An Ultrastructral Study in the Prolapsed Intervertebral Disk

ABSTRACT

The study was carried out to investigate the ultrastructural changes of nucleus pulposus of prolapsed disc and to evaluate the characteristic histologic changes of prolapsed intervertebral disc. Histologic findings of curetted fibrocartilage from 33 discs having documented disc prolapse into spinal canal were reviewed. Light microscopically, neovascularization, splitting, myxoid degeneration, cystic change, chondrocytic cloning and granular change were observed. Among these microscopic features, splitting, myxoid degeneration and chondrocytic cloning were observed in all of the cases, and the remaining other features were noted in more than 50% of the cases. Electron microscopically, the nucleus pulposus showed a few viable notochord cells, which had abundant cytoplasmic organelles such as glycogen particles, mitochondria, rough endoplasmic reticulum and lipid droplets. Numerous cytoplasmic processes are noted. Then matrix showed fine fibrils and irregular shaped electron dense granules and fragmented collagen fibers.