3% of MVA patients , have cervical spine injury3% of MVA patients , have cervical spine injury 10-20% patients with head injury, have also 10-20% patients with head injury, have also

cervical spine injurycervical spine injury Most cervical spine fractures occur at two Most cervical spine fractures occur at two

levelslevels 17% of patients have a missed or delayed 17% of patients have a missed or delayed

diagnosis with a risk of perminant neurologic diagnosis with a risk of perminant neurologic damagedamage

1/3 of injuries occur at level of C2 and ½ occur 1/3 of injuries occur at level of C2 and ½ occur at level of C6-C7at level of C6-C7

The NEXUS criteria state that a patient with The NEXUS criteria state that a patient with suspected cervical spine injury can be suspected cervical spine injury can be cleared providing the following:cleared providing the following:

*- no posterior midline cervical spine tenderness*- no posterior midline cervical spine tenderness

*- no evidence of intoxication is present*- no evidence of intoxication is present

*- patient has a normal level of alertness*- patient has a normal level of alertness

*- no focal neurologic deficit*- no focal neurologic deficit

Plain filmsPlain films

3 views should be taken3 views should be taken : :

- - true lateral viewtrue lateral view

( must include all 7 cervical ( must include all 7 cervical vertebrae as well as the C 7 – T1 junction )vertebrae as well as the C 7 – T1 junction )

- an AP view- an AP view

- an open mouth (odontoid view)- an open mouth (odontoid view)

The lateral view …The lateral view …

The lateral view is the most useful view, The lateral view is the most useful view, approximately 85-90 % of spinal injuries are approximately 85-90 % of spinal injuries are evident on this viewevident on this view

Should be obtained & examed before any other Should be obtained & examed before any other films are takenfilms are taken

All 7 cervical vertebrae and the C7-T1 junction All 7 cervical vertebrae and the C7-T1 junction must be visualized because the cervicothoracic must be visualized because the cervicothoracic junction is a common place for traumatic injuryjunction is a common place for traumatic injury

Is this an adequate Is this an adequate lateral film?lateral film?

AP & odontoid viewAP & odontoid view

If lateral view is normal, proceed with AP & If lateral view is normal, proceed with AP & odontoid viewsodontoid views

Patient should be maintained in cervical Patient should be maintained in cervical immobilization and plain films or CT scans immobilization and plain films or CT scans obtained untill all vertebrae are clearly obtained untill all vertebrae are clearly visible.visible.

AnatomyAnatomy

Lateral viewLateral view

AP viewAP view

Odontoid viewOdontoid view

AlignmentAlignment

Systematic Systematic approach:approach:

* check alignment by * check alignment by following 3 contour following 3 contour lineslines

- anterior contour line- anterior contour line

- - posterior contour lineposterior contour line

- - spinolaminar contour spinolaminar contour lineline

These lines should follow a slightly lordotic These lines should follow a slightly lordotic curve, smooth and without step-offs.curve, smooth and without step-offs.

Any malalignment should be considered Any malalignment should be considered evidence of ligamentous injury or occult evidence of ligamentous injury or occult fracture and cervical spine immobilization fracture and cervical spine immobilization should be maintained untill a definitive should be maintained untill a definitive diagnosis is made.diagnosis is made.

AP viewAP view Alignment should be Alignment should be evaluated using the edges evaluated using the edges of vertebral bodies and of vertebral bodies and articular pillarsarticular pillars

Hight of vertebral bodies Hight of vertebral bodies should be equalshould be equal

Hight of joint space should Hight of joint space should be equalbe equal

Spinous process should be Spinous process should be in midline, if displaced to in midline, if displaced to one side , a facet one side , a facet dislocation should be dislocation should be suspected.suspected.

Odontoid Odontoid viewview The distance from the The distance from the

dens to lateral dens to lateral masses of C1 should masses of C1 should be equal bilaterally.be equal bilaterally.

Any asymmetry is Any asymmetry is suggestive of a suggestive of a fracture of C1 or C2fracture of C1 or C2

Lateral mass of C1 Lateral mass of C1 should line up with should line up with lateral margins of lateral margins of suprior articular facet suprior articular facet of C2. if not, a of C2. if not, a fracture of C1 is fracture of C1 is suspected.suspected.

