Axial Skeleton
Vertebral Column/ Spine
supports the skull /transfers weight
• Structure:
• 26 irregular bones
• (33 pre-birth)
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7 cervical
12 thoracic
5 lumbar
1 sacrum
1coccyx
• Intervertebral foramenBetween each vertebrae
For spinal nerves
Intervertebral discsCushion/absorbs shock
Provides flexibility
Hardens with age
Herniated Disc
• When the
annulus wall
weakens, the
disc will press
against the
spinal nerve =
PAIN
curvatures
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Primary curvatureWhat you are born with
Posterior = Convex
Secondary curvatureWhat develops
Cervical becomesposterior concave when
baby lifts head
• Lumbar becomes posterior
concave when baby walks
Abnormal Curvatures
• Scoliosis- abnormal side
to side
• Kyphosis-Exaggerated
posterior curvature of
thoracic vertebraeosteoporosis
• Lordosis-exaggerated
posterior curve of lumbar
• Pregnancy, pot belly
Typical Vertebrae
• Body- weight bearing
anterior
• Vertebral Arch- join
the laminae and
pedicles posterior
• Vertebral Foramencanal that spinal cord
passes
• Transverse Process- 2
lateral projections
from the arch
Typical vertebrae
• Spinal Processsingle projection
from posterior arch
• Superior and
Inferior Articular
Processes- paired
projections lateral
to the foramen
allows the vertebrae
to join each other
Cervical Vertebrae - neck
C1 - ATLAS
• No body
• receives the
occipital
condyles
• Allows the “yes”
nod
Cervical vertebrae
C-2 - AXIS
• Has an upright
pivot called dens
or odontoid
process
• Allows rotation“no”
Cervical vertebrae
C-3 to C- 7
• Small
• Short bifid spinous process
• Transverse processes contain
foramen for arteries
Thoracic Vertebrae
T1 – T12
• Larger heart
shaped body
• Long spinous
process-points
downward
• 2 costal facets on
either side for ribs
Thoracic Vertebrae
Lumbar vertebrae
L1 – L5
• Massive
body
• Hatchet like
spinous
process
• Takes most
stress
Sacrum 5 fused vertebrae
• Posterior Pelvis
• wing like
• Lateral
articulation with
hip
• Medial Sacral
Crest- posterior
fused spinous
processes
Sacrum
• Sacral foraminalateral to crest
• Sacral Canaldown the center
• Sacral Hiatusinferior opening
Coccyx 3-5 fused vertebrae
• tailbone
Bony Thorax
• Ribs
• Sternum
• Thoracic
vertebrae
Sternum
• Manubrium- jugular
notch
• Body- sternal angle
(3rd rib)
• Xiphoid Processsmall point at
bottom
Xiphoid
• The Xiphoid
process can
cause damage
because of the
location of the
liver
Costal Cartilage
• The costal
cartilage
attaches the
ribs to the
sternumhyaline
cartilage
Ribs- 12 pairs
• True ribs-are
connected to the
sternumvertebrosternal # 1-7
• Posterior – attached
to thoracic vertebrae
1-7
• Anterior- attached to
sternum
• False Ribs- are not
connected directly to
the sternum
• Ribs 8-10 are called
false
• Ribs 8-10 are called
vertebrochondral
• Posterior- attaches to
vertebrae
• Anterior- attaches to
cartilage
• Floating Ribs- ribs 11
& 12
• They are not
connected in the
anterior, only the
posterior
• Posterior- vertebrae
• Anterior- nothing
Ribs- flat bones
• Head- meets with
the body of the
thoracic vertebrae
• Neck- meets with
the transverse
process of the
thoracic vertebrae
• Shaft- angles
downward