Evaluation of the Influence of a New Design of Orthosis on the Loads Applied On the Knee Joint

Abstract

Background: Knee osteoarthritis influences the ability of the subjects during standing and walking. Although knee offloading orthosis reduces the loads applied on the knee joint and decrease knee pain, most of the subjects discontinue brace use due to stretching the ligaments structure of the knee joints, and tendency of the brace to migrate distally. Therefore, a new type of orthosis was developed to overcome the aforementioned problem. The aim of this research was to check the influence of this orthosis on reducing the loads applied on the knee joint. Method: A group of normal subjects was recruited in this study to walk with and without the orthosis. A Kistler force plate and Qualisys motion analysis system were used to collect the kinetic and kinematic parameters. The difference between walking parameters under two conditions was evaluated by paired t test. The p-value of difference was set at 0.05. Results: There was no difference between spatiotemporal gait parameters during walking with and without the orthosis (P-value>0.05). The adductor moment applied on the knee joint was 0.433±0.138 and 0.478±0.143 N.m/BW while walking with and without the orthosis, respectively (P-value=0.006). There was a slight increase in the hip adductor moment while walking with orthosis. Conclusion: The new design of the orthosis reduces the loads applied on the knee joint through the hip joint. The new orthosis decreases the loads applied on the knee joint without any negative influences on the walking performance.