Abstract: A method for creating a frame of reference of a leg of a subject for subsequent 3-D kinematic analysis of the leg with non-invasive trackable references secured to the femur and the tibia of the leg. The method comprises the steps of: i) obtaining tibial and femoral axes with respect to the trackable references by tracking points and motions of the leg; ii) registering a known posture of the subject with respect to the trackable references; iii) obtaining a desired posture of the subject with respect to the trackable references as a function of the known posture by tracking a predetermined motion of the leg; and iv) setting a frame of reference to said tibial and femoral axes of the leg in the desired posture of the subject with respect to the trackable references.

Abstract: A harness for attachment about a knee femur and comprised of a rigid and non-flexible frame support two resiliently mounted clamping means and sensors is described for the non-invasive measurement of knee motion and its analysis in 3-D is described. The clamping means elements are urged under pressure outwardly for application against a skin outer surface at predetermined medial and lateral sites relative to a femur. A non-resilient adjustable stabilizing element is connected to the rigid frame and disposed at a predetermined location with respect to the medial clamping element in spaced relationship therewith and adjustable for clamping contact on a skin outer surface and in alignment with the center of a medial condyle of the femur whereby to stabilize the rigid frame about a knee. An attachment rod is secured to the harness and has straps for securing the rod above the knee.