Vertebral 'corner' defect associated with lumbar disk herniation shown by magnetic resonance imaging.

Two examples of a marked defect of the corner of the vertebral body adjacent to an intervertebral disk herniation are presented. The prevalence of this finding was assessed in 43 randomly selected patients with disk herniation (at 46 levels). None of these patients had such marked vertebral defects (moderate changes at 3 levels; minor in 23). Although the defects were seen more often in younger patients, adjacent to large herniations, and in those with substantial cranial or caudal migration, these associations did not reach statistical significance. However, the site of the defect, when associated with disk migration, correlated with the direction of the migration. It is considered likely that this defect is caused by a purely mechanical effect, but its possible relationship to developmental factors is discussed.