Anatomy of the Vertebral Column
The vertebral column
Human vertebral column composed of approximately 31 vertebrae
Five vertebral
regions
7 Cervical (neck)
12 Thoracic
(vertebrae with ribs)
5 Lumbar (lower
back)
5 Sacral (all
fused into one unit, articulate with pelvis)
2-3 coccygeal vertebrae (all fused into one unit)
A pair of spinal
nerves (left & right) emerges from between successive vertebrae
Vertebral morphology
All vertebrae have
the same basic parts
Body
Bears weight in
articulation with vertebrae above and below
Neural arch
Protects spinal
cord
Articular processes
Articulation of
neural arch with vertebrae above and below (called zygopophyses)
Spinous process
Muscular and ligamentous attachment
Regional distinctions - cervical
Cervical vertebrae
have thin bodies and a foramen in the transverse process
The first and
second cervical vertebrae are specialized to articulate with, and move the
skull
C1- the Atlas has no body,
but has two arches (anterior & posterior)
It has articular facets for the skull superiorly that allow for
nodding of the head
It has articular facets for the axis (C2) inferiorly
Regional distinctions - cervical
C2
?the Axis - has a specialized projection from its body to articulate
with the Atlas.
Dens, or odontoid (tooth like) process
The dens is attached to the anterior arch of the Atlas by
ligaments.
This articulation
allows rotation of the head.
Regional distinctions - cervical
Facet joints of
vertebrae 3-7 are specialized to allow rotation of the head and flexion and
extension of the neck
The vertebral
artery passes through the transverse foramina of C6-C1, taking blood to the
brain.
Regional distinctions - thoracic
Thoracic vertebrae
have larger bodies than cervical vertebrae
Thoracic vertebrae
bear two articular facets for each rib
One facet on the
body, another on the transverse process
Thoracic vertebrae
have a long, inferiorly inclined spinous process
Regional distinctions - thoracic
Articular facets of thoracic vertebrae allow flexion,
extension and rotational movements of the trunk
Regional distinctions - lumbar
Lumbar vertebrae
have the largest bodies ? bear
much of the weight of the body.
They have no ribs,
but have prominent transverse processes.
Articular facets allow flexion and exension,
but limit rotation.
Regional distinctions - sacral
The five sacral
vertebrae are fused into a single unit.
Together they
articulate to the coxal bones to form the bony pelvis
They have foramina
dorsally and ventrally for the posterior and anterior rami
of the spinal nerves
Regional distinctions - coccygeal
Tail vertebrae
Little function in
humans
Usually transmit
one pair of coccygeal nerves
The vertebrae together
Collectively, the
vertebrae from all five regions compose the vertebral column
An intervertebral disc is found between each of the vertebral
bodies (except for C1 & C2 and the fused sacrals)
Differences in the
shapes of the body and disc contribute to the normal vertebral curvature.
Soft tissue connections
Intervertebral discs
Annulus fibrosus
Nucleus pulposus
Longitudinal
ligaments
Anterior
posterior
Ligamenta flava
Facet joints
Interspinous ligaments