Ankle/hindfoot arthrodesis in rheumatoid arthritis improves kinematics and kinetics of the knee and hip: a prospective gait analysis study

Abstract

OBJECTIVES: To evaluate the effects of ankle/hindfoot arthrodesis in rheumatoid arthritis (RA) patients on gait pattern of the knee and hip. METHODS: In this prospective follow-up study, 14 RA patients scheduled for ankle/hindfoot arthrodesis (talo-calcaneal, talo-navicular, calcaneo-cuboid and/or talo-crural joints) and 14 age- and sex-matched healthy controls were included. Three-dimensional gait analyses of joint angles, moments and work were performed at the index operation and after 13 months of follow-up. Each patient underwent clinical assessments of pain while walking, overall evaluation of disease activity, Health Related Quality of Life Questionnaire (EQ-5D), activity limitations, maximum walking distance, difficulty with walking surface and gait abnormality. For comparisons of pre- vs post-operative conditions, Wilcoxon's matched pairs test and Friedman ANOVA by rank test were used. RESULTS: At follow-up after ankle/hindfoot fusion surgery, RA patients demonstrated a statistically significant improvement in mean range of joint motions, moments and work in the overlying joints such as the knee and hip. Moreover, there was significantly less pain, disease activity, activity limitation, difficulty with walking surface and gait abnormality. EQ-5D and maximum walking distance were also significantly improved at follow-up. CONCLUSIONS: Our results demonstrate that ankle/hindfoot arthrodesis in RA is an effective intervention to reduce pain and to improve Health Related Quality of Life and functional ability. Moreover, the overlying leg joints experience an improvement in joint motion, muscle-generated joint moments and work during walking. Three-dimensional gait analysis may assist future investigations of the effects of orthopaedic surgery on functional mobility in RA to prevent irreversible disablement.