Preliminary study of 6 degrees of freedom measurement of scapula movement using a motion capture system

Summary form only given. The shoulder joint´s vulnerability to injury, especially while engaged in sports, makes it a frequent focus of the orthopedist´s attention. We investigated the mechanics of its motion, using a purpose-built camera setup able to detect, in six degrees of freedom, a set of round plastic markers attached to the skin, above bony landmarks. Since a given section of skin is able to slide in any direction, within a limited range, over the skeleton, the indicators deviate from their landmarks according to the degree of body movement. We established a set of landmarks that would lessen the influence of the skin´s mobility, in order to measure scapula movement accurately.