foramen magnum Remnants around foramen magnum Atlas variant Atlas variant
Basilar invagination Basilar invagination Condylar hypoplasia Condylar hypoplasia Assimilation of atlasAssimilation of atlas
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
IIII Malfomations of atlas Malfomations of atlas Assimilation Of Atlas Assimilation Of Atlas Atlanto axial fusion Atlanto axial fusion Aplasia of atlas archesAplasia of atlas arches
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
IIIIII Malfomations of axis Malfomations of axis Irregular atlantoaxial segmentation Irregular atlantoaxial segmentation Dens dysplasias Dens dysplasias Ossiculum terminale persistans Ossiculum terminale persistans Os Odontoideum Os Odontoideum Hypoplasia ndash Aplasia Hypoplasia ndash Aplasia Segmentaion failure of C2- C3Segmentaion failure of C2- C3
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Abnormalities of foramen Abnormalities of foramen magnum magnum Secondary basilar invagination ndash Secondary basilar invagination ndash
eg Pagetrsquos disease eg Pagetrsquos disease Osteomalacia Rheumatoid Osteomalacia Rheumatoid cranial settling renal resistance cranial settling renal resistance rickets rickets
Foraminal stenosis ndash eg Foraminal stenosis ndash eg Achondroplasia Achondroplasia
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Atlanto axial instability Atlanto axial instability Traumatic occipitoatlantal and atlanto Traumatic occipitoatlantal and atlanto
axial dislocations Os odontoideum axial dislocations Os odontoideum Downrsquos syndrome Downrsquos syndrome Infections ndash eg Griselrsquos syndromeInfections ndash eg Griselrsquos syndrome Inflammatory ndash eg rheumatoid arthritis Inflammatory ndash eg rheumatoid arthritis Tumors- eg Neurofibromatosis Tumors- eg Neurofibromatosis
Syringomyelia Syringomyelia Errors of metabolism ndash eg Morquios Errors of metabolism ndash eg Morquios
syndromesyndrome
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Multiple anomalies frequently Multiple anomalies frequently seen Common combination seen Common combination were AAD with occipitalisation of were AAD with occipitalisation of atlas BI with chiari atlas BI with chiari malformation and BI with malformation and BI with occipitalisation of atlasoccipitalisation of atlas Miscellaneous ndash eg Fatal Miscellaneous ndash eg Fatal
Warfarin syndrome Convadi Warfarin syndrome Convadi syndromesyndrome
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Anomalies of occiputAnomalies of occiput
Condylar hypoplasiaCondylar hypoplasia In condylar hypoplasia the occipital condyles are underdeveloped and have a flattened appearance leading to BI (violation of the Chamberlain line) and widening of the atlantooccipitaljoint axis angle
The lateral masses of the atlas may be fused to the hypoplasticcondyles further accentuating the BI
Condylarhypoplasialimits or may even abolish movements at the A-O joint
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Kippel feil syndromeKippel feil syndrome
Due to failure of the normal segmentation of cervical somitesduring the third and eighth weeks of gestation
1048708Classic triad of low posterior hair line short neck and limited neck ROM found in less than 50 of cases
1048708The most consistent finding is limitation of neck motion
1048708Generally flexion and extension are better preserved than side-bending and rotation
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Type 1Cervical spine fusion in which elements of many vertebrae are incorporated into a single block
Type 2Cervical spine fusion in which there is failure of complete segmentation at only one or two cervical levels and may include an occipito-atlantalfusion
Type 3Type 1 or type 2 fusion with co-existing segmentation errors in the lower dorsal or lumbar spine
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Scoliosis-Up to 60 have gt15 degrees curve Genito-urinary-up to 65Most common is absence
of kidney Sprengelsdeformity-approx 35 Cardio-pulmonary-5-15 most commonly VSD Deafness-30 all types MC mixed Sykinesis-Mirror motions have been described in up
to 20 of patients under the age of 5 Cranio-cervical abnormalities (25)-Includes C1-
C2 hypermobilityand instability BIChiariI malformation diastematomyelia amp syringomyelia
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Anomalies of occiput contdhellipAnomalies of occiput contdhellip
Terms basilar invagination Terms basilar invagination basilar impression and basilar impression and platybasia are not synonymous platybasia are not synonymous and require definitionand require definition
