Variation in surgical decision making for degenerative spinal disorders. Part I: Lumbar spine

Study Design. Survey-based descriptive study. Objective. To study relationships between surgeon-specific factors and surgical approach to degenerative diseases of the lumbar spine. Summary of Background Data. Geographic variations in the rates of lumbar spine surgery are significant within the United States. Although surgeon density correlates with the rates of spine surgery, other reasons for variation such as surgeon age and training background are poorly understood. Methods. A total of 22 orthopedic surgeons and 8 neurosurgeons of varied ages and geographic regions answered questions regarding the need for surgery, surgical approach, and use of fusion and instrumentation for 5 simulated cases. Cases included: (1) multilevel stenosis without deformity or instability, (2) degenerative spondylolisthesis with stenosis, (3) isthmic (spondylolytic) spondylolisthesis with foraminal stenosis, (4) degenerative scoliosis with stenosis, and (5) recurrent stenosis following prior laminectomy without deformity or instability. The effects of surgeon age and training background on surgical decision making were analyzed using an independent samples t test and Fisher exact test, respectively. Results. Significant variation in treatment approach among surgeons was noted for all cases except the patient with lytic spondylolisthesis, for whom all surgeons recommended fusion. Orthopedists recommended fusion and instrumentation more often than neurosurgeons for all cases, reaching significance for degenerative scoliosis with stenosis (P=0.02 for both fusion and instrumentation). Younger surgeons were generally more likely to recommend instrumentation than their older peers, reaching significance for multilevel stenosis without deformity or instability and recurrent stenosis following prior laminectomy without deformity or instability (P=0.05 and 0.01, respectively). Conclusions. Variations in surgical approach to lumbar degenerative diseases may depend on a patient's clinical condition. This study found strong agreement in the approach to lytic spondylolisthesis but significant variation for other degenerative conditions of the lumbar spine. In addition, recommendation for fusion and instrumentation varied with surgeon age and training background. Previously documented geographic variations may result in part from a lack of consensus on appropriate treatment techniques for specific lumbar degenerative conditions, as well as surgeon-specific factors.