Closeup view of the midlumbar spinal canal
in a severely degenerated and stenotic specimen from an elderly male
adult who had a history of prolonged low back pain without radicular
symptoms. The intervertebral disc is completely resorbed. Behind the
vertebra above and below the ventral internal veins are engorged. At
the posterior aspect of the disc a beak–shaped spondylosis ridge
projects into the spinal canal. The bone of this projecting
osteophyte has a light color (sclerotic), note that the outermost
annulus fibrosus (darker color) is still present. Posteriorly the
loss of segmental height entails an approximation of the spinous
processes and laminae ("kissing spines"). The articulating surfaces
of this neoarthrosis are covered with cartilage and are also bounded
by bizarre osteophytes. Note also the effusion in the neoarthrosis
between the laminae. The interlaminar ligamentum flavum is probably
only thickened by retraction due to the redundance and "mushrooms"
into the spinal canal and compresses the traversing intrathecal root
against the hard spondylophytic beak. It is obvious that the root
still is inside the thecal sac, therefore the compression is more
medial than only in the foramen and lateral recess.
©2000 Wolfgang Rauschning, M.D., Ph.D.
Professor of Clinical Anatomy
Department of Orthopaedic Surgery
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