Automatic rehabilitation of the Extension Lag using the developed knee assistive instrument

Patients with Extension Lag cannot extend their knee straightly single-handedly. However, they can extend their knee without pain, if the other (a physical therapist (PT)) stretch the knee. The recovery of the Extension Lag is not necessary surgery, and is often enough only to perform rehabilitation. However, the rehabilitation of the Extension Lag is hard work for the PTs. This paper proposes the control algorithm for the automatic rehabilitation of the Extension Lag by adapting the Knee Assistive Instruments for Rehabilitation (KAI-R) that has been developed for the walking rehabilitation after the surgery of the Total Knee Arthroplasty (TKA) in order to reduce the load of the PT. The safety and the effectiveness of the robot are necessary to be verified, because we are going to adopt the robot to a clinical trial. First, the validity of the motion of the robot that is installed the control algorithm is confirmed by the high speed movie camera. Secondly, the effectiveness is investigated by using surface myoelectric potential. Thirdly, the motion of the robot is confirmed by the doctor and the PTs. It is clear that the robot for the rehabilitation of the Extension Lag can be adopted to a clinical trial.