Rj. Alioto et Vd. Pellegrini, COMPLEX PALMAR DISLOCATION OF THE THUMB METACARPOPHALANGEAL JOINT - ACASE-REPORT DEMONSTRATING PARADOXICAL FUNCTION OF THE EXTENSOR POLLICIS LONGUS, Clinical orthopaedics and related research, (296), 1993, pp. 118-121
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.