Comparison of Tibiotalocalcaneal Arthrodeses Using a Sustained Dynamic Compression Nail Versus Nondynamized Nails

Background. Tibiotalocalcaneal (TTC) arthrodesis is a common treatment option for hindfoot arthritis and deformity. Loss of compression over time with statically locked nails may contribute to nonunion. A novel retrograde intramedullary nail with an internal pseudoelastic component has recently been used to provide sustained dynamic compression (SDC). The purpose of this study was to compare fusion rates and time to union between the SDC and nondynamized (ND) nails. Methods. All patients who underwent TTC arthrodesis with an intramedullary nail at a single institution from 2013 to 2017 and who had at least 1 year of follow-up were included in this study. Baseline patient and operative characteristics were collected and compared between the sustained SDC and ND nail groups. The rate of successful fusion, time to union, and complications were compared between the groups. Results. The SDC cohort had a significantly faster time to union by 3.9 months (P = .049). The SDC cohort had a higher fusion rate (78.0%) compared with the ND nail cohort (75.0%), although this was not statistically significant (P = .75). The SDC nail was used significantly (P < .05) more often in patients with known risk factors for nonunion, including female sex, smoking, revision surgery, prior trauma, and patients requiring 3D cage implants for significant bone loss. There were no differences between the groups in terms of complications. Conclusion. The SDC nail has been shown to achieve successful arthrodesis in a population at high risk for nonunion, using less hardware, and at a faster rate than ND nails. Level of Evidence: Level III: Retrospective, comparative study.