Reaming for Tibiotalocalcaneal (TTC) Nailing Removes Only 10% of the Ankle and Subtalar Joints

Abstract

OBJECTIVES: Tibiotalocalcaneal (TTC) nailing in the setting of acute ankle trauma has become increasingly popular. No consensus exists as to whether formal joint preparation is necessary, although there is some concern that residual motion at unprepared joints may lead to implant loosening and/or breakage. The objective of this study was to quantify the proportion of tibiotalar and subtalar articular surface destruction that occurs during reaming for TTC nail fixation. METHODS: Twelve cadaver lower extremities were procured. The specimens were pinned into neutral ankle and hindfoot alignment. A guide wire was inserted under fluoroscopy, followed by a 12 millimeter opening reamer. The specimens were then dissected, exposing the tibial plafond, talar dome, posterior facet of the talus, and posterior facet of the calcaneus. Images of each joint were obtained and ImageJ software was used to calculate the total joint surface area and the area of articular destruction. RESULTS: The mean proportion of articular cartilage destruction was 9.3%, 10.3%, 8.9%, and 10.3% for the tibial plafond, talar dome, posterior facets of the talus and calcaneus, respectively. No joint destruction was observed in the middle facets of the subtalar joint. CONCLUSIONS: Reaming for TTC nail placement violates approximately 10% of each articular surface of the tibiotalar and subtalar joints. Retention of 90% of the articular surface may allow for residual motion at the joints, and therefore, potentially substantial stress on the implant. Formal joint preparation for the purposes of achieving fusion during TTC nail placement may be beneficial to prevent implant loosening or breakage.