Midterm Outcome of Subtalar Joint Revision Arthrodesis

Background: The outcomes of revision subtalar arthrodesis have received relatively little focus in research compared with primary subtalar arthrodesis outcomes. This study aimed to assess the midterm clinical and radiologic results of subtalar joint revision arthrodesis and to analyze the risk factors that might influence the outcome of this procedure. Methods: We performed a retrospective review of 20 patients after subtalar joint revision arthrodesis for malunion, using interposition of iliac crest bone graft. The mean age was 55.75 years and the average follow-up lasted for 48.93 months. Eighty-five percent of the patients had at least 1 risk factor identified prior to revision. Patients' satisfaction and functional outcomes were evaluated with the American Orthopaedic Foot & Ankle Society Scale (AOFAS), the Foot and Ankle Outcome Score (FAOS), the Foot Function Index (FFI), and dynamic pedobarography. Results: A fusion rate of 80% was recorded whereas 20% of the cases ended with a painful pseudarthrosis requiring additional surgery. Pedobarographic measurements demonstrated that loading has a propensity toward the lateral column, but no substantial effect on the gait of patients. In this group, the following patient-reported outcomes were observed: 70% of the patients were satisfied, 20% of the patients found the result fair, and 10% were not satisfied with the results. Compared with the preoperative evaluation, postoperative functional scores showed significant improvement on the FOAS, AOFAS, and FFI outcome scales. Conclusion: Revision arthrodesis of the subtalar joint remains a challenging issue with a relatively high rate of nonunion, especially in a population of patients with multiple risk factors.