Assessment of stresses at the lower extremity joints wearing laterally wedged insoles

Laterally wedged insoles are known to be effective both in slowing the progression of knee osteoarthritis (OA) and in reducing pain at knee. Various research efforts have been made to investigate the effect of laterally wedged insoles on knee OA. However, most of the research works involved are either survey based or experimental, involving measuring knee alignments for the patients. In order to evaluate the effect of laterally wedged insoles more accurately, the internal stress distributions at the soft tissues of knee and ankle need to be known. A few works employ the finite element method to analyze the stress distribution at knee under a standing position but not for whole gait motion. In this study, the internal stress distributions at the soft tissues of knee and ankle during walking motion have been analyzed by employing an approach that integrate the finite element method with motion analysis. In this approach, the postures of finite element model are adjusted according to each phase of gait motion and the muscle forces obtained from motion analysis were applied as loading conditions to this FE model. Through this process, the effects of laterally wedged insoles on the lower extremity joints could be investigated by comparing the analysis results of normal gaits and gaits with laterally wedged insoles.