Trends of spinal fusion surgery in Australia: 1997 to 2006.

BACKGROUND: This study aims to explore the trend in spine fusion surgery in Australia over the past 10 years, and to explore the possible influence of health insurance status (private versus public) on the rate of surgery. METHODS: Data pertaining to the rate of lumbar spine fusion from 1997 to 2006 were collected from Inpatient Statistics Collection of NSW Health, Medicare Australia Statistics and the Australian Bureau of Statistics. Data on total hip and total knee arthroplasties were collected to provide a comparator. RESULTS: The number of publicly performed spinal fusion procedures increased by 2% from 1997 to 2006. In comparison, privately performed spinal fusion procedures increased by 167% over the same 10-year period. In 2006, spine fusion surgery was 10.8 times more likely to be done in the private sector than in the public sector, compared with corresponding figures of 4.2 times and 3.0 times for knee replacement and hip replacement, respectively. Waiting list data showed no increase in demand for spine fusion surgery in the public sector. CONCLUSION: There is a disproportionately high rate of lumbar spine fusion surgery performed in the private sector, given the rate of private insurance. The rate of increase was found to be higher than that for hip or knee arthroplasty procedures. Possible explanations for this difference include: over-servicing in the private sector, under-servicing in the public sector, differences in medical referral patterns, surgeon and patient preferences and financial incentives.