Bilateral differences in gait mechanics following total ankle replacement: A two year longitudinal study

Background: Following total ankle replacement (TAR) patients demonstrate improvements in gait. The purpose of this study was to assess the changes in gait symmetry from a pre-operative assessment through two years following TAR. Methods: Seventy-eight patients who received a primary TAR and had no contralateral pain were examined. Three-dimensional joint mechanics and ground reaction forces were collected during seven walking trials preoperatively, and 1 and 2-years post-operatively. Data was analyzed using a 2 x 3 repeated measures ANOVA to determine significant differences between limbs and across time points (alpha = 0.05). Findings: Walking speed improved from pre-operative to each post-operative time point (P<.001; ES = 1.5). Peak dorsiflexion was not changed across time or between sides, however, the dorsiflexion angle at heel strike was increased on the nonsurgical side (P = 0.049; ES = 0.32). Peak plantar flexion moment (P<.001; ES = .80), stance (P<.001; ES = .29) and step time (P<.001; ES = .41) were improved from pre-op to 1 year post-surgery on the surgical side. Step (P<.001; ES = 1.2) and stride length (P<.001; ES = 1.2) demonstrated improvements across all time points, while the weight acceptance (P<.001; ES = 27) and propulsion ground reaction forces (P<.001; ES = .22) showed improvements between pre-op and 1 year post-op. Interpretation: The results of the study indicate that the patients are able to walk faster and demonstrate an improvement in gait symmetry; however, this improvement does not return the patient to a symmetric walking pattern by 2 years post-TAR. (C) 2014 Elsevier Ltd. All rights reserved.