Subtalar Arthrodesis in Patients With Avascular Necrosis of the Talus

Abstract

Category: Hindfoot Introduction/Purpose: Avascular necrosis (AVN) of the talus can lead to subtalar arthritis, pain, and decreased function. Isolated subtalar arthrodesis has been attempted in these patients, potentially allowing re-vascularization of the talus from calcaneal bone ingrowth while preserving the tibiotalar joint. The purpose of this study is to determine the union rate and complications of subtalar arthrodesis in patients with AVN of the talus. Methods: After obtaining IRB approval, a retrospective review of subtalar arthrodeses performed at a single academic institution, from 2000 to 2014, was conducted. Patients were included if they had a preoperative diagnosis of avascular necrosis of the talus, underwent subtalar arthrodesis and had a minimum follow up of 12 months. Exclusion criteria include: age younger of 18 years, incomplete clinical and radiological data or those whom underwent a concomitant tibiotalar arthrodesis. Results: Twelve patients with a mean age of 46.6 ± 13.9 years were included in the study. The fusion rate was 58% with a mean time to fuse of 35 weeks (range, 14-146). Seventeen percent of the patients had diabetes or vascular disease and an additional 17% had a positive history for tobacco use. The overall complication rate was 67% (8 patients). Five patients progressed to non-union (42%) and three of them underwent revision to tibiotalocalcaneal arthrodesis. Two patients (17%) had progression of AVN, one of which necessitated a tibiotalocalcaneal arthrodesis. Two patients (17%) developed a wound dehiscence that healed uneventfully with local wound care and oral antibiotics administration. One patient (8%) underwent hardware removal. Conclusion: With a fusion rate as low as 58% and a 67% complication rate, caution should be exhibited when considering an isolated subtalar arthrodesis in the setting of AVN of the talus. In selected cases, consideration should be given to extending the arthrodesis site to include the tibiotalar or talonavicular joint or revascularization procedures such as concomitant vascularized bone grafts.