Implant Choice and Outcomes of the Sinus Tarsi Approach for Displaced Intra-articular Calcaneal Fractures

Background: Operative fixation of displaced intra-articular calcaneal fractures is considered the gold standard, for which multiple fixation methods are available. This study compares the (functional) outcome of screw fixation (SF), plate fixation (PF), and anatomical plate fixation (APF) via the sinus tarsi approach (STA). Methods: A total of 239 patients (265 fractured calcanei) who received surgical treatment of a displaced intra-articular calcaneal fracture via STA between 2011 and 2022 were included. Results: Böhler angle (BA) measured immediately postoperatively (BA post-OR) and the decrease in BA at 1 year (∆BA) differed significantly in favor of PF/APF compared with SF (BA post-OR: SF vs PF P =.010 and SF vs APF P =.001; ∆BA: SF vs PF P =.032 and SF vs APF P =.042). Implant removal surgery was performed significantly less in the APF group as compared to the SF/PF groups (APF vs SF/PF; 9.9% vs 22.9%/23.7%, P =.015). Surgical site infections and secondary arthrodesis of the subtalar joint occurred equally in the 3 groups. Furthermore, the mean American Orthopaedic Foot & Ankle Society ankle-hindfoot scale, Foot Function Index score, and EuroQOL-5D-index / visual analog scale score, did not differ notably between SF, PF, and APF. Conclusion: The results show that both PF and APF are favored over SF because of an improved correction of BA measured directly postoperatively, a lower secondary loss of BA and, for APF, a lower implant removal rate. There was no difference in the rate of surgical site infections, need for secondary arthrodesis, nor functional outcome scores between different implants using the STA. Level of Evidence: Level III, retrospective cohort study.