Degenerated lumbar intervertebral disc. A morphological study.
According to many investigators, lumbar disc herniation is formed by the nucleus pulposus displaced to the vertebral canal through the cracks in the annulus fibrosus as a final result of disc degeneration. Specimens obtained during 187 disc surgeries were studied to identify the morphological nature of various forms of disc herniation, especially protrusion and prolapse. In 29% of cases the herniated part was annulus fibrosus and in 21.5% cases the annulus fibrosus was seriously involved. Simultaneously 308 autopsy specimens were studied. On gross examination the signs of degeneration were advanced in 82, and strongly pronounced in 42. In 15 specimens, aged 40 years or older, fibre bundles were reversed to normal convex orientation producing annulus fibrosus bulge. Microscopic examination showed pronounced myxomatous degeneration within the annulus fibrosus. In these circumstances, we believe that general opinion must be verified, because in some herniations the nuclei pulposus are not involved and herniations are solely prolapses of annulus fibrosus. So, the lumbar intervertebral disc herniation should be classified on the basis of histological examinations as a herniation of nucleus pulposus, herniation of annulus fibrosus or as a mixed type herniation where both disc elements are involved.
Łebkowski
Wojciech J
WJ
Department of Neurosurgery, Medical Academy, Białystok. wleb@amb.ac.bialystok.pl
Dziecioł
Janusz
J
D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology* / Q000601:surgery; D007405:Intervertebral Disc Displacement / Q000473:pathology* / Q000601:surgery; D008159:Lumbar Vertebrae / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged