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PowerPoint Lecture Slides prepared by Leslie Hendon University
of Alabama, Birmingham
C H A P T E R
Copyright 2011 Pearson Education, Inc.
Part 1
7 Bones, Part 1: The Axial Skeleton
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The Skeleton
Consists of: Bones, cartilage, joints, and ligaments
Composed of 206 named bones grouped into two divisions Axial
skeleton (80 bones) Appendicular skeleton (126 bones)
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The Axial Skeleton(in green)
Formed from 80 named bones
Consists of skull, vertebral column, and bony thorax
Figure 7.1a
Skull
Thoracic cage (ribs and sternum)
(a) Anterior view
Facial bones Cranium
Sacrum
Vertebral column
Clavicle Scapula Sternum Rib Humerus Vertebra Radius Ulna
Carpals
Phalanges Metacarpals Femur Patella Tibia Fibula
Tarsals Metatarsals Phalanges
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The Axial Skeleton
Figure 7.1b (b) Posterior view
Cranium
Clavicle Bones of pectoral girdle
Bones of pelvic girdle
Upper limb
Scapula
Rib Humerus Vertebra Radius Ulna
Carpals Phalanges Metacarpals Femur
Lower limb
Tibia Fibula
Copyright 2011 Pearson Education, Inc. Figure 7.6a
The Skull
Formed by cranial and facial bones
Parietal bone
Squamous part of frontal bone Nasal bone Sphenoid bone (greater
wing) Temporal bone Ethmoid bone Lacrimal bone Zygomatic bone
Maxilla
Mandible
Infraorbital foramen
Mental foramen
(a) Anterior view of skull
Mental protuberance
Frontal bone
Glabella
Frontonasal suture
Supraorbital foramen (notch) Supraorbital margin Superior
orbital fissure
Inferior orbital fissure
Middle nasal concha
Inferior nasal concha
Vomer
Optic canal
Perpendicular plate Ethmoid bone
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The Cranium
Is the bodys most complex bony structure Formed by cranial and
facial bones The cranium Encloses and protects brain Provides
attachment for head and neck
muscles
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The Face
Facial bones serve to Form framework of the face Form cavities
for the sense organs of sight,
taste, and smell Provide openings for the passage of air and
food Hold the teeth in place Anchor muscles of the face
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The Cranium Bones of cranium (cranial vault)
Lambdoid suture
Facial bones
Squamous suture
(a) Cranial and facial divisions of the skull
Coronal suture
Figure 7.2a
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Anterior cranial fossa
Middle cranial fossa
Posterior cranial fossa
(b) Superior view of the cranial fossae
Frontal lobe of cerebrum
Temporal lobe of cerebrum Cerebellum
Posterior Middle Anterior
Cranial fossae
(c) Lateral view of cranial fossae showing the contained brain
regions
Overview of Skull Geography
Facial bones form anterior aspect Cranium is divided into
cranial vault and the
base Internally, prominent bony ridges divide skull
into distinct fossae
Figure 7.2b, c Copyright 2011 Pearson Education, Inc.
