The who, what and when of surgery for the degenerative lumbar spine: a population-based study of surgeon factors, surgical procedures, recent trends and reoperation rates.

BACKGROUND: Degenerative disease of the lumbar spine (DLS) is a common condition for which surgery can be beneficial in selected patients. With recent surgical trends toward more focused subspecialty training, it is unclear how characteristics of the surgical consultant may impact on treatment and reoperations. Our objective was to understand the relations between surgeon factors (who), surgical procedures (what) and recent trends (when) and their influence on reoperations for DLS surgery. METHODS: We performed a longitudinal population-based study using administrative databases including all patients aged 50 years and older who underwent surgery for DLS. We collected data on surgeon characteristics (specialty, volume), index procedures (decompressions, fusions) and reoperations. RESULTS: We identified 6128 patients who underwent surgery for DLS (4200 who had decompressions, 1928 who had fusions). We observed an increasing proportion of fusions over decompressions while the per capita surgeon supply declined. Orthopedic specialty and higher surgical volume were associated with a higher proportion of fusions (p < 0.001). The overall reoperation rate was 10.6%. Reoperations were more frequent in patients who had decompressions than those who had fusions at 2 years (5.4% v. 3.8%, odds ratio 1.4, p < 0.013), but not over the long-term. Long-term survival analysis demonstrated that a lower surgical volume was related to a higher reoperation rate (hazard ratio 1.28, p = 0.038). CONCLUSION: Lumbar spinal fusion rates for DLS have been increasing in Ontario. There is wide variation in surgical procedures between specialty and volume: namely high-volume and orthopedic surgeons have higer fusion rates than other surgeons. We observed better long-term survival among patients of high-volume surgeons. Referring physicians should be aware that the choice of surgical consultant may influence patients' treatments and outcomes. With increasing rates of spinal surgery, the efficacy and cost benefit of current surgical options require ongoing study.