Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) to Prevent Symptomatic Pseudarthrosis in Posterolateral Lumbar Fusion: A Break-Even Cost-Effective Analysis.

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.