Tibiotalocalcaneal Arthrodesis Using a Novel Retrograde Intramedullary Nail

Background. Tibiotalocalcaneal (TTC) arthrodesis is a common treatment option for complex hindfoot pathology. Overall union rates range from 50% to 86% but can be even lower in certain populations. A novel retrograde intramedullary nail has recently been developed. The purpose of this study was to report fusion rates, time to weight-bearing, and complications with the use of the A3 Fusion Nail. Methods. All patients 18 years or older who underwent TTC arthrodesis with an A3 Fusion Nail at a single institution from 2010 to 2015 with a minimum 3-month follow-up were included in this study. Rates of successful fusion, time to union, time to weight-bearing, and complications were evaluated. A total of 20 patients with an average age of 58.1 years and an average follow-up of 12.5 months met inclusion criteria. Results. Successful TTC arthrodesis was achieved in 14 of 20 patients (70%) overall. Average time to union was 8.1 months, and average time to weight-bearing was 6.8 weeks. Of 20 patients, 17 (85%) required femoral head allograft for bulk bone defects, and the union rate in this subset of patients was 76.5%. The rates of revision surgery (10%) and complications were low. Conclusion. The A3 Fusion Nail demonstrated a favorable safety profile and achieved TTC arthrodesis at a rate consistent with historical data despite being used in a patient population at high risk for nonunion. In patients with bulk bone defects at high risk for nonunion, the A3 Fusion Nail demonstrated superior rates of fusion (76.5%) to those reported in the literature (50%).Level of Evidence: Level III: Retrospective cohort study.