Cervical Anatomy and Pathology - Midlumbar Spine

Midsagittal section through the midlumbar spine of a 64–year–old female cadaver. The spine portion had been frozen in situ during routine autopsy in the supine position. The veins posterior to the spine are engorged with cruor mortis. Yet the spinal cord closely follows the vertebral bodies. All discs show degenerative changes, the disc between T9 and T10 is completely resorbed and the cartilaginous endplates have fused. On the most spondylotic segments the anterior longitudinal ligament is thicker than in the less degenerated segments. Normally thoracic discs have a perfectly straight posterior margin, not even in extension do they bulge into the vertebral canal. Of particular surgical interest is the relationship of the laminae to the intervening ligamentum flavum The long slender spinous processes as well as the flat wide laminae all overlap like obliquely sloping shingles, completely hiding the ligamentum flavum. The latter attaches to the adjacent laminae in a consistent fashion: It inserts into the anteriorly and slightly inferiorly directed surface of the suprajacent lamina and into the upper rim (margin) of the infrajacent lamina. Viewed from the spinal canal (anteriorly) only a narrow band of bone is visible; the posterior wall of the spinal canal thus is predominantly elastic–ligamentous, yet shielded by the "hidden" lamina portion. Note that the veins behind the dura (belonging to the posterior internal venous plexus) are invariably located at the level of the bony lamina, not the ligamentum flavum.

©2000 Wolfgang Rauschning, M.D., Ph.D.
Professor of Clinical Anatomy
Academic University Hospital
Department of Orthopaedic Surgery
Uppsala, Sweden
Reproduction without permission is prohibited
http://www.akademiska.se/