The modified use of a proximal humeral locking plate for tibiotalocalcaneal arthrodesis

Background: Different types of fixation have been used to achieve a tibiotalocalcaneal (TTC) arthrodesis. The purpose of this study was to retrospectively examine the modified use of a 3.5-mm proximal humeral locking plate (PHILOS plate, Synthes, Paoli, PA) in obtaining a TTC fusion. Methods: Between April, 2003, and November, 2005, 17 patients had 18 TTC arthrodeses with a PHILOS plate through a trans-fibular approach. Preoperative diagnoses included Charcot arthropathy, neuromuscular disease, arthritis, and talar osteonecrosis. Patients were followed from 8 months to 3 years and 2 months (mean 20.6 months). Results: Fusion was achieved in 16 of the 17 patients (94.1%) and 17 of the 18 arthrodeses (94.4%) with a mean time to fusion of 20.6 weeks. The mean American Orthopaedic Foot and Ankle Society (AOFAS) score increased from 14.6 of 100 preoperatively to 76.7 of 86 (equivocal to 89.2 of 100) at final followup. One patient who had brittle diabetes went on to develop a nonunion. Conclusions: The patients in this study had a wide variety of medical conditions that left their bone osteopenic or osteoporotic. This study demonstrated that using a modified locking plate for a TTC arthrodesis results in a high rate of bony union and alignment correction stability. The locking plate provides fixation by acting as a fixed angle device, with the locking screws providing multiplanar fixation. The use of a locking plate has not been previously reported, and it may hold promise as a means of achieving a TTC fusion.