Prevertebral spacePrevertebral space

Nasopharyngeal space {C1} Nasopharyngeal space {C1}

-- 10 mm in adult-- 10 mm in adult

Retropharyngeal space {C2-C4}Retropharyngeal space {C2-C4}

-- 5-7 mm-- 5-7 mm

Retrotracheal space {C5-C7}Retrotracheal space {C5-C7}

-- 14mm in children-- 14mm in children

-- 22 mm in adults-- 22 mm in adults

Prevertebral soft tissue swelling is Prevertebral soft tissue swelling is important as it is usually due to hematoma important as it is usually due to hematoma 2ry to occult fractures2ry to occult fractures

Soft tissue swelling in symptomatic patient Soft tissue swelling in symptomatic patient should be considered an indication for should be considered an indication for further radiographic evaluationfurther radiographic evaluation

CTCT

CTCT 20% of fractures are missed on plain 20% of fractures are missed on plain

radiographsradiographs

Useful in fractures that result in Useful in fractures that result in neurologic deficit and in fractures of neurologic deficit and in fractures of posterior elements ( e.g. Jefferson’s posterior elements ( e.g. Jefferson’s fracture)fracture)

Advantages of CTAdvantages of CT

Excellent in identifying osseous Excellent in identifying osseous compromise of the vertebral canalcompromise of the vertebral canal

Visualization of subtle fractures Visualization of subtle fractures Provides patient comfort by being able to Provides patient comfort by being able to

reconstruct images in axial , sagittal , reconstruct images in axial , sagittal , coronal planes and 3D from one patient coronal planes and 3D from one patient position.position.

Soft tissue window & bone windowSoft tissue window & bone window

****** limitations:****** limitations:

* unable to show ligamentous * unable to show ligamentous

injuriesinjuries

* relatively high costs* relatively high costs

Excellent in Excellent in identifying identifying osseous osseous compromise of compromise of the vertebral the vertebral canalcanal

Visualization of subtle Visualization of subtle fractures fractures

Provides patient Provides patient comfort by being comfort by being able to reconstruct able to reconstruct images in axial , images in axial , sagittal and sagittal and coronal planes coronal planes from one patient from one patient position as well as position as well as 3-d reconstruction3-d reconstruction

Soft tissue Soft tissue window & window & bone bone windowwindow

MRI MRI

MRIMRI

Advantages:Advantages: * excellent soft tissue contrast, making it the * excellent soft tissue contrast, making it the

study of choice for spinal cord survey , study of choice for spinal cord survey , hematoma and ligamentous injuries.hematoma and ligamentous injuries.

* good general overview because of its ability to * good general overview because of its ability to show informations in different planesshow informations in different planes

* ability to demonstrate vertebral arteries which is * ability to demonstrate vertebral arteries which is useful in evaluating fractures involving the useful in evaluating fractures involving the course of vertebral arteriescourse of vertebral arteries

* no ionizing radiation* no ionizing radiation

MRIMRI

DisadvantagesDisadvantages

* loss of bony details* loss of bony details

* high cost* high cost

- patients with pacemakers and certain - patients with pacemakers and certain ferromagnetic materials ( aneurysm clips ) ferromagnetic materials ( aneurysm clips ) are not able to be scannedare not able to be scanned

MRI diagnostic values

Spinal cord lesions

Bone marrow pathology

Ligamentous injuries

soft tissue edema

MRIMRI

T1W – display anatomic details T1W – display anatomic details

T2W – display pathologic changes betterT2W – display pathologic changes better

Together – enable detection & Together – enable detection & characterization of most lesionscharacterization of most lesions

StabilityStability

Spinal stability is Spinal stability is depending on at depending on at least two intact least two intact columns.columns.

When two of the When two of the three columns are three columns are disrupted , it will disrupted , it will allow abnormal allow abnormal segmental motion.segmental motion.

Spinal cord injurySpinal cord injury Two types:Two types:

* non-hemorrhagic* non-hemorrhagic:: only high signal on only high signal on T2WT2W

* hemorrhagic:* hemorrhagic: areas of low areas of low

signals on T2W signals on T2W within the area of within the area of edemaedema

Hemorrhagic spinal cord injury has an extremely Hemorrhagic spinal cord injury has an extremely poor outcomepoor outcome

Mechanism of Mechanism of injuryinjury

HyperflexionHyperflexion

HyperextensionHyperextension

CompressionCompression

HyperflexionHyperflexion ……. …….

