Limited Evidence for Biological Adjuvants in Hindfoot Arthrodesis A Systematic Review and Meta-Analysis of Clinical Comparative Studies

Background: The purpose of the present study was to evaluate the efficacy of biological adjuvants in patients managed with hindfoot arthrodesis. Methods: A systematic review of the PubMed and Embase databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines with use of specific search terms and eligibility criteria. Assessment of evidence was threefold: level of evidence by criteria as described in The Journal of Bone & Joint Surgery, quality of evidence according to the Newcastle-Ottawa scale, and conflicts of interest. Meta-analysis was performed with fixed-effects models for studies of low heterogeneity (I-2 < 25%) and with random-effects models for studies of moderate to high heterogeneity (I-2 >= 25%). Results: A total of 1,579 hindfeet were recruited across all studies, and 1,527 hindfeet were recorded as having completed treatment and follow-up visits. The duration of follow-up ranged from 2.8 to 43 months. Twelve of the 17 included studies comprised patients with comorbidities associated with reduced healing capacity. Based on the random-effects model for nonunion rates for autograft versus allograft, the risk ratio was 0.82 (95% CI, 0.13 to 5.21; I-2 = 56%; p = 0.83) in favor of lower nonunion rates for autograft. Based on the random-effects model for rhPDGF/beta-TCP versus autograft, the risk ratio was 0.90 (95% CI, 0.74 to 1.10; I-2 = 59%; p = 0.30) in favor of lower nonunion rates for rhPDGF/beta-TCP. Conclusions: There is a lack of data to support the meaningful use of biological adjuvants as compared with autograft/allograft for hindfoot arthrodesis. The meta-analysis favored the use of autograft when compared with allograft but favored rhPDGF/beta-TCP when compared with autograft in the short term.