Overview of Skull Geography
The skull contains smaller cavities Middle and inner ear
cavitiesin lateral
aspect of cranial base Nasal cavitylies in and posterior to
the
nose Orbitshouse the eyeballs Air-filled sinusesoccur in several
bones
around the nasal cavity
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Overview of Skull Geography
The skull contains approximately 85 named openings Foramina,
canals, and fissures Provide openings for important structures
Spinal cord Blood vessels serving the brain 12 pairs of cranial
nerves
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Cranial Bones
Formed from eight large bones Paired bones include Temporal
bones Parietal bones
Unpaired bones include Frontal bone Occipital bone Sphenoid bone
Ethmoid bone
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Parietal Bones and Sutures
Parietal bones form superior and lateral parts of skull
Four sutures of the cranium Coronal sutureruns in the coronal
plane Located where parietal bones meet the
frontal bone Squamous sutureoccurs where each
parietal bone meets a temporal bone inferiorly
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Parietal Bones and Sutures
Four sutures of the cranium (continued) Sagittal sutureoccurs
where right and left
parietal bones meet superiorly Lambdoid sutureoccurs where the
parietal
bones meet the occipital bone posteriorly
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Sutural Bones
Small bones that occur within sutures Irregular in shape, size,
and location Not all people have sutural bones
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Lambdoid suture Occipital bone
Superior nuchal line
External occipital protuberance
Sutural bone
Inferior nuchal line
Occipital condyle
External occipital crest Occipitomastoid suture
Parietal bone
Sagittal suture The Skull Posterior View
Figure 7.5
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Maxilla (palatine process)
Hard palate
Zygomatic bone
Incisive fossa
Median palatine suture Intermaxillary suture
Infraorbital foramen Maxilla Sphenoid bone (greater wing)
Foramen ovale Pterygoid process
Foramen lacerum Carotid canal External acoustic meatus
Stylomastoid foramen Jugular foramen
Foramen magnum
Occipital condyle Inferior nuchal line Superior nuchal line
Temporal bone (zygomatic process)
Mandibular fossa
Vomer
Styloid process
External occipital crest External occipital protuberance (a)
Inferior view of the skull (mandible removed)
Mastoid process Temporal bone (petrous part) Basilar part of the
occipital bone Occipital bone
Palatine bone (horizontal plate)
Foramen spinosum
Inferior Aspect of the Skull
Figure 7.7a Copyright 2011 Pearson Education, Inc.
(b) Photograph of right side of skull
Sphenoid bone (greater wing)
Coronal suture
Parietal bone Squamous suture
Zygomatic process
Temporal bone
Lambdoid suture Occipital bone
External occipital protuberance Occipitomastoid suture External
acoustic meatus Mastoid process Styloid
process Mandibular ramus Mandibular angle
Mental foramen
Frontal bone
Ethmoid bone Lacrimal bone Nasal bone Lacrimal fossa Zygomatic
bone
Maxilla
Mandible
Coronoid process
Alveolar margins
Mandibular condyle
Mandibular notch
Lateral Aspect of the Skull
Figure 7.4b
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The Temporal Bone
Figure 7.8
Mastoid region
External acoustic meatus
Mastoid process
Styloid process Tympanic region
Mandibular fossa
Zygomatic process
Squamous region
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(a) Superior view, as in Figure 7.9
Optic canal
Greater wing Sella turcica
Lesser wing
Foramen rotundum Foramen ovale Foramen spinosum
Body of sphenoid
The Sphenoid Bone
Figure 7.10a
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Greater wing
Body of sphenoid
Superior orbital fissure
Lesser wing
Pterygoid process
(b) Posterior view
The Sphenoid Bone
Figure 7.10b Copyright 2011 Pearson Education, Inc.
Orbital plate
Ethmoidal air cells
Perpendicular plate
Middle nasal concha
Cribriform plate Olfactory foramina
Crista galli
Left lateral mass
Figure 7.12
The Ethmoid Bone
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Facial Bones
Unpaired bones Mandible and vomer
Paired bones Maxillae Zygomatic bones Nasal bones Lacrimal bones
Palatine bones Inferior nasal conchae
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Parietal bone
Squamous part of frontal bone Nasal bone Sphenoid bone (greater
wing) Temporal bone Ethmoid bone Lacrimal bone Zygomatic bone
Maxilla
Mandible
Infraorbital foramen
Mental foramen
(a) Anterior view of skull
Mental protuberance
Frontal bone Glabella Frontonasal suture Supraorbital foramen
(notch) Supraorbital margin Superior orbital fissure
Inferior orbital fissure
Middle nasal concha
Inferior nasal concha Vomer
Optic canal
Perpendicular plate Ethmoid bone
Facial Bones
Figure 7.6a
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Coronoid process
Mandibular foramen
Mental foramen
Mandibular angle
Ramus of mandible
Mandibular condyle
Mandibular notch
Mandibular fossa of temporal bone
Body of mandible
Alveolar margin
(a) Mandible, right lateral view
Temporomandibular joint
Mandible
Figure 7.13a Copyright 2011 Pearson Education, Inc.
