Surgical Management of Patients with Isthmic Spondylolisthesis with Transpedicular Screw Fixation and Posterior Lumbar Interbody Fusion using Posterior Movable Segment

ABSTRACT

Twenty three patients with isthmic spondylolisthesis were operated on from December 1993 to June 1995. There were 14 female and 9 male patients and the average age of the patients was 50(ranging 20-67) years old. Symptoms in the lower extremities had been present for 3 months to 10 years, although varying degrees of back pain had existed for longer periods. Disability was caused mainly by claudication in 20 patients. Diagnostic studies included plain films, tomography, CT scaning, and MRI. Single interspace was involved in 18 patients, and in five patients, two interspaces were involved. After wide decompression and discectomy, stabilization was reestablished by segmental pedicular screw fixation device(Diapason(R) pedicular system) and interbody fusion using posterior movable segment as graft material. Between 6 to 24 months postoperatively, all patients exhibited radiographic fusion. The results were excellent in 12 cases, good in 8 cases and fair in 3 cases. The authors believe that full four nerve roots decompression, pedicular screw fixation. Posterior lumbar interbody fusion using movable segment as graft material, and prevention of nerve root traction injury during insertion of graft bone are important points to get good post-operative results.