Crossed-Screw Configuration for Subtalar Arthrodesis: Clinical Outcomes of an Alternative Surgical Technique

BACKGROUND: Numerous fixation constructs have been described for primary subtalar arthrodesis with generally favorable union rates and patient outcomes. However, some techniques may pose technical challenges including difficult positioning, awkward instrumentation and screw trajectories, or difficulty in simultaneously manipulating subtalar alignment while inserting internal fixation, as well as issues associated with incisions on the posterior heel. An alternative crossed-screw construct reduces technical challenges, making simultaneous reduction and fixation of the arthrodesis easier and eliminating the need to insert screws from the posterior calcaneal tubercle, while achieving comparably high union and low complication rates in an easily learned technique. METHODS: A retrospective review was performed for patients who underwent subtalar arthrodesis between January 2017 and December 2022 at a single institution. Postoperative radiographs were screened for the crossed-screw construct in patients undergoing primary subtalar arthrodesis with diagnoses of primary subtalar arthritis, posttraumatic subtalar arthritis, postinfectious subtalar arthritis, hindfoot deformity correction, or talocalcaneal coalition. Postoperative data that were collected and analyzed included length of clinical and radiographic follow-up, radiographic union, symptomatic malunion, infection, symptomatic hardware, fracture, talar avascular necrosis, and secondary operative procedures. RESULTS: Average patient age was 51.5 years, and average radiographic follow-up was 26 months. Of the 99 subtalar crossed-screw arthrodesis procedures, radiographic union occurred in 96; 2 of the 3 patients with nonunion required reoperation. Three patients required revision for malunion, and 1 had deep infection requiring debridement. Five of the 7 patients with symptomatic lateral screws required removal. CONCLUSION: A crossed-screw subtalar arthrodesis construct provides successful outcomes with high union and low complication rates. Benefits of this alternative technique include ease of insertion, lower hardware removal rates than many reported constructs, avoidance of a posterior heel incision, reduced risk of penetration of the tibiotalar joint, and, as in this series, being associated with a high union rate and a low complication rate.