Maxillary Bones
Figure 7.13b
Frontal process
Articulates with frontal bone
Anterior nasal spine
Infraorbital foramen
Alveolar margin
(b) Maxilla, right lateral view
Orbital surface
Zygomatic process (cut)
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Maxilla (palatine process)
Hard palate
Zygomatic bone
Incisive fossa
Median palatine suture Intermaxillary suture
Infraorbital foramen Maxilla Sphenoid bone (greater wing)
Foramen ovale Pterygoid process
Foramen lacerum Carotid canal External acoustic meatus
Stylomastoid foramen Jugular foramen
Foramen magnum
Occipital condyle Inferior nuchal line Superior nuchal line
Temporal bone (zygomatic process)
Mandibular fossa
Vomer
Styloid process
External occipital crest External occipital protuberance (a)
Inferior view of the skull (mandible removed)
Mastoid process Temporal bone (petrous part) Basilar part of the
occipital bone Occipital bone
Palatine bone (horizontal plate)
Foramen spinosum
Maxillary Bones
Figure 7.7a Copyright 2011 Pearson Education, Inc.
Other Bones of the Face
Zygomatic bones Form lateral wall of orbits
Nasal bones Form bridge of nose
Lacrimal bones Located in the medial orbital walls
Palatine bones Complete the posterior part of the hard
palate
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Other Bones of the Face
Vomer Forms the inferior part of the nasal septum
Inferior nasal conchae Thin, curved bones that project medially
form
the lateral walls of the nasal cavity
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Special Parts of the Skull
Orbits Nasal cavity Paranasal sinuses Hyoid bone
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Nasal Cavity
Figure 7.14a
Frontal sinus Superior nasal concha Middle nasal concha
Ethmoid bone
Inferior nasal concha Nasal bone
Maxillary bone (palatine process)
Palatine bone (perpendicular plate)
Palatine bone (horizontal plate)
Pterygoid process
(a) Bones forming the left lateral wall of the nasal cavity
(nasal septum removed)
Sphenoid sinus
Sphenoid bone
Superior, middle, and inferior meatus
Anterior nasal spine
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Vomer
Crista galli Cribriform plate
Ethmoid bone Frontal sinus
Nasal bone
Septal cartilage
Alveolar margin of maxilla
Perpendicular plate of ethmoid bone
Sella turcica
Sphenoid sinus
Palatine bone
Palatine process of maxilla
(b) Nasal cavity with septum in place showing the contributions
of the ethmoid bone, the vomer, and septal cartilage
Hard palate
Nasal Septum
Figure 7.14b
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Paranasal Sinuses
Air-filled sinuses are located within Frontal bone Ethmoid bone
Sphenoid bone Maxillary bones
Lined with mucous membrane Lighten the skull
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Paranasal Sinuses
Figure 7.15a, b
Frontal sinus Ethmoidal air cells (sinus)
Maxillary sinus
Sphenoid sinus
(a) Anterior aspect
Frontal sinus Ethmoidal air cells
Maxillary sinus
Sphenoid sinus
(b) Medial aspect
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Orbits
Figure 7.16b
Roof of orbit
Medial wall
Orbital plate of ethmoid bone
Sphenoid body
Supraorbital notch Optic canal
Floor of orbit Orbital process of palatine bone Orbital surface
of maxillary bone
Lacrimal bone Nasal bone
Frontal process of maxilla
Lateral wall of orbit Zygomatic process of frontal bone Greater
wing of sphenoid bone Orbital surface of zygomatic bone
Zygomatic bone
Zygomatic bone
Inferior orbital fissure Infraorbital groove
Infraorbital foramen
Superior orbital fissure
(b) Contribution of each of the seven bones forming the right
orbit
Lesser wing of sphenoid bone Orbital plate of frontal bone
Copyright 2011 Pearson Education, Inc. Figure 7.17
The Hyoid Bone
Lies inferior to the mandible
The only bone with no direct articulation with any other
bone
Acts as a movable base for the tongue
Greater horn
Lesser horn
Body
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The Vertebral Column
Formed from 26 bones in the adult Transmits weight of trunk to
the lower limbs Surrounds and protects the spinal cord
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The Vertebral Column
Serves as attachment sites for muscles of the neck and back
Held in place by ligaments Anterior and posterior longitudinal
ligaments Ligamentum flavum
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The Vertebral Column
Figure 7.18
Cervical curvature (concave)
7 vertebrae, C1 C7
Thoracic curvature
