Clinicopathologic study of changes in prolapsed intervertebral disks

To study the various factors that might influence the detection of edge neovascularization that is seen in prolapsed intervertebral disks, clinical features of 112 patients were reviewed. Edge neovascularization, which was seen in nearly one half of surgical specimens, was identified more frequently in lumbar disks (61.2%) than in cervical disks (3.8%). Although the characteristic change was more likely to be found in entirely than partially submitted specimens, the difference was not statistically significant. There was a direct relationship between neovascularization and the duration of symptoms. The frequency of finding the specific change increased from 12.5% in patients with disease for less than a month to 82% of patients who had symptoms for 6 months or more. Specific changes in prolapsed disks probably reflect a reparative phenomenon that is influenced by the degree and duration of mechanical forces.