Avoiding neurologic complications following ligation of the segmental vessels during anterior instrumentation of the thoracolumbar spine

STUDY DESIGN. A retrospective evaluation of anterior instrumentation of the vertebral bodies in the thoracolumbar spine. OBJECTIVE. To evaluate the possibility of preserving the segmental vessels following anterior instrumentation. SUMMARY OF BACKGROUND DATA. Occlusion of the segmental vessels, routinely performed during anterior spine instrumentation, might cause neurologic injury secondary to cord ischemia. METHODS. The medical data of 29 patients following anterior instrumentation of the vertebral bodies at the thoracolumbar spine were reviewed. All underwent surgery recently when we decided to preserve the segmental vessels whenever possible. We sought the reasons that enabled us to do so regarding age, gender, underlying pathology, surgical technique, operation duration, instrumentation type and size, and location in the vertebral body. RESULTS. In only 7 patients, fused between T10 and L5, were we able to preserve the segmental vessels. All were instrumented with one 6.25-7-mm wide screw in each vertebral body connected by one rod, approximately half the screws above and half below the segmental vessels. In 22 patients, we were unable to preserve the vessels due to the need to insert 2 screws or a large threaded wide vertebral cage into each vertebra. CONCLUSIONS. There is adequate space anteriorly in the vertebral body, above and below the segmental vessels, for the insertion of one screw, even with staples.