Effect of Tai Chi Exercise on Mechanical Joint Loading in Knee Osteoarthritis

Disabilities that arise from typical impairments of knee osteoarthritis (OA) include decreased muscle strength, reduced range of motion, and decreased aerobic cardiovascular function. A large number of individuals with knee OA experience disability and require rehabilitation. Traditional TC intervention has been a promising therapeutic intervention in knee OA, but the efficacy of TC as a knee OA intervention has proven inconclusive presumably because individuals with knee OA perform different TC components (steps) with widely varying mechanical knee joint loads. This variation could be a confounding factor in the way in which TC affects knee OA. Therefore, a feasibility study is proposed here to quantify external knee adduction moment (EKAM) response to the different TC steps, and then determine if it is feasible to use biofeedback of torque acting on the knee to modify some TC steps so as to reduce the EKAM they produce. Those TC steps whose EKAM can be easily reduced below mean EKAM during walking and those already below that level will constitute an optimized form of TC for knee OA; the remainder will be discarded. A phase 1 randomized controlled trial will be conducted to compare the optimized TC intervention to traditional TC training in reducing EKAM. The proposed research represents the first study to identify the biomechanical mechanisms of TC and to target EKAM by using a real-time biofeedback approach to manipulate EKAM during TC performance.