Correlative Measurement of Anterior Margin of the Anulus for Surgical Planning

Abstract

Study Design 

This study was a retrospective anatomic correlation of intervertebral disc dimensions with current surgical guidelines.

Objectives 

To develop safer guidelines for disc instrumentation.

Summary of Background Data 

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 T1-weighted scans.

Methods 

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.

Results 

Most of the measurements exceeded the current suggested guidelines for instrumentation at 3 cm.

Conclusions 

Current guidelines for introduction of instruments into the lumbar disc spaces should be reevaluated. Appropriate measurements should be made on an individual basis.