Comparing the Use of Nitinol Compression Screws to Traditional Compression Screws in Foot and Ankle Surgery

Abstract

Category: Hindfoot; Midfoot/Forefoot Introduction/Purpose: Nitinol is a metal alloy with high elastic flexibility and shape memory characteristics, making it effective in orthopedic surgery. Although nitinol staples have shown similar efficacy to traditional implants for foot and ankle surgery, the literature is limited regarding nitinol screws. The purpose of this study is to determine whether there is a difference in outcomes and complications between nitinol screws and traditional screws used for foot and ankle surgery. Methods: A multicenter retrospective cohort study was conducted for patients who underwent a foot and ankle procedure utilizing traditional compression screws or nitinol compression screws, between February 1st, 2021, and July 1st, 2023. Demographic factors, type of implant, and outcomes were recorded. Student’s t-test and Wilcoxon rank sum test were used to compare continuous variables, while the chi-squared test was used to compare categorical variables. Results: A total of 163 patients were included in the study, with 106 patients treated with traditional screws and 58 treated with nitinol screws. There was no significant difference between those treated with nitinol screws and those treated with traditional screws in complication rate (8.6% vs 11.3%, P=0.78), non-union rate (5.2% vs 8.5%, P=0.54), revision surgeries (1.7% vs 2.8%, P=1), hardware removal (3.4% vs 11.3%, P=0.14), or 90-day hospital readmissions (0% vs 2.8%, P=0.55) for foot and ankle surgery. Conclusion: Our study found no difference in terms of complications or postoperative outcomes between those treated with nitinol screws and those treated with traditional screws for elective foot and ankle procedures. Our findings suggest that nitinol screws appear to be safe and effective for foot and ankle surgery with positive postoperative outcomes and a trend in lower complication and non-union rates. However further investigation is warranted to assess if faster time to union and quicker weight bearing may be possible with this type of fixation.