Abstract: A joint movement analysis system, comprising: a plurality of actual markers positioned around a joint, wherein space positions of the actual markers track space movement of virtual marker points that are set at anatomical bony landmark positions of the joint; an optical tracking device that senses the space positions of the actual markers so as to obtain a space movement data of the actual markers; a data collection device that collects the space movement data of the actual markers and a relative space position data of the virtual marker points with respect to the actual markers; and a data analyzing device that obtains a space movement data of the virtual marker points from the space movement data of the actual markers, and simulates and analyzes a movement of the bony structure of the joint according to the space movement data of the virtual marker points.

Abstract: A knee joint dynamic evaluation method for diagnosing human joint diseases by tracking motions of the knee joint includes constructing an evaluation model including a first angular difference threshold ?1, a second angular difference threshold ?2, and an anterior-posterior displacement difference threshold ?; synchronously collecting a single set of three-dimensional and six-degree-of-freedom movement data of a left knee joint and that of a right knee joint with devices; comparing the three-dimensional and six-degree-of-freedom movement data between the left and right knee joints with a data analyzing device, and calculating differences of the flexion and extension angles, the medial and lateral tilt angles, the medial and lateral rotation angles, and the anterior-posterior displacement movement values of the two sets of movement data; inputting the differences into the evaluation model to obtain the corresponding grading system, which will output the first, second, third, or fourth evaluation level.