(convex) 12 vertebrae,
T1 T12
Lumbar curvature (concave)
5 vertebrae, L1 L5
Sacral curvature
(convex) 5 fused vertebrae sacrum
Coccyx 4 fused vertebrae Anterior view Right lateral view
C1
T 1 2 3 4 5 6 7 8 9
10 11 12
L 1 2 3 4 5
2 3 4 5 6 7
Spinous process Transverse processes
Intervertebral discs Intervertebral foramen
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Regions and Normal Curvatures
The Vertebral column has five major regions 7 cervical vertebrae
of the neck region 12 thoracic vertebrae 5 lumbar vertebrae
Sacrumfive fused bones Inferior to lumbar vertebrae
Coccyxinferior to sacrum
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Regions and Normal Curvatures
Curvatures of the spine Cervical and lumbar curvatures Concave
posteriorly
Thoracic and sacral curvatures Convex posteriority
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Regions and Normal Curvatures
Curvatures increase resilience of spine Thoracic and sacral
curvatures Primary curvatures Present at birth
Lumbar curvature Develops when baby begins to walk
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Ligaments of the Spine
Major supporting ligaments Anterior longitudinal ligament
Attaches to bony vertebrae and
intervertebral discs Prevents hyperextension
Posterior longitudinal ligament Narrow and relatively weak
Attaches to intervertebral discs
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Posterior longitudinal ligament
Anterior longitudinal ligament
Body of a vertebra
Intervertebral disc
(b) Anterior view of part of the spinal column
Ligaments of the Spine
Supraspinous ligament Intervertebral disc Anterior longitudinal
ligament
Intervertebral foramen Posterior longitudinal ligament
Anulus fibrosus
Nucleus pulposus
Sectioned body of vertebra
Transverse process
Sectioned spinous process
Ligamentum flavum
Interspinous ligament
Inferior articular process
(a) Median section of three vertebrae, illustrating the
composition of the discs and the ligaments
Figure 7.19a, b
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Ligaments of the Spine
Figure 7.19c, d
Vertebral spinous process (posterior aspect of vertebra)
Spinal nerve root
Anulus fibrosus of disc
Herniated portion of disc
Nucleus pulposus of disc
Spinal cord
(c) Superior view of a herniated intervertebral disc
Transverse process
(d) MRI of lumbar region of vertebral column in sagittal section
showing normal and herniated discs
Nucleus pulposus of intact disc
Herniated nucleus pulposus
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Intervertebral Discs
Are cushion-like pads between vertebrae Composed of Nucleus
pulposus Anulus fibrosus
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Intervertebral Discs
Nucleus pulposus Gelatinous inner sphere Absorbs compressive
stresses
Anulus fibrosus Outer fings formed of ligament Inner rings
formed of fibrocartilage Contain the nucleus pulposus
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General Structure of Vertebrae
PLAY Spine (horizontal)
Figure 7.20
Posterior
Anterior
Lamina
Superior articular process and facet
Transverse process
Pedicle
Spinous process
Vertebral arch
Vertebral foramen
Body (centrum)
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General Structure of Vertebrae
Common structures to all regions Body Vertebral arch Vertebral
foramen Spinous process Transverse process Superior and inferior
articular processes Intervertebral foramina
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Regions Vertebral Characteristics
Specific regions of the spine perform specific functions
Types of movement that occur between vertebrae Flexion and
extension Lateral flexion Rotation in the long axis
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Cervical Vertebrae
Seven cervical vertebrae (C1C7)smallest and lightest
vertebrae
C3C7 are typical cervical vertebrae Body is wider laterally
Spinous processes are short and bifid (except
C7) Vertebral foramen are large and triangular Transverse
processes contain transverse
foramina Superior articular facets face
superoposteriorly
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Cervical Vertebrae
Table 7.2a
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Dens of axis Transverse ligament of atlas C1 (atlas) C2
(axis)
C3
Bifid spinous process Transverse processes
C7 (vertebra prominens)
(a) Cervical vertebrae
Inferior articular process
Cervical Vertebrae
Figure 7.22a Copyright 2011 Pearson Education, Inc.
