Rate of Subtalar Joint Arthrodesis After Retrograde Tibiotalocalcaneal Arthrodesis With Intramedullary Nail Fixation: Evaluation of the RAIN Database.

BACKGROUND: Hindfoot arthritis or significant deformity involving the ankle and subtalar joint (STJ) is a disabling condition with few salvage options. Many surgeons note a decreased STJ fusion rate compared with ankle union when a retrograde nail construct is used. The purpose of this study was to report the STJ fusion rate of tibiotalocalcaneal (TTC) arthrodesis with retrograde nail.

METHODS: A chart and radiographic review was performed. TTC fusions performed in patients with osteoarthritis, posttraumatic arthritis, or deformity correction with retrograde nail fixation were included. Exclusion criteria included neuropathy, Charcot arthropathy, and failed total ankle replacement.

RESULTS: Ultimately, 66 retrograde TTC fusions (in 63 patients) met inclusion criteria. The average age was 57.0 years. There were 29 female and 34 male patients. Radiographic fusion of the ankle and STJ was demonstrated in 68.2% of the patients. There were 11 cases (16.7%) of ankle arthrodesis with STJ nonunion, 6 cases (9.1%) of STJ fusion but ankle nonunion, and 4 cases (6.1%) of stable radiographic nonunion of both joints. The mean time to subtalar fusion was 112.1 days. One patient required revision surgery and conversion to below-knee amputation. One patient required a CROW walker for assistance with gait.

CONCLUSION: A 22.8% radiographic nonunion rate of the STJ was noted in retrograde TTC fusion. Despite this, patients were stable and pain free.

LEVELS OF EVIDENCE: Level IV: Retrospective Case series.