B • ANATOMY, NEUROPATHOLOGY AND REGENERATION
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vertebrae and the last between 5th lumbar vertebra and sacrum. Altogether there are 23
intervertebral discs. The vertebral column showing ventral convex curves in the cervical
and lumbar regions and a concave curve in the thorax region is connected cephalad
through the atlas with the skull and caudal through the 5th lumbar vertebra with the os
sacrum which is provided with 5 vertebrae and which in turn is connected with the 4
vertebrae of the os coccyx (Figs, ica and b). Fig. loa shows the foramina interverte-
bralia, the most proximal between the 2nd and 3rd cervical vertebrae, the most distal
between the 5th lumbar vertebra and sacrum. There is one intervertebral foramen on
each side between two neighbouring vertebrae providing the communication of the
spinal nerves and vessels with the spinal cord and its meninges.
The individual vertebrae consist of the anterior part, the vertebral body, and the
posterior part, the vertebral arch consisting of a pair of pedicles and a pair of laminae and
is provided with seven processes four articular, two transverse and one spinous process.
The vertebral bodies and arches form the vertebral canal which contains and protects
the spinal cord. In the thoracic region each rib of the thoracic cage also forms an essential
part of each vertebral arch.
There are two superior and two inferior articular processes which arise from the
junction of the laminae and pedicles and are in contact with the corresponding processes
of the adjacent vertebrae. Their function is to control and restrict the range of vertebral
movement.
The transverse processes spring laterally from the junctions of the pedicles and
laminae. They provide the attachment of ligaments and muscles and while, in the thoracic
region they limit the movements of the ribs, they act as a fulcrum for lateral and rotatory
movements of the vertebrae in the other regions.
The spinous processes originating from the junction of the laminae and projecting
in backward and downward directions also serve the attachments of ligaments and
muscles.
There are great variations in size, shape and direction of the individual vertebrae
in accordance with their functions as levers of extension, flexion and rotatory movements
in the various regions of the vertebral column. Figs. 11-16 demonstrate the main
varieties of vertebrae at various levels of the spine.
tuberculitm postering
arcus posterior
processus
transversus
margo medialis
foveae articularis
superioris
V
/
fovea articularis inferior
arcus anterior /
"**<;
.^g^^fovca dent is
nihcrciilum antenus
FIG. ii. Atlas, caudal view (Sobotta-Bechcr).
