Ankle-Hindfoot Reconstruction by Tibiotalocalcaneal (TTC) Arthrodesis Using Multiple Cannulated Screws: 32 Cases

CATEGORY: Ankle; Ankle Arthritis INTRODUCTION/PURPOSE: Tibiotalocalcaneal (TTC) arthrodesis is a salvage procedure that can be used as an alternative to amputation for various pathologic conditions of the ankle-hindfoot. The aim of this study is to evaluate the clinical-radiological outcome of TTC arthrodesis performed using the multiple cannulated screws. METHODS: From 2003 to 2018, 32 ankles (31 patients) underwent TTC arthrodesis. The mean follow-up period was mean 32.5 (12-92) months and the average patient age at surgery was 59.6 years (43-75). The etiologies of TTC arthrodesis included posttraumatic osteoarthritis (18.8%), Charcot arthropathy (18.8%), paralytic deformity (21.9%), failure of total ankle arthroplasty (9.4%), and failure of arthrodesis (9.4%). For all of 32 cases, transfibular approach was used with or without auto fibular cancellous bone graft. 7.3mm cannulated screws were used for fixation of arthodesis for all of 32 cases, and in 23 of 32 cases (71.9%), screw- fixation was used exclusively without any additional plate or Ilizarov fixator. Especially for 11 of 32 cases with large bony defect, fresh-frozen allo-femoral head structural bone graft was used. Pre- and postoperative visual analog scale (VAS) pain, the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot functional score, and radiographs including CT images were assessed. RESULTS: Overall union rate was 81.3% (26/32). Mean VAS score decreased from 6.92 preoperatively to 1.46 postoperatively and the AOFAS score improved from 27.0 to 53.7 (Max=68) at the final follow-up. Complication of TTC arthrodesis included nonunion (18.8%, 6/32), infection (12.5%, 4/32), and one case of skin necrosis. Most frequent nonunion site was tibiotalar joint (6/32). For 3 of 7 cases with nonunion, patients were painless and could ambulate without severe functional impairment. There were two cases with infective nonunion and one case with active Charcot arthropathy after artrhdesis. Union rate of two groups with/without allo-femoral head bone graft were similar to each other (81.8%, 81.0%, respectively), however, final AOFAS scores were significantly superior in 'without' femoral head bone graft group. CONCLUSION: This study achieved a fusion rate comparable to other previous studies and obtained favorable clinical outcomes. Realignment TTC arthrodesis using multiple cannulated screws is a valid surgical option as a salvage procedure for various deformed or arthritic conditions of ankle-hindfoot. Allo-femoral head structural bone graft can be selected as useful option for TTC arthrodesis with large bone defect.