Rupture of the extensor pollicis longus tendon.

Rupture of the extensor pollicis longus (EPL) tendon after nondisplaced fracture of the distal radius is a known complication, but can also occur in nonrheumatoid patients without a history of fracture. This study is a retrospective analysis of seven patients treated between 1985 and 1992. Five EPL ruptures occurred with nondisplaced Colles' fractures. Two involved a chronic tenosynovitis of the second dorsal extensor compartment of the wrist. The age of the patients ranged from 29 years to 68 years (mean, 42 years). Length of follow-up ranged from 6 weeks to 62 months (mean, 30 months). Rupture occurred at a median of 7 weeks (range, 2 weeks to 11 months) from the time of the distal radius fracture. Three extensor indicis proprius tendons and four free palmaris longus tendon grafts were performed. At final follow-up, six patients had an extensor lag < 10 degrees or normal thumb interphalangeal joint motion. One patient had a 25 degrees extensor lag. The causes of EPL rupture include mechanical irritation, attrition, and vascular impairment leading to delayed rupture. Synovitