A Non-invasive Method to Measure Joint Range of Motion for Hip Joints

In order to reduce the risk of dislocation after total hip arthroplasty, a hip joint range of motion should be evaluated properly. The non-invasive measuring method which obtains the joint range of motion without using computed tomography or X-ray is proposed in this research. A hip joint center inside a body is estimated by two positional sensors which are attached on a body surface. The joint range of motion is calculated by the estimated hip joint center and positions and orientations of the pelvis and the femur. The effectiveness of the proposed method is discussed.