Perforation of the anterior annulus fibrosus during operation for prolapsed disc.

The condition of the anterior portion of the prolapsed lumbar disc and the possible peroperative lesion of this structure was studied by peroperative discography. In 3 of 25 patients leakage of contrast medium anterior to the vertebral column occurred after evacuation of the nucleus pulposus. This finding may be taken as an intimation of structural weakness and vulnerability of the anterior part of the annulus fibrosus of the posteriorly herniated disc.