Excessive flexion of Excessive flexion of neck in sagittal planeneck in sagittal plane

Diving in shallow Diving in shallow waterwater

Flexion tear drop Flexion tear drop fracturefracture

HyperextensionHyperextension

Excessive Excessive extension of neck extension of neck in sagittal planein sagittal plane

Hitting the dash Hitting the dash board in MVAboard in MVA

Hangman’s Hangman’s fracturefracture

Axial compressionAxial compression

Force applied directly Force applied directly over the vertex in the over the vertex in the caudal directioncaudal direction

Jefferson fractureJefferson fracture Bursting fractureBursting fracture

Cervical spine injuriesCervical spine injuries

Unstable fracturesUnstable fractures Hyperflexion :Hyperflexion : - bilateral facet dislocation- bilateral facet dislocation - flexion tear drop fracture- flexion tear drop fracture

• HyperextensionHyperextension - Hangman’s fracture- Hangman’s fracture - hyperextension dislocation fracture- hyperextension dislocation fracture

• Compression :Compression : - Jefferson’s fracture- Jefferson’s fracture

• Complex :Complex : - odontoid fracture- odontoid fracture - atlanto-axial dissociation - atlanto-axial dissociation

Hyperflexion Hyperflexion unstable injuriesunstable injuries

•Bilateral facet dislocationBilateral facet dislocation•Flexion tear drop fracture .Flexion tear drop fracture .

Normal relationship of Normal relationship of facet joints, inferior facet joints, inferior articulating facet of articulating facet of body above (blue body above (blue arrow) lies posterior arrow) lies posterior to superior facet of to superior facet of body below (red body below (red arrow).arrow).

Body of C4 is Body of C4 is subluxed anteriorly on subluxed anteriorly on C5. inferior facet of C5. inferior facet of C4 (blur arrow) lies C4 (blur arrow) lies anterior to superior anterior to superior facet of C5 (red facet of C5 (red arrow).arrow).

Unilateral facet Unilateral facet dislocationdislocation

Due to Due to simultaneous simultaneous hyperflexion with hyperflexion with rotationrotation

30% associated 30% associated with neurologic with neurologic defectdefect

Radiographic features:Radiographic features: Lateral view :Lateral view :

- anterior dislocation - anterior dislocation of affected vertebral of affected vertebral body by less than ½ body by less than ½ of the vertebral AP of the vertebral AP diameter.diameter.

- widening of - widening of interspinous spaceinterspinous space

the superior facet on one side slides over the the superior facet on one side slides over the inferior facet and become locked, the inferior facet and become locked, the contralateral facet joint is only distracted. contralateral facet joint is only distracted.

AP view:AP view:

- malalignment of - malalignment of spinous processes spinous processes which can only be which can only be produced by a produced by a rotatory injury.rotatory injury.

the involved spinous the involved spinous processes points to processes points to the involved sidethe involved side

- due to the rotation, - due to the rotation, the involved spinous the involved spinous processes seem processes seem shorter on the lateral shorter on the lateral view view

** ** MRI MRI findingsfindings : :

Spinal cord lesionsSpinal cord lesions Soft tissue swellingSoft tissue swelling Rupture of Rupture of

interspinous ligament interspinous ligament and ligamentum and ligamentum flavumflavum

Rupture of the discRupture of the disc

Unilateral facet dislocation

Flexion and rotation forceFlexion and rotation force Limited antrolithesis less than 25%Limited antrolithesis less than 25%

Bilateral facet Bilateral facet dislocationdislocation

Results from Results from extreme extreme hyperflexionhyperflexion

UnstableUnstable Associated with a Associated with a

very high risk of very high risk of cord damagecord damage

******Radiographic Radiographic features:features:

Complete anterior Complete anterior dislocation of affected dislocation of affected vertebral body by half vertebral body by half or more of its AP or more of its AP diameterdiameter