The Atlas
C1 is termed the atlas Lacks a body and spinous process Supports
the skull Superior articular facets receive the occipital
condyles Allows flexion and extension of neck Nodding the head
yes
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The Atlas
Figure 7.21a
Anterior arch
Superior articular facet
Transverse foramen
Posterior arch
Posterior tubercle
Anterior tubercle
Posterior
Lateral masses
(a) Superior view of atlas (C1)
C1
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The Atlas
Figure 7.21b
Facet for dens
Transverse process Lateral
masses
Transverse foramen
Posterior arch
Posterior tubercle Posterior
Anterior tubercle
Anterior arch
(b) Inferior view of atlas (C1)
Inferior articular facet
C1
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The Axis
Has a body and spinous process Dens (odontoid process) projects
superiorly Formed from fusion of the body of the atlas
with the axis Acts as a pivot for rotation of the atlas and
skull Participates in rotating the head from side to
side
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The Axis
Figure 7.21c
C2 Posterior
Dens
(c) Superior view of axis (C2)
Inferior articular process
Body
Superior articular facet Transverse process
Pedicle
Lamina Spinous process
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Thoracic Vertebrae (T1T12)
All articulate with ribs Have heart-shaped bodies from the
superior
view Each side of the body of T1T10 bears
demifacts for articulation with ribs T1 has a full facet for the
first rib T10T12 only have a single facet
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Thoracic Vertebrae
Table 7.2b
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Thoracic Vertebrae
Spinous processes are long and point inferiorly
Vertebral foramen are circular Transverse processes articulate
with
tubercles of ribs Superior articular facets point posteriorly
Inferior articular processes point anteriorly Allows rotation and
prevents flexion and
extension
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Lumbar Vertebrae (L1L5)
Bodies are thick and robust Transverse processes are thin and
tapered Spinous processes are thick, blunt, and point
posteriorly Vertebral foramina are triangular Superior and
inferior articular facets directly
medially Allows flexion and extensionrotation
prevented
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Lumbar Vertebrae
Table 7.2c Copyright 2011 Pearson Education, Inc.
Superior articular process
Transverse process
Spinous process
Intervertebral disc
Body
Inferior articular process
(c) Lumbar vertebrae
Lumbar Vertebrae
Figure 7.22c
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Sacrum (S1S5)
Shapes the posterior wall of pelvis Formed from 5 fused
vertebrae Superior surface articulates with L5 Inferiorly
articulates with coccyx Sacral promontory Where the first sacral
vertebrae bulges into
pelvic cavity Center of gravity is 1 cm posterior to sacral
promontory Aladevelops from fused rib elements
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Sacrum
Sacral foramina Ventral foramina Passage for ventral rami of
sacral spinal
nerves Dorsal foramina Passage for dorsal rami of sacral
spinal
nerves
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Sacrum
Figure 7.23
Body of first sacral vertebra
Transverse ridges (sites of vertebral fusion)
Coccyx Coccyx
Anterior sacral foramina Apex
Posterior sacral foramina
Median sacral crest
Sacral promontory Sacral canal
Sacral hiatus
Body Facet of superior articular process
Lateral sacral crest
Auricular surface
Ala
(a) Anterior view (b) Posterior view
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Coccyx
Is the tailbone Formed from 35 fused vertebrae Offers only
slight support to pelvic organs
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The Thoracic Cage
Forms the framework of the chest Components Thoracic
vertebraeposteriorly Ribslaterally Sternum and costal
cartilageanteriorly
Protects thoracic organs Supports shoulder girdle and upper
limbs Provides attachment sites for muscles
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Intercostal spaces
True ribs (17
False ribs (812)
Jugular notch Clavicular notch
Manubrium Sternal angle Body Xiphisternal joint Xiphoid
process
L1 Vertebra
Floating ribs (11, 12) (a) Skeleton of the thoracic cage,
anterior view
Sternum
Costal cartilage Costal margin
The Thoracic Cage
Figure 7.24a
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The Thoracic Cage
Figure 7.24b
Xiphisternal Xiphisternal joint
Heart
Sternal angle
Jugular notch
(b) Midsagittal section through the thorax, showing the
relationship of surface anatomical landmarks of the thorax to the
vertebral column
T2
T4
T3
T9
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Sternum
Formed from three sections Manubriumsuperior section Articulates
with medial end of clavicles
Bodybulk of sternum Sides are notched at articulations for
costal
cartilage of ribs 27 Xiphoid processinferior end of sternum
Ossifies around age 40
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Sternum
Anatomical landmarks Jugular notch Central indentation at
superior border of the
manubrium Sternal angle A horizontal ridge where the
manubrium
joins the body Xiphisternal joint Where sternal body and xiphoid
process
fuse Lies at the level of the 9th thoracic vertebra
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Ribs
All ribs attach to vertebral column posteriorly True ribs -
superior seven pairs of ribs Attach to sternum by costal
cartilage
False ribsinferior five pairs of ribs Ribs 1112 are known as
floating ribs
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Ribs
Figure 7.25a, b
Junction with costal cartilage
Shaft Head Neck Articular facet on tubercle
Costal angle Costal groove
Facets for articulation with vertebrae
(a) A typical rib (rib 6, right), posterior view
Transverse costal facet (for tubercle of rib) Superior costal
facet
(for head of rib) Body of vertebra Head of rib
Intervertebral disc
Tubercle of rib Neck of rib
Shaft Sternum
Angle of rib
Cross- section of rib Costal groove
(b) Vertebral and sternal articulations of a typical true rib
Costal cartilage
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Spinous process Articular facet on tubercle of rib
Shaft
Ligaments
Neck of rib
Head of rib Body of thoracic vertebra
Transverse costal facet (for tubercle of rib)
Superior costal facet (for head of rib)
(c) Superior view of the articulation between a rib and a
thoracic vertebra
Ribs
Figure 7.25c
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Disorders of the Axial Skeleton
Cleft palate A common congenital disorder Right and left halves
of palate fail to fuse
medially Stenosis of the lumbar spine Narrowing of the vertebral
canal Can compress roots of spinal nerves
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Disorders of the Axial Skeleton
Abnormal spinal curvatures Scoliosisan abnormal lateral
curvature Kyphosisan exaggerated thoracic
curvature Lordosisan accentuated lumbar curvature;
swayback
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The Axial Skeleton Throughout Life
Membrane bones begin to ossify in second month of
development
Bone tissue grows outward from ossification centers
Fontanels Unossified remnants of membranes
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Fontanelles
Figure 7.28a
Occipital bone
Parietal bone
Anterior fontanelle
Frontal suture Frontal bone
Ossification center
(a) Superior view
Posterior fontanelle
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Fontanelles
Figure 7.28b
Frontal bone
Sphenoidal fontanelle
(b) Lateral view
Posterior fontanelle
Mastoid fontanelle
Parietal bone
Ossification center
Occipital bone
Temporal bone (squamous portion)
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The Axial Skeleton Throughout Life
Many bones of the face and skull form by intramembranous
ossification
Endochondral bones of the skull Occipital bone Sphenoid Ethmoid
bones Parts of the temporal bone
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The Axial Skeleton Throughout Life
Aging of the axial skeleton Water content of the intervertebral
discs
decreases By age 55, loss of a few centimeters in height
is common Thorax becomes more rigid Bones lose mass with age
