Transcript Skeletal System Gross Anatomy

Lecture 6
Skeletal System:Axial Skeleton
7-1
The Complete Skeleton
•Axial skeleton
–Skull
–Hyoid bone
–Vertebral column
–Thoracic (rib) cage
•Appendicular skeleton
–Limbs
–Girdles
Fig. 7.1
7-2
Superior and Posterior Views of
Skull or Cranium
Fig. 7.5
• External occipital protuberance
– Ligamentum nuchae: Helps keep head erect
• Nuchal lines: Neck muscle attachment
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Lateral View of Skull
Fig. 7.6
• Temporal lines (temporalis muscle)
• Mandible
– Condyle
– Coronoid process for temporalis muscle
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Frontal View of Skull
Frontal bone
Parietal bone
Temporal bone
Ethmoid bone
Lacrimal bone
Zygomatic bone
Maxilla
Sphenoid bone
Nasal bone
Perpendicular plate of
ethmoid bone
Vomer
Inferior nasal concha
Mandible
Fig. 7.4
• Optic foramen (optic nerve)
• Lacrimal groove (tears from eye to nasal capsule)
7-5
Inferior View of Skull
Hard palate
Maxilla
Palatine bone
Temporal process of
zygomatic bone
Zygomatic process of
temporal bone
Vomer
Sphenoid bone
Zygomatic
arch
Styloid process
Mandibular fossa
Temporal bone
Jugular foramen
Mastoid process
Occipital condyle
Carotid canal
Foramen magnum
Occipital bone
External occipital crest
Inferior nuchal line
Superior nuchal line
External occipital protuberance
Fig. 7.8
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•
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Foramen magnum
Occipital condyles
Jugular foramen, carotid canal
Hard palate - maxilla and palatine
Fig. 7.8
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Hyoid Bone and Auditory
Ossicles
• Hyoid bone
– Unpaired
– No direct bony attachment
to skull
– Attachment point for some
tongue muscles
– Attachment point for neck
muscles that elevate larynx
during speech and
swallowing
Fig. 7.26
• Auditory ossicles
– Malleus, incus and stapes
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Vertebra
• Parts
–
–
–
–
–
–
–
Body
Vertebral foramen
Vertebral arch
Superior and inferior articular processes
Transverse process
Articular facets for rib
Spinous process
Fig. 7.29
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Vertebral Column
• Regions
–
–
–
–
–
Fig. 7.28
Cervical (7 vertebrae)
Thoracic (12 vertebrae)
Lumbar (5 vertebrae)
Sacral bone (1)
Coccygeal bone (1)
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Cervical Vertebrae
• Atlas
– First vertebra
– ‘yes’ motion
• Axis
Fig. 7.30
– Second vertebra
– Dens or odontoid process
– ‘no’ motion
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Thoracic and Lumbar Vertebrae
Table 7.5
Table 7.5
7-11
Sacrum and Coccyx
Fig. 7.31
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Review Question
The spinal cord passes along the vertebral column through
the _______ and enters the skull through the
__________.
(a) Spinous process, mandibular fossa
(b) Body, occipital condyles
(c) Superior and inferior articular processes, jugular foramen
(d) Vertebral arch, carotid canal
(e) None of the above is correct
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Thoracic Cage and Sternum
• Parts
– Thoracic vertebrae
– Ribs (12 pair)
• True
• False
– Sternum (manubrium,
body)
Fig. 7.32
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Points to Remember
• Two major components of the human skeleton:
– Axial skeleton arranged along the medial axis
– Appendicular skeleton connects to the axial skeleton
• Skull consists of:
– 22 bones (single and paired)
– 6 auditory ossicles (3 each side) and 1 hyoid
• Vertebral column consists of:
–
–
–
–
–
Cervicals (7)
Thoracics (12)
Lumbars (5)
Sacrum (5, fused)
Coccyx (3-5, fused)
• Rib cage has true (bone) ribs and false (cartilage) ribs
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Questions?
7-16