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Basilar invaginationBasilar invagination
Basilar invaginationBasilar invagination ndash is a ndash is a developmental defect implying prolapse developmental defect implying prolapse of vertebral column into the skull base It of vertebral column into the skull base It is frequently associated with such is frequently associated with such developmental bony anomalies of the developmental bony anomalies of the region as occipitalization of atlas region as occipitalization of atlas defective fusion of arch and block defective fusion of arch and block vertebral malformationsvertebral malformations
There are two types of basilar invagination primary invagination which is developmental and more common and secondary invagination which is acquired
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Topographic types of BI Anterior BI hypoplasiaof the basilar
process of the occipital bone BI of the occipital
condyles(ParamedianBI)ndashCondylarhypoplasia
BI in the lateral condylararea Posterior BI posterior margin of the
FM is invaginated Unilateral BI GeneralisedBI
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
SIGNS SYMPTOMS usually occur in 2ndor 3rddecade Short neck(78)torticollis (68) ssof associated ACM (cerebellaramp vestibular
disturbances) amp syringomyelia(25 to 35) Motor amp sensory disturbances (85) Lower cranial nerves involvement Headache amp pain in the nape of neck (greater occipital N) ssof raised ICP (HCP) due to posterior encroachment
which causes blockage of aqueduct of sylvius Compression of cerebellum amp vestibular apparatus
leading to vertical or lateral nystagmus(65) (not due to direct pressure from post rim of FM but rather due to a thickened band of dura)
Vertebral artery insufficiency ss
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Basilar impression(sec basillar Basilar impression(sec basillar invagination)invagination) Basilar impression refers to
secondary or acquired forms of BI amp is due to softening of the bone amp is seen in conditions such as rickets hyperparathyroidism osteogenesis imperfecta Paget disease neurofibromatosis skeletal dysplasias and RA amp infection producing bone destruction with or without ligamentous laxity
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Assimilation of atlas or Assimilation of atlas or occipitalizationoccipitalizationThe failure of segmentation between the skull
and first cervical vertebra results in assimilation of the atlas
The assimilation may be complete or partial
It invariably results in basilar invagination Wackenheimclivusbaseline may be normal
but the clivus-canal angle may be decreased
1048708When incompletely assimilated the atlas arches appear too high on the lateral plain radiograph or when completely assimilated are not visible at all
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
TOPOGRAPHIC FORMS (WACKENHEIM) 1048708Type I Occipitalization(generally subtotal)
associated with BI 1048708Type II Occipitalization(generally subtotal)
associated with BI amp fusion of axis amp 3rdcervical vertebrae
1048708Type III Total or subtotal occipitalizationwith BI amp maldevelopmentof the transverse ligament
1048708Type III may be associated with various malformations like C2-C3 fusion hemivertebra dens aplasia tertiary condyle
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Anomalies of atlasAnomalies of atlas
With the exception of the various atlantooccipitalassimilations most atlas anomalies when isolated produce no abnormal CVJ relationships and are not associated with basilar invagination
The vast majority of anomalies consist of various arch clefts aplasias and hypoplasias
Arch anomalies are frequently mistaken for fractures in the evaluation of plain radiographs of patients with a history of cervical spine trauma
Differentiated from fracture Differentiated from fracture Developmental cleft margins are smooth with intact Developmental cleft margins are smooth with intact
cortical edge amp no soft tissue swelling cortical edge amp no soft tissue swelling Fracture Fracture jagged edges communicate with soft jagged edges communicate with soft
tissue welling displacement of lateral masses seen tissue welling displacement of lateral masses seen with axial compression fracturewith axial compression fracture
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Ponticulus Ponticulus posticuskimmerlersquos deformityposticuskimmerlersquos deformity
