title: The form and structure of the extruded disc.
abstract: There are no detailed data in literature concerning the histologic nature of the sequestered (extruded) lumbar disc, and on the frequency with which an extruded fragment, a prolapse or a protrusion are found at surgery. A prospective analysis of 100 consecutive cases of sequestered lumbar disc herniation submitted to surgical treatment revealed this group to represent 28.6% of all cases operated on for lumbar disc herniation. Patients (both male and female) with sequestered lumbar discs are significantly older than those with prolapsed (P < 0.01) and protruded (P < 0.001) discs. Single extruded fragments (n = 68) were twice as frequent as multiple ones (n = 32). The general belief that a 'sequestered (extruded) disc' is almost invariably composed of nucleus pulposus is not substantiated by this study: In 54 cases the extruded fragment consisted predominantly of nucleus material, whereas in 44 cases it consisted mainly of end-plate material. Multiple as well as recurrent sequestered fragments almost always consist of end-plate material. These findings may reflect the result of metabolic alterations in the course of disc degeneration.
authors: Department of Neurosurgery, Klinikum Steglitz, Free University of Berlin, Germany.
authors: M
authors: M
authors: Brock
authors: S
authors: S
authors: Patt
authors: H M
authors: HM
authors: Mayer
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology*; D007405:Intervertebral Disc Displacement / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery; D008159:Lumbar Vertebrae / Q000473:pathology*; D008297:Male; D011446:Prospective Studies