Disruption of posterior Disruption of posterior ligament complex and ligament complex and anterior longitudinal anterior longitudinal ligamentligament

“ “ Bow-tie “ appearance Bow-tie “ appearance of the locked facetsof the locked facets

Essentials for diagnosis

• Displacement of the upper vertebra by more than 50% of the vertebra below

• The articular facets of the upper vertebra becomes anterior to articular facets of the

lower vertebra

•Common association

•Disc herniation

•Epidural hematoma

C4/5

5

4

Bilateral facet Bilateral facet dislocationdislocation

Hamburger signHamburger sign

UFDUFD BFDBFD

Flexion tear drop Flexion tear drop fracturefracture

MechanismMechanism : : hyperflexion with hyperflexion with compression compression

( diving into ( diving into shallow water )shallow water )

UnstableUnstable 70 % have 70 % have

neurologic deficitneurologic deficit

Radiographic Radiographic featuresfeatures

Posterior vertebral body Posterior vertebral body subluxation into the spinal subluxation into the spinal canalcanal

Teardrop fragment from Teardrop fragment from the anteroinferior aspect the anteroinferior aspect of the vertebral bodyof the vertebral body

Anterior longitudinal Anterior longitudinal ligament tear with ligament tear with prevertebral swelling prevertebral swelling

Spinal cord compression Spinal cord compression from vertebral body from vertebral body displacementdisplacement

Flexion teardrop fractureFlexion teardrop fracture

Hyperextension Hyperextension injuriesinjuries

Hangman’s fractureHangman’s fracture

Hangman’s fractureHangman’s fracture

Traumatic spondylolithesisTraumatic spondylolithesis Mechanism : hanging , chin hits dashboard in Mechanism : hanging , chin hits dashboard in

MVAMVA UnstableUnstable Seldom is associated with spinal Seldom is associated with spinal cord injury , since the AP diameter cord injury , since the AP diameter of the spinal canal is greatest at this of the spinal canal is greatest at this level and the fractured pedicles allow level and the fractured pedicles allow decompression decompression

Radiographic Radiographic features:features:

Prevertebral soft tissue swellingPrevertebral soft tissue swelling Avulsion of anterior inferior Avulsion of anterior inferior

corner of C2 associated with corner of C2 associated with rupture of anterior longitudinal rupture of anterior longitudinal ligamentligament

Anterior dislocation of C2 bodyAnterior dislocation of C2 body Bilateral C2 pars interarticularis Bilateral C2 pars interarticularis

fracturefracture

Hyperextension and Hyperextension and distractiondistraction

Fracture involves both Fracture involves both pars interarticularis of pars interarticularis of C2C2

Compression Compression fracturesfractures

Jefferson’s fractureJefferson’s fracture

Jefferson fractureJefferson fracture Description : compression Description : compression

fracture of C1fracture of C1 Mechanism : diving injuryMechanism : diving injury Stability : unstableStability : unstable Radiographic features : Radiographic features : - AP open mouth : lateral - AP open mouth : lateral

offset of lateral masses of offset of lateral masses of C1 beyond margins of C1 beyond margins of body of C2 body of C2

- CT is required to define - CT is required to define the extent of fracture and the extent of fracture and to detect fragments in to detect fragments in spinal canalspinal canal

Jefferson’s Jefferson’s fracture……………………...fracture……………………...

Complex Complex fracturesfracturesOdontoid fractureOdontoid fracture

Atlanto-occipital Atlanto-occipital dissociationdissociation

Odontoid fractureOdontoid fracture

Atlanto-occipital Atlanto-occipital disassociationdisassociation

Description: disruption of atlanto-occipital Description: disruption of atlanto-occipital junction involving atlanto-occipital junction involving atlanto-occipital articulationarticulation

Mechanism : hyperflexion or Mechanism : hyperflexion or hyperextensionhyperextension

Stability: unstableStability: unstable

Radiographic Radiographic features:features:

- Malposition of Malposition of occipital occipital condyles in condyles in relation to relation to superior facets superior facets of atalsof atals

- Prevertebral Prevertebral soft tissue soft tissue swellingswelling

Displacement of Displacement of atlanto –atlanto –occipital occipital articulationarticulation

Prevertebral Prevertebral soft tissue soft tissue swellingswelling