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

SLR - April 2022 - Tara McElroy

Reference: Dexter Seow, MBBCh, Youichi Yasui, MD, PhD, John F. Dankert, MD, PhD, Wataru Miyamoto, MD, James D.F. Calder, MD, PhD, FFSEM(UK), FRCS(Tr&Orth), and John G. Kennedy, MD, MCh, MMSc, FFSEM, FRCS(Orth). Limited Evidence for Biological Adjuvants in Hindfoot Arthrodesis: A Systematic Review and Meta-Analysis of Clinical Comparative Studies. The Journal of Bone and Joint Surgery. 2021, Sep; 103(103):1734-43.

Level of Evidence: Therapeutic Level IV

Scientific Literature Review

Reviewed By: Tara McElroy, DPM, MPH
Residency Program: Inova Fairfax Medical Campus – Falls Church, VA

Podiatric Relevance: With delayed and nonunion as potential complications for arthrodesis, biologic adjuvants have been incorporated into hindfoot arthrodesis procedures with the aim to augment biological potential for osseous integration at fusion sites. The purpose of this study was to evaluate the efficacy of biological adjuvants in aiding in fusion in hindfoot arthrodesis procedures.

Methods: Under PRISMA guidelines, a systematic review and meta-analysis was performed using PubMed and Embase databases, with search terms under three themes: biological adjuvants, hindfoot, and arthrodesis. Using peer-reviewed, comparative or single-arm prospective studies published in the English language, outcomes for union rate, time to union, bridging bone percentage, functional outcome scores, patient satisfaction rate, and complications, were recorded. Statistical analysis was performed using RevMan, with a p value of <0.05 for continuous and dichotomous outcomes.

Results: A total of 17 studies were included from the 1,761 studies under review, yielding a total of 1,579 hindfoot procedures with an average follow up ranging from 2.8 to 43 months. Four osteoconductive comparative studies, 12 cross comparative studies, and 1 single arm prospective study was included. In the osteoconductive grafts studies, time to union for autografts ranged from 3.5 to 11.3 months, compared to allografts which ranged from 3.9 to 13 months. In the cross comparative studies, the mean union rate was 60.7 percent in the autograft group compared to 71.5 percent in the recombinant human platelet-derived growth factor/β-tricalcium phosphate group. The single arm prospective study investigated cellular bone allografts, finding a union rate of 68.5 percent at six months.

Conclusions: There was no significant difference between autograft and allograft in terms of union rates, with results trending towards autografts having lower nonunion rate. Similarly, there was no difference in union rates between autograft and the rhPDGF/β-TCP phosphate arm, with results trending toward lower non-union rates for the rhPDG/B-tricalcium. The authors recommend continued use of autograft for hindfoot arthrodesis, as the current literature lacks regular and meaningful use of biological adjuvants, as seen in this study.