Changes in Contact Pressure at the Lower Extremity Joint with an Unstable Shoe

Unstable shoes are known to increase muscle activities and change one’s gait pattern. However, the effect of unstable shoes on articular cartilages of lower extremity has not been studied. Since the changes in contact pressure applied to cartilage may destroy the cartilage matrix and cause arthritis, the effect of the gait pattern on the contact pressure at the lower extremity joint needs to be studied. The purpose of the present study is to evaluate the effect of wearing unstable shoes on contact pressure distribution of the cartilage of lower extremities by integrating motion analysis with finite element (FE) analysis. Among unstable shoe, Masai Barefoot Technology (MBT) shoe was considered as evaluation. Motion capture and gait analysis were performed and the results were applied to FE model as boundary and loading conditions. Finally, FE analysis was performed to simulate the biomechanical behavior of the knee and ankle cartilages according to the changes in gait patterns. Compared to normal shoes, MBT shoe decreased the maximum contact pressure of knee and ankle cartilages during a gait cycle.