Is fusion indicated for lumbar spinal disorders?

STUDY DESIGN: A review of relevant literature and clinical experience with lumbar spinal disorder.

OBJECTIVES: To discuss the indications for fusions and lumbar spinal disorders.

SUMMARY OF BACKGROUND DATA: Fusion of the lumbar spine is performed frequently, but indications have not been defined clearly. The literature and the authors' experience with these indications are reviewed.

METHODS: A comprehensive review of the literature and the authors' clinical experience with lumbar spinal instability was critically examined. Specifically, the role of fusion, with or without instrumentation, versus decompression alone was assessed. From this, a set of definitive and relative indications for spinal arthrodesis in a variety of disorders of the lumbar spine could be established.

RESULTS: Once the diagnosis of lumbar spinal instability is established, fusion is indicated. However, fusion without spinal instrumentation has a high pseudarthrosis rate and poorer patient outcome. This spinal instrumentation should be used as an adjunct when considering spinal arthrodesis.

CONCLUSIONS: Definitive indications for spinal fusions are trauma, tumor and infection, iatrogenic instability, or ischemic spondylolisthesis. Relative indications for fusions are degenerative spondylolisthesis, abnormal movement visualized on dynamic films with appropriate pain or neurologic deficit, and mechanical pain. Lumbar fusion is rarely indicated for routine discectomy, abnormal results of radiography without appropriate clinical findings, or stable spinal stenosis.