[Pathophysiology of perilunate dislocation].

The anatomy of the palmar scapho-triquetral ligament was studied: on 15 hand specimens by means of gross anatomical dissections and MR imaging; and on a further 10 foetal wrist specimens, microanatomically. This ligament allows us to present the proximal carpal row as a socket, consisting of an upper part (the triquetrum, distal part of the scaphoid, and the dorsal and palmar scapho-triquetral ligament), and a base (the concave parts of the lunatum and scaphoid, connected by the scapho-lunate ligament). With a hyperextension wrist injury the upper part follows the distal part of the carpus, while the base remains fixed at the radius. The upper part slips away from the base, consequently, injuring the ligamentous structure, or causing a scaphoid fracture. The luno-triquetral and the palmar scapho-triquetral ligaments are also frequently torn. The overall prognosis depends on the grade of ligament damage. The arthroscopy allows us to estimate the state of the ligament structures, therefore, it is indicated before any reconstructive operation.