Abstract
Diagnosis of anterior cruciate ligament (ACL) using body-mounted sensor is discussed. A wide variety of diagnosis method such as pivot shift test, lachman test and monitoring of jump motion are applied to examine the injured ACL. These methods, however, depend on the ability and the experience of examiner. The proposed method numerically provides the three dimensional translation and rotation of the knee by using a newly developed 3D sensor. The 3D sensor is composed of three accelerometers and three gyroscopes. Measured acceleration of the knee during the examination is converted to the fixed system of coordinate according the acceleration of gravity and 3D rotation of the sensor, and is numerically integrated to derive 3D trajectory and rotation angle around the tibia. The experimental results of jump test and pivot shift test show that the rotation angle of the tibia estimated from the 3D sensor provides unusual movement that suggests subluxation of injured ACL.
