The results of posterolateral lumbar fusion with bone chips from laminectomy in patients with lumbar spondylolisthesis.

BACKGROUND This study was undertaken to assess the radiologic outcome of spinal fusion, with bone chips from laminectomy in patients with lumbar spondylolisthesis. METHODS From January 1993 to September 2001, 95 patients with lumbar spondylolisthesis were managed and followed up well at our Orthopedic Division. All patients presented with persistent low back pain, radiculopathy and claudication. The diagnosis of lumbar spondylolisthesis was confirmed by plain radiographs of the lumbar spine, with lumbar spine computed tomography scan (CT-scan) performed to identify other associated conditions. A near total posterior decompression laminectomy with foraminotomy and posterolateral lumbar fusion using bone chips from laminectomy as bone graft and reduction of the vertebral slip using transpedicle screws with Arbeitsgemeinschaft für Osteosynthesefragen spinal fixators and Trifix Reduction Fixation spinal system implants, were instituted. Additional disectomies were performed in several patients with disc rupture as confirmed by CT-scan. Fusion was then assessed by plain lumbar radiographs done at 4, 8, and 24 months after operation. RESULTS The outcome was good, with 88 (92.6%) cases attaining solid fusion, while failed fusion was noted in 7 (7.4%) cases. CONCLUSIONS Proper decortication of the posterolateral vertebral gutter with removal of all soft tissues attached to the bone chips prior to the placement of bone graft were noted to be the most significant factors for spinal fusion. Fusion rate with bone chips from laminectomy was shown to be comparable to that of the iliac crest bone graft.