it is a bony ridge projecting posteriorlyfrom the articularedge of the atlas superior articularfacet
The bony projection may be only a few mm long or may elongate to unite with the adjacent neural arch of the atlas to produce an ldquoARCUATE CANALrdquothrough which the vertebral artery passes
This is due to ossification of a portion of the oblique A-O ligament
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Posterior arch anomalies(mc)Posterior arch anomalies(mc)
Total or partial aplasia of the posterior atlas arch is rare Although absence of the posterior arch when isolated is
usually asymptomatic but may be associated with anterior atlantoaxialsubluxation
Bilateral atlantoaxialsubluxationmay be associated with both total and partial aplasias simulating the Jefferson fracture
The majority of posterior atlas clefts (97) are midline whereas lateral clefts through the sulcusof the vertebral artery account for the remaining 3
Posterior arch rachischisismay be superimposed on the odontoidprocess or the axis body on the open-mouth odontoidview simulating a fracture
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Split atlasSplit atlas
It is typically encountered in association with posterior rachischisis-ldquosplit atlasrdquo
1048708Normally on a lateral radiograph the anterior arch of the atlas appears crescenticor half-moon-shaped with dense cortical bone surrounding the medullarycavity and a well-defined predentalspace
1048708In anterior arch rachischisis the anterior arch appears fat or plump and rounded in configuration appearing to lsquolsquooverlaprsquolsquothe odontoidprocess (making identification of the predentalspace impossible) the arch may have unsharp duplicated anterior margins
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Abnormalities of axisAbnormalities of axis
Stability dependent on integrity Stability dependent on integrity of osseous ligamentous and of osseous ligamentous and muscle complex Instability of muscle complex Instability of atlantoaxial joint is documented atlantoaxial joint is documented by lateral cervical radiographs in by lateral cervical radiographs in the fixed and extended neck the fixed and extended neck positionposition
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Group I Group I In combination with In combination with occipitalization of atlas frequent fusion of occipitalization of atlas frequent fusion of C2 amp C3 vertebrae Odontoid displaced C2 amp C3 vertebrae Odontoid displaced posteriorlyposteriorly
Group II Group II Incompetence of odontoid Incompetence of odontoid process due to its maldevelopment process due to its maldevelopment
Group III Group III No occipitalization and No occipitalization and odontoid normal Odontoid seen to be odontoid normal Odontoid seen to be merely dislocated backward and clearly merely dislocated backward and clearly seen in flexion seen in flexion
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Anomalies of axisAnomalies of axis
Atlanto-axial segementation Atlanto-axial segementation defectsdefects
Type I Os odontoideum Type II Ossiculum terminale Type III Agenesis of odontoid base Type IV Agenesis of apical segment Type V Agenesis of odontoid
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Os odontoideumOs odontoideum
an independent osseous structure lying cranial to the axis body in the place of dens
The anterior arch of the atlas is rounded and hypertrophic but the posterior arch is hypoplastic
As the gap between the os odondtum and the axis body usually extends above the level of the superior articular facet of the axis cruciate ligament incompetence and A-A instability are common
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Two types Two types Orthotopic Os lies in place of Orthotopic Os lies in place of
dens and moves in conjuction dens and moves in conjuction with atlas and axis (Transverse with atlas and axis (Transverse ligament is functional) ligament is functional)
Dystopic Os lies base or Dystopic Os lies base or occipital bone and moves with occipital bone and moves with the clivus with which it may the clivus with which it may fuse fuse
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Os odontoideumOs odontoideum Dens fractureDens fracture
Convex upper Convex upper margin of axis margin of axis bodybody
Flattened sharp Flattened sharp uncorticated upper uncorticated upper marginmargin
Hypertrophy of Hypertrophy of ant Arch of atlas ant Arch of atlas
Normal half moon Normal half moon shape shape Appearance of ant Appearance of ant Arch Arch
