Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) to Prevent Symptomatic Pseudarthrosis in Posterolateral Lumbar Fusion

Study Design. A break-even cost-effective analysis Objective. To evaluate the cost-effectiveness of recombinant human bone morphogenetic protein–2 (rh-BMP-2) for preventing symptomatic pseudarthrosis requiring revision surgery in posterolateral lumbar fusion. Summary of Background Data. Spinal fusion rates differ across surgical techniques and are influenced by approach, graft selection, and patient factors. Although rh-BMP-2 has been shown to improve fusion rates, its widespread use remains limited by high upfront costs and uncertainty regarding cost-effectiveness. Methods. A break-even analysis framework was used to determine the absolute risk reduction (ARR) in symptomatic pseudarthrosis required for rh-BMP-2 to be cost-effective. Model inputs were derived from published literature and included low (2%) and high (15%) baseline symptomatic pseudarthrosis rates requiring revision surgery, rh-BMP-2 costs before and after surgeon cost awareness, and two-year costs of treating pseudarthrosis using combined direct and indirect cost models. Base-case and one-way sensitivity analyses were performed to assess the impact of baseline pseudarthrosis risk, rh-BMP-2 cost, revision surgery cost, and surgeon cost awareness, defined as adjusting rhBMP-2 dosages to reduce surgical costs. Break-even number needed to treat (NNT) values were calculated. Results. Rh-BMP-2 was cost-effective only at high baseline symptomatic pseudarthrosis rates across both cost models. Using surgical-only revision costs, rh-BMP-2 was cost-effective at high baseline pseudarthrosis rates with an ARR of 14.32% (NNT = 7) prior to surgeon cost awareness and 7.89% (NNT = 13) after cost awareness. At low baseline pseudarthrosis rates, rh-BMP-2 was not cost-effective regardless of product cost. Sensitivity analyses demonstrated that surgeon cost awareness and higher revision costs expanded scenarios in which rh-BMP-2 was cost-effective. Conclusion. Rh-BMP-2 is most likely to be cost-effective in posterolateral lumbar fusion among patients with a high baseline risk of pseudarthrosis, particularly with substantial revision costs and surgeon cost awareness. These findings support a selective, risk-stratified approach to rh-BMP-2 utilization. Level of Evidence. III