A systematic method of arthroscopic testing of extrinsic carpal ligaments: implication in carpal stability

Several biomechanical studies have shown that the scapholunate and lunotriquetral ligaments are not the only stabilizers of the proximal carpal row. However, no study has yet analyzed the spectrum of ligamentous lesions in vivo, leading to instability. We describe an arthroscopic technique for evaluating the extrinsic carpal ligaments. The testing relies on visualization and palpation of different ligaments. Their integrity is assessed with a 4-stage scale. Radiocarpal arthroscopy enables assessment of the following ligaments: the radiocarpal part of the radio-scapho-capitate, the long radiolunate, the short radiolunate, the ulnolunate, the ulnotriquetral, and the dorsal radiocarpal. Midcarpal arthroscopy enables assessment of the mid part of the radio-scapho-capitate, the triquetrocapitate, the scaphotrapezial, and the dorsal intercarpal. Above assessment is proposed in addition to assessing the articular cartilage, scapholunate, and lunotriquetral ligaments. This method allows a precise arthroscopic assessment of the extrinsic ligaments of the wrist. It could give an important help in the understanding of carpal instability.