The Hysteresis Effect in Carpal Kinematics

The computation of the total hysteresis area from the hysteresis effect was found to be a sensitive technique to determine the subtle onset of abnormal carpal motion. By using this technique in a ligament sectioning study significant increases in the total hysteresis area were seen after just scapholunate interosseous ligament sectioning during wrist radioulnar deviation. This subtle change may signify the onset of dynamic scapholunate instability. The total hysteresis area of the lunate in a subset of lax specimens did not increase after ligament sectioning. This divergent behavior may explain why some patients with scapholunate instability do not develop dorsal intercalated segmental instability.