Magnetic resonance assessment of the distribution of lumbar spine disc degenerative changes.

The lumbar spine magnetic resonance (MR) studies in 246 consecutive patients who suffered from persistent back and leg pain were evaluated for the degree of degenerative disc disease and the presence of disc bulging, prolapse, or herniation. No patient had a history of previous back surgery. In those patients, degenerative disc changes increased with age until the fifth decade of life, after which a relatively similar proportion of patients had degenerative disc disease. Significant dehydration and degeneration occurred in less than 5% of the upper two disc spaces while L4/5 and L5/S1 had marked changes in greater than 20%. Prolapse and herniation progressively increased with each lower interspace, where at L5/S1 it was present in nearly one-third of the patients. Although a few patients had disc prolapse or herniation with a nondegenerated disc, there was a relationship between the presence of disc degeneration and prolapse or herniation.