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Lower lumbar spine of an old man with
pronounced disc degenerations L4–L5 and L5–S1. The intact torso had
been frozen in axial rotation. At L4–L5 the root traversing the
lateral recess is severely compressed. Anteriorly there is a
motion–induced (functional) retrolisthesis of L4 on L5 that also
causes the grossly disrupted disc to move posteriorly. Posteriorly
the lateral portion of the lamina and the most medial portion of the
superior articular process of L5 (5) have moved anteriorly due to
the rotation and squeeze the L5 root against the disc. Note the
gaping (vacuum phenomenon) in the joint. At L5–S I degenerated disc
material pushes the outermost annulus posteriorly and also has
caused detachment of (thickened) periosteum from the vertebral body
(contained disc herniation). At the lower insertion of the annulus
a marked sclerotic spondylophyte projects posteriorly, compressing
the SI root against the infolding ligamentum flavum.
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©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/
