Abstract
Using three-dimensional analysis, we measured the knee joint angle in walking for gonarthrosis patients and healthy elderly people and performed chaos analysis on the knee joint angle data of 3 gait cycles. In the comparison of the patients and healthy people using the Lyapunov index, which is a chaos index, the Knee OA group showed a significantly lower value compared with healthy elderly people (healthy elderly people: 1.90 ± 0.59, knee OA group: 1.61 ± 0.40, p<0.05). In correlation analysis of the Lyanupuv index of knee OA and clinical data (time from onset; the Japanese Orthopaedic Association knee joint function evaluation, JOA score; femorotibial joint, FTA; knee joint ROM, gait speed), a significant correlation was only obtained for the JOA score (r=0.73, p<0.05). These results show that the more serious the osteoarthritis was, the smaller the Lyapunov index became, suggesting this chaos index is related to the knee joint function.
