Lumbar Decompression with and without Fusion for Lumbar Stenosis with Spondylolisthesis: A Cost Utility Analysis.

STUDY DESIGN:Markov model. OBJECTIVE:To compare the cost-effectiveness of lumbar decompression alone (DA) with lumbar decompression with fusion (DF) for the management of adults undergoing surgery for lumbar stenosis with associated degenerative spondylolisthesis. SUMMARY OF BACKGROUND DATA:Rates of lumbar fusion have increased for all indications in the United States over the last 20 years. Recent randomized controlled trial data, however, have suggested comparable functional outcomes and lower reoperation rates for lumbar decompression and fusion as compared to lumbar decompression alone in the treatment of lumbar stenosis with degenerative spondylolisthesis. MATERIALS AND METHODS:A multi-state Markov model was constructed from the U.S. payer perspective of a hypothetical cohort of patients with LSS requiring surgery. Data regarding clinical improvement, costs, and reoperation were generated from contemporary randomized trial evidence, meta-analyses of recent prospective studies, and large retrospective cohorts. Base case, one-way sensitivity analysis, and probabilistic sensitivity analyses were conducted and results were compared to a willingness to pay threshold of $100,000 (in 2022 USD) over a 2-year time horizon. A discount rate of 3% was utilized. RESULTS:The incremental cost and utility of decompression with fusion relative to decompression alone were $12,778 and 0.00529 QALYs. The corresponding ICER of $2,416,281 far exceeded a willingness to pay threshold of $100,000. In sensitivity analysis, the results varied the most with respect to rate of improvement after lumbar decompression alone, rate of improvement after lumbar decompression and fusion, and odds ratio of reoperation between the two groups. 0% of one-way and probabilistic sensitivity analyses achieved cost-effectiveness at the willingness to pay threshold. CONCLUSIONS:Within the context of contemporary surgical data, DF is not cost effective compared with DA in the surgical management of LSS over a 2-year time horizon.