Correlative measurement of anterior margin of the anulus for surgical planning.

Abstract

This study was a retrospective anatomic correlation of intervertebral disc dimensions with current surgical guidelines. To develop safer guidelines for disc instrumentation. Anterior perforation of the anulus fibrosus and injury to intra-abdominal structures is a known complication of lumbar discectomy. Coplanar magnetic resonance imaging of the lumbar intervertebral discs could decrease the rate of complication using axial 11-weighted scans. Three measurements through the intervertebral discs of the lumbar spine were taken in 50 patients. These were correlated with current surgical guidelines for lumbar instrumentation. Most of the measurements exceeded the current suggested guidelines for instrumentation at 3 cm. Current guidelines for introduction of instruments into the lumbar disc spaces should be reevaluated. Appropriate measurements should be made on an individual basis.