ABSTRACT
In this study, we investigated the relationship of an osteoarthritis of the knee (OA) and a knee pain of single-leg on the bilateral difference of ground reaction force in stepping. The subjects were 29 middle-aged women (mean age 63.7±6.7 years). We categorized them into groups based on the following conditions: osteoarthritis of the knee (OA groups; n = 9), knee pain (KP groups; n = 7), and no pain (NP groups; n = 13). We measured the ground reaction force in a vertical direction when stepping on a platform. The evaluation variables were as follows: peak of ground reaction force at the early stance phase (F1), middle phase (F2), and late phase (F3). We calculated the bilateral difference of ground reaction force of the left and right leg and the affected side and the unaffected side ratio. The result of two way ANOVA, there was a significant difference between the leg in F1 and F3 and the group at F2. The result of comparison between the OA groups and the KP groups, there was no significant difference in the unaffected side and the affected side ratio, those in the OA groups tended to have a load on the unaffected side, while those in the KP groups had a load on the affected side. Therefore, it was suggested that there was the relationship of the OA and a knee pain of single-leg on the bilateral difference of ground reaction force in stepping.