Scapholunate interosseous ligament sectioning adversely affects excursions of radial wrist extensor and flexor tendons.

Excursions of tendons around the scaphoid were measured in 6 fresh cadaver forearms to evaluate the role of the scapholunate interosseous ligament (SLIL) in wrist joint motion. Excursions of the extensor carpi radialis longus (ECRL) and brevis (ECRB) tendons and the flexor carpi radialis (FCR) tendon were continuously recorded during wrist flexion, extension, and radial and ulnar deviation. Tendon excursions were measured in the intact wrists and after complete sectioning of the SLIL. Tendon excursions were altered significantly in the major ranges of wrist motion after SLIL sectioning. After ligament sectioning, excursions of the ECRL and ECRB tendons increased significantly in wrist flexion and extension. Excursions of the FCR tendon increased significantly during wrist extension and ulnar deviation. These findings support the concepts that integrity of the SLIL plays an important role in wrist function and that injury of the ligament may cause clinical problems.