The Use of Autologous Bone Graft vs Allograft Viable Cell Matrix in Forefoot, Midfoot, and Hindfoot Fusion

Submission Type: Other Research Type: Level 3 - Retrospective cohort study, Case-control study, Meta-analysis of Level 3 studies Introduction/Purpose: The use of autograft is considered the gold standard for improving the fusion rate in foot and ankle surgeries. Allograft may be useful as an alternative to autograft given its high accessibility and lack of harvesting complications. Newer generation allograft mixtures containing osteoconductive, osteoinductive and osteogenic factors which may have similar or even higher rates of success compared to older generations of allograft. The current study pursued comparisons of the rate of fusions, complications, and improvement in patient reported outcomes for patients treated with newer generation allograft mixtures, autograft, or a combination of allograft and autograft for forefoot, midfoot, and hindfoot fusions. Methods: A retrospective review was performed on patients who underwent forefoot, midfoot, or hindfoot arthrodesis procedures between March 2021 and May 2023 at a single academic institution. Allografts utilized included: Augment® (Wright Medical Group) with Bio4TM (Stryker) and Vivigen® (DePuy Synthes). A total of 208 joints in 140 patients were included in the study. 105 joints in 71 patients were treated with allograft, 29 joints in 19 patients were treated with autograft, 74 joints in 50 patients were treated with both autograft and allograft. Demographic information, graft specifications, and postoperative outcomes were collected. Categorical and continuous data were compared using Chi-squared test and analysis of variance (ANOVA), respectively. Paired t-tests were utilized to compare preoperative and postoperative Patient Reported Outcome Measurement Information System (PROMIS) scores. All p< 0.05 were considered statistically significant. Results: There were no significant differences between those treated with allograft, autograft, or both grafts in terms of fusion (97.14% vs 89.66% vs 90.54%, respectively), or readmissions (2.86% vs 0.00% vs 1.35%). Chi-squared revealed the incidence of revision surgery was statistically lower in cases where allograft was used alone (0% allograft vs 10.34% autograft vs 9.46% both, p< 0.001). PROMIS pain scores were improved in the allograft (∆-5.41± 9.62, p< 0.001), autograft (∆-10.41 ± 18.46, p=0.010), and allograft + autograft groups (∆-6.63 ± 11.45, p< 0.001). However, only patients treated with allograft or allograft + autograft demonstrated statistical improvement in PROMIS function (∆2.97 ± 9.63, ∆4.57 ± 7.88, p< 0.010) or mobility scores (∆4.57 ± 7.88, ∆3.05 ± 8.36, p< 0.001) at postoperative follow-up (Table 1). Conclusion: In patients undergoing forefoot, midfoot, and hindfoot arthrodesis procedures, superior outcomes and fewer revision surgeries were observed in those who received newer generation allograft in comparison to autograft alone. These results suggest newer-generation allografts may be used as an alternative to autograft in carefully selected patients. Data from the current study suggests these allografting strategies are as effective, if not more effective than autograft in promoting fusion during foot and ankle arthrodesis procedures. Longer duration, randomized studies, and cost analysis may be warranted to effectively expand on these findings.