The authors analysed 92 patients who were operated with laminectomy and disectomy for herniated lumbar discs from August 1984 to July 1986 at the Depart. of neurosurgery, Korea University College of Medicine. The authors tried to grade the degeneration of nucleus pulposus pathologically in accordance with the severity of collagenosis and to correlate between these gradings with clinical and radiologic findings. The results were as follows, 1) Collagenosis seemed to be normal aging process of lumbar discs. 2) Duration of clinical symptoms, narrowing of the disc space and spur formation were correlated with the severity of collagenosis. 3) Sequestered discs seemed to promote the progression of collagenosis.