Comparing Intraoperative and Postoperative Complications of Shape-Memory Nitinol Staples for Arthrodesis Across the Midfoot and Hindfoot

Category: Midfoot/Forefoot; Hindfoot Introduction/Purpose: Shape-memory nitinol staples are an increasingly common construct used for arthrodesis of the foot. In evaluating this new construct, a comprehensive understanding of the various complications associated with staple arthrodesis is necessary in addition to overall fusion outcomes. Therefore, the purpose of this study is to analyze complications associated with staple arthrodesis across the midfoot and hindfoot to determine if any differences exist in the rate of complications between these two joint complexes. Methods: This IRB approved retrospective cohort study examined patients from a single institution who underwent midfoot or hindfoot arthrodesis between 2013 and 2023. Inclusion criteria mandated postoperative CT scans for fusion assessment, excluding those without scans or lost to follow-up. Complications of interest were non-union requiring revision, infection, symptomatic hardware removal, and DVT occurrence. Statistical analysis was performed with ANOVA and t-tests using Python 3.11.7 and Microsoft Excel. Results: A total of 29 patients underwent arthrodesis across 39 joints in the midfoot while 31 patients underwent arthrodesis across 60 joints in the hindfoot with either staples alone or staples and screws. There was no significant difference in the rate of overall complications between joints fused with staples in the midfoot (9.5%) as compared to the hindfoot (11.1%). Likewise, there was no significant difference in complication rates for joints fused with screws and staples between the midfoot (33.3%) and hindfoot (24.2%). There was no significant difference in rates of staple mechanical failure, with staples breaking at similar rates in both the midfoot (10.3%) and hindfoot (8.3%). Conclusion: The complication rate of isolated staples as a fixation construct does not differ significantly between the midfoot and the hindfoot. The same is true of joint staple and screw constructs. However, overall rates of complications are high for joint staple and screw constructs, warranting further investigation with larger datasets.