Fig. 1

Model used to analyze kinematic data. Joint coordinate systems are presented for the trunk-global, humerothoracic, and elbow joints. Wrist and hand joints are not presented here for clarity. The transformation orders (degrees of freedom, DoF) are presented for each joint. Transformations written in bold characters and presented with their name in the table represent the degrees of freedom reported in the “Results” section. Note that elbow pronation-supination (Ry) occurs at the radioulnar (ru) joint. T, translation; R, rotation