Fig 7. Average motion in degrees at the radioulnar joint coordinate system (JCS) for a R. norvegicus step cycle.

Above the graph is a representation of the forelimb posture relative to the step cycle. Here, all ten trials from all three rats were binned for every 5% of the step cycle. Radius long axis rotation (LAR, pronation) is shown in cranial view from the perspective of the ulna (the ulna appears to be stationary in these figures compared to the humerus and radius). Note the close synchrony between elbow flexion (Fig 7) and radius LAR. Given the small rotational movements at the Z- and Y-axes for the radioulnar JCS, only the X-axis rotations are shown. Red = X-axis (radius LAR relative to the ulna).