Convex post Convex post border and border and increased cortical increased cortical thickness thickness
Gap between Gap between fragments is fragments is characteristically characteristically narrow amp irregularnarrow amp irregular
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Persistent ossium terminalePersistent ossium terminale
(Bergmanrsquos ossicle)- failure of (Bergmanrsquos ossicle)- failure of fusion of terminal ossicle to the fusion of terminal ossicle to the remainder of odontoid process remainder of odontoid process (usually unites by 10-12 yrs ) (usually unites by 10-12 yrs ) Absolute differentiation with type Absolute differentiation with type 1 odontoid fracture may be 1 odontoid fracture may be difficult at times Whether difficult at times Whether congenital or traumatic in origin congenital or traumatic in origin this anomaly is stable when this anomaly is stable when isolatedisolated
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Odontoid aplasiaOdontoid aplasia
Total aplasiaof the odontoidprocess is extremely rare
A true aplasiais associated with an excavation defect into the body of axis
may simulate osodontoideum as the osfragment may be perfectly projected over the atlas arch on the open mouth odontoidview
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Traumatic lesions of cvjTraumatic lesions of cvj
MC clinical features are LOC or cranial nerve damage
Classification (Anderson amp Montesano) Type I impacted ndashdue to axial loading Type II Basilar skull -due to direct blow
to skull Type III Avulsion Type I amp II are stable injuries while type III
is potentially unstable
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare 1048708 Jefferson s burst of atlas 1stdescribed by
Geoffrey jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
OCCIPITO-ATLANTAL INSTABILITY Traumatic non traumatic Traumatic usually fatal 8 incidence in RTA Seen with cardiorespiratoryarrest quadriplegia loss
of autonomic function VA insufficiency etc
Traynelisclassification
Type I anterior displacement of occiputon atlas Type II vertical displacement bw occiputamp cervical
spine Type III posterior displacement of occiputon atlas
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
OF ATLAS Posterior arch 23rdof all occur at the junction of
posterior arch amp lateral mass (hyperextension injury) Anterior arch rare Jefferson s burst of atlas 1stdescribed by Geoffrey
jeffersonin 1920Jeffersonrsquos
Axial loading ndashdownward displacement of condyleswith separation of lateral mass of C1
Classically 4 part -2 each in ant amp post arch neck pain amp stiffness Cervical collar Halo immobilization
Non union ndashocciputto C2 fusion
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
HANGMANrsquoS ( TRAUMATIC SPONDYLOLISTHESIS OF AXIS )
ldquoJudicial Hangingrdquo-submentalknots causes dislocation of neural arch of axis
Today majority due to RTA Bl passing downward through the neural arch of
axis with resultant anterior displacement of C2 on C3
Two basic mechanisms
Hyperextension amp distraction Hyperextension amp compression
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Type I are either non-displaced or have no angulationamp lt3mm of displacement (stable injury with uncommon neurological deficits)
Type II with significant angulationamp translation of anterior fragment
Type III with severe angulationamp displacement along with concomitant UL or BL facet dislocation
Neck pain but neurological deficits less Surgical Rx seldom required due to high chances of
spontaneous interbodyfusion amp healing Most managed by reduction amp external
immobilization
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Hangmans x-rayHangmans x-ray
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Hangman ctHangman ct
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
ODONTOID Constitute about 7 ndash14 of cervical spine Flexion is the MC mechanism of injury causing
anterior displacement of C1 on C2
Anderson amp DrsquoAlonzoclassificationndash Type I oblique avulsion through the upper part of
the odontoidprocess at the point of alarligament attachment
Type II occur at the junction of the odontoidprocess amp the body of axis
Type III extend down in to the body of axis
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Type I are stable amp heal well if immobilisedin a collar or brace
Type III are usually stable skull traction fbhalo or brace for 3 ndash4 months results in fusion
Type II are prone to non union with a failure rate of 30 -60 with conservative measures
Indications for Sxndashdisplacement gt= 5mm nonunion age gt7 years disruption of the TL
Odontoidcompression screws (acute type II ) C1-2 arthrodesis(wiring fusion transarticularscrews
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Cvj anomalies in downs Cvj anomalies in downs syndromesyndrome
Characterized by increased ligamentouslaxity and abnormal joint and bony anatomy which predispose to instability
1048708Incidence of radiologicAA instability ranges from 7 to 40 although lt 1 of patients are symptomatic
1048708The incidence of bony anomalies involving the occipital condyle C1 ring and odontoidis also increased in Down syndrome
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Chiari malformationsChiari malformations
The Chiarimalformations are a group of hindbrain herniationsyndromes initially described by Austrian pathologist Hans Chiariin 1891
1048708Types of Chiari malformations Type I Caudal descent of cerebellartonsils in
cervical spine Osseous anomalies of posterior skull base and spine
It presents in early adulthood rather than at birth Associated with syringomyeliain 50 to 70
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Type II Caudal descent of cerebellarvermisand brain stem into cervical spine
Open spinal dysraphism Hydrocephalus Multiple neuroaxisanomalies
Type III Craniocervicalencephalocelecontaining portions of cerebellum and brain stem
Hydrocephalus Type IV (Controversial not commonly accepted as a
Chiarimalformation)
Aplasiahypoplasiacerebellum
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Non traumatic non developmental Non traumatic non developmental conditions associated with cvjconditions associated with cvj
Griselsyndrome Atlantoaxialsubluxationassociated with inflammation of adjacent soft tissues of the neck
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Rheumatoid arthritis From laxity of the ligaments and
destruction of the articularcartilage Osteogenesisimperfecta Neurofibromatosis Morquiosyndrome Secondary to odontoidhypoplasiaor aplasia Other arthridities(PsoriasisLupus
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Rheumatoid arthritisRheumatoid arthritis
AAD is due to loss of tensile strength amp stretching of TL due to destructive inflammatory changes as well as secondary degenerative changes in tissues from vasculitis
1048708Similar changes occur in the median amp lateral joints which result in erosive changes in adjacent bone amp formation of granulation tissue in the synovialjoints
1048708Odontoidprocess ndashosteoporosis angulation
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Osteophyteformation (stabilizing effect) does not occur secondary to deficient osteogenesis(characteristic of RA)
BI occurs secondary to loss of bone in lateral mass of the atlas with resultant rostralmigration of axis vertebra
The lateral mass of atlas may with lateral displacement of bone fragment
Later on erosion of occipital condylesoccur Excessive granulation tissue along with
invaginatedodontoidproduces ventral cervicomedullarycompression
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Tb Tb
lt1 of all cases of spinal TB 1048708Local pain restriction of neck movements amp acute
tenderness of upper C-spine ndashCardinal features 1048708Compression of CMJ could be due to granulation
tissue cold abscess or bony instability amp displacement
1048708Lower cranial Nerves paralysis + 1048708Waxing amp waning picture due to acute
compression of ASA on flexion which gets releivedon extension
1048708Ligaments are extensively infiltrated by the disease process amp give way
1048708Hyperaemicdecalcification occurs
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Radiological findings in 3 stagesndash
Stage I Retropharyngeal abscess with ligamentouslaxity + bony architecture of C1-C2 preserved
Stage II Ligamentousdisruption with AAD minimal bone destruction amp retropharyngeal mass +
Stage III marked destruction of bone complete obliteration of anterior arch of C1 amp complete loss of odontoidprocess marked AAD amp O-A instability
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
neoplasmsneoplasms
Unusual Metastaticmalignancies such as carcinoma of the
breast lung prostate kidney and thyroid in adults and neuroblastoma Ewingrsquos tumor leukemia hepatomaand retinoblastoma in children are most common
Primary malignancies involving the craniocervicaljunction are rare(multiplemyeloma)
Benign tumors are very rare
Thank youThank you
DrsameeraDrsameera
Thank youThank you
DrsameeraDrsameera
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