Union Rate and Complications in Spine Fusion with Recombinant Human Bone Morphogenetic Protein-7: Systematic Review and Meta-Analysis

Abstract

Study Design Systematic review and meta-analysis. Objective: The objective of this meta-analysis was to evaluate the current best evidence to assess effectiveness and safety of recombinant human bone morphogenetic protein-7 (rhBMP-7) as a biological stimulant in spine fusion. Methods: Studies were included if they reported on outcomes after spine fusion with rhBMP-7. The data was synthesized using Mantel-Haenszel pooled risk ratios (RRs) with 95% confidence intervals (CIs). Main end points were union rate, overall complications, postoperative back and leg pain, revision rates, and new-onset cancer. Results: Our search produced 796 studies, 6 of which were eligible for inclusion. These studies report on a total of 442 patients (328 experimental, 114 controls) with a mean age of 59 ± 11 years. Our analysis showed no statistically significant differences in union rates (RR 0.97, 95% CI 0.84 to 1.11, p = 0.247), overall complications (RR 0.92, 95% CI 0.71 to 1.20, p = 0.545), postoperative back and leg pain (RR 1.03, 95% CI 0.48 to 2.19, p = 0.941), or revision rate (RR 0.81, 95% CI 0.47 to 1.40, p = 0.449). There was a mathematical indicator of increased tumor rates, but with only one case, the clinical meaningfulness of this finding is questionable. Conclusion: We were not able to find data in support of the use of rhBMP-7 for spine fusion. We found no evidence for increased complication or revision rates with rhBMP-7. On the other hand, we also found no evidence in support of improved union rates.