The base plates and upper plates of the lumbar vertebrae are large and bean-shaped, the vertebral foramen has a small, triangular cross-section and the thick spinous processes are positioned horizontally.
The varying requirements with regards to mobility and load bearing capacity have resulted in different vertebral forms.
However, the cervical, thoracic and lumbar vertebrae still show structures common to all vertebral bodies. The vertebra consists of a hard external bony layer, the compacta, and the spongy inner bone substance, the spongiosa. .
The arch located at the rear (dorsal) (3), the two transverse processes (2) and the spinous process (1) together with the pedicle (4) and the articular processes (5) form the posterior element that, with all its parts, provides important points of attachment for back muscles and represents a major element of mobility. The vertebral body (7) is at the front or ventral (towards the abdominal or thoracic cavity) and, together with the intervertebral discs, fulfils the main function of the load bearing column. The vertebral foramen (6) lies between the vertebral body and the vertebral arch. Taken together, all of the vertebral foramina line up to form the spinal (or vertebral) canal (canalis vertebralis), which contains and protects the spinal cord with its emerging nerves. The intervertebral foramina (9) on both sides of the vertebral body are formed by the inferior vertebral notch (10) and the superior vertebral notch (11). A spinal nerve from the spinal cord emerges through each of
these openings along with several blood vessels.
The thoracic vertebral bodies feature the superior costal facets (8), to which the ribs are attached.
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