Efficacy and Safety of Osteobiologics for Lumbar Spinal Fusion: A Systematic Review and Network Meta-Analysis

Background: Lumbar spinal fusion (LSF) is a common surgical procedure for treating lumbar degenerative conditions. The use of osteobiologics to enhance fusion has emerged as a promising alternative to address the limitations of autologous iliac crest bone graft (AICBG), but their comparative efficacy and safety remain unclear. This systematic review and network meta-analysis (NMA) aimed to assess the fusion rates, safety profiles, and clinical outcomes of the use of osteobiologics in LSF. Methods: PubMed/MEDLINE and Scopus databases were searched for randomized controlled trials (RCTs) comparing different osteobiologics to AICBG in LSF. Data on fusion rates, complications, pain, disability, blood loss, operative time, and length of stay (LOS) were extracted. The risk of bias was evaluated using the Cochrane Risk of Bias-2 tool, and the certainty of evidence was assessed using the GRADE framework. The NMA was performed using a frequentist random-effects model to compare the efficacy and safety of various osteobiologics, along with associated perioperative and clinical outcomes. Results: Forty-three RCTs including a total of 3,823 patients were identified. The use of rhBMP-2 (recombinant human bone morphogenetic protein-2) significantly improved fusion rates (odds ratio [OR]: 3.71; 95% confidence interval [CI]: 2.59 to 5.32; p < 0.0001) and reduced complications (OR: 0.30; 95% CI: 0.13 to 0.68; p < 0.0001) compared with AICBG, with moderate certainty of the evidence. Other osteobiologics, including ABM/P-15 (anorganic bone matrix/15-amino acid peptide fragment) and allograft, demonstrated reduced complication rates, although the quality of the evidence was low to very low. No significant differences were observed for pain, disability, or LOS. The use of rhBMP-2, autologous local bone, and silicate-substituted calcium phosphate was associated with decreased operative time, with rhBMP-2 additionally associated with lower intraoperative blood loss. Conclusions: Use of rhBMP-2 was associated with significantly higher fusion and lower complication rates compared with AICBG, as well as decreased operative time and blood loss. Other osteobiologics may also offer benefits, but the supporting evidence is low-quality and limited by the notable underrepresentation of these materials in the published literature. Level of Evidence: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.