Background:

The impact of bone morphogenetic protein-2 compared to autologous iliac crest bone graft to improve fusion rates for the posterolateral fusion of the lumbar spine remains inconclusive. This meta-analysis was performed to evaluate this relationship.

Methods:

A systematic-literature search up-to May 2020 was performed and 14 studies were detected with 1516 subjects with 789 of them were bone morphogenetic protein-2 and 727 of them were autologous iliac crest bone graft. They reported relationships between bone morphogenetic protein-2 and autologous iliac crest bone graft on fusion rates for the posterolateral fusion of the lumbar spine. Odds ratio (OR) with 95% confidence intervals (CIs) was calculated comparing the bone morphogenetic protein-2 or autologous iliac crest bone graft on the posterolateral fusion of the lumbar spine risks using the dichotomous and continuous method with a random or fixed-effect model.

Results:

Bone morphogenetic protein-2 had significantly higher fusion rates (OR, 4.19; 95% CI, 2.82-6.20, p<0.001); lower surgery time (OR, -26.64; 95% CI, -38.71- -14.57, p<0.001); lower blood loss (OR, -92.84; 95% CI, -131.71- -53.97, p<0.001); lower additional surgical procedures (OR, 0.46; 95% CI, 0.31-0.69, p<0.001); and higher Oswestry Disability Index (OR, 1.49; 95% CI, 0.02-2.97, p=0.05) compared to autologous iliac crest bone graft. However, no significant difference was found between bone morphogenetic protein-2 and autologous iliac crest bone graft in non-union rates (OR, 0.34; 95% CI, 0.08-1.53, p<0.001); hospitalization days (OR, -0.21; 95% CI, -0.48-0.07, p=0.14); and adverse events (OR, 0.78; 95% CI, 0.52-1.16, p=0.22).

Conclusions:

Bone morphogenetic protein-2 significantly had a higher fusion rate, lower surgery time; lower blood loss, lower additional surgical procedures, and higher Oswestry Disability Index compared to autologous iliac crest bone graft. This relationship forces us to recommend bone morphogenetic protein-2 for the posterolateral fusion of the lumbar spine to avoid any possible negative postoperative results.