Surgical outcome of posterior lumbar interbody fusion with pedicle screw fixation for lumbar spondylolisthesis

Introduction: Problems of lumbar spondylolisthesis treatment are 1. Many surgical tactics, 2. Elderly patient, 3. Osteoporosis, 4. Complications and 5. Recurrence of the symptoms. PLIF (posterior lumbar interbody fusion) and PS (pedicle screw) fixation technique for lumbar spondylolisthesis provide good patient satisfaction. Good outcome has been reported by only laminectomy alone, but patient satisfaction becomes worse year after year. The role of instrumentation for lumbar spondylolisthesis is decompression of the nerve root, correction of lumbar pathologies, bony fusion and early mobilization. We show our surgical technique and long term outcome of PLIF with PS for lumbar spondylolisthesis. Material and Methods: 350 cases of lumbar spondylolisthesis were operated on in Department of Neurosurgery, Fujita Health University during the period of from December 1992 to August 2008. Patient background: age 16-84 years old (mean 62.5), Gender: male 153, female 197. Follow-up period 1-180 months (mean 61.2). Degenerative: 255, Isthmic: 63, Dysplastic: 10, Fracture: 5 and scoliosis 16 cases. Surgical procedure was PS with interbody fusion cage: 331, Hybrid cage (titanium cage with hydroxyapatite) 314, PS with Cerabone: 2 and PS with autograft: 17. CT was done to evaluate bony fusion postoperatively. Results: Post operative improvements by JOA (Japan Orthopedic Association) score is 11.4 before surgery, 24.1 (post op. within 2years), 25.4 (post op. 2-5years), 25.0 (post op. 5-10years) and 22.4 (post op. 10-15years). Significant improvements were observed in %Slip and Slip angle but no remarkable change was observed in lumbar lordotic angle by postoperative X-ray evaluation. Complications: No root injury, and systemic complication except 4 cases of CSF leakage during surgery. Two cases were reoperated in whom cage with autograft migration due to pseudoarthrosis. Two cases had to undergo screw and cage system removal due to infection. Two cases of adjacent level stenosis had to undergo operation 10 tears after surgery in this study. Conclusions: Rigid fixation (PLIF+ PS) technique for lumbar spondylolisthesis provide good surgical result for over 15years. Minimum invasive surgery is popular but this technique achieved good satisfaction for patient and prevent malpractice.