Changes in lengths of the wrist ligaments during wrist radioulnar deviation: an in vivo study

Abstract

Objective To investigate changes in lengths of the wrist ligaments during wrist radioulnar deviation. Methods Six volunteers were included in the study. CT scans was used to detect the changes under different positions of the wrist in the volunteers. The wrists were scanned from the position of radial deviation of 20° to the one of ulnar deviation of 40° at an interval of 20°. The 3-dimensional carpal and distal radioulnar joint structures were reconstructed with customized software and chauges in length of the palmar and dorsal wrist ligaments in radioulnar deviation were computed. Results From wrist radial deviation to neutral position, the lengths of the radioscaphocapitate ligament, the long radiolunate ligament and the dorsal intercarpal ligament increased significantly (P ＜ 0.05), they increased (2.4±0.3) mm, (2.3±0.8) mm,(1.2±0.6) mm, (1.2±1.2)mm and (2.6±1.0) mm respectively. While from wrist ulnar deviation to neutral position, ulnocapitate ligament and the dorsal radiocarpal ligament increased significantly (P ＜ 0.05), they increased (0.8 ±0.6) nm and (1.0±0.5) mm respectively. Conclusion At wrist radial deviation, the radioscaphocapitate, long radiolunate and dorsal intercarpal ligaments are slack. At wrist ulnar deviation, the ulnocapitate ligament and the dorsal radiocarpal ligament are slack. These positions may be favorable to healing of these ligaments. Key words: Wrist; Ligaments; Tomography, X-ray computed