COMPLEX PALMAR DISLOCATION OF THE THUMB METACARPOPHALANGEAL JOINT - ACASE-REPORT DEMONSTRATING PARADOXICAL FUNCTION OF THE EXTENSOR POLLICIS LONGUS

Thumb metacarpophalangeal (MCP) joint dislocations are infrequent inju ries, and palmar dislocations rarely occur. The following is a case re port of a complex palmar dislocation of the thumb MCP joint that demon strates the unique physical finding of paradoxical flexion of the MCP joint (and interphalangeal joint extension) in conjunction with the pa tient's active attempt to extend the MCP joint. This finding proved to be indicative of extensor pollicis tendon displacement palmar to the MCP joint. This soft-tissue incarceration necessitated open reduction. A careful clinical examination is essential for an accurate evaluatio n of these injuries. Thus, a satisfactory clinical outcome can be atta ined with strict attention to the intraoperative pathology and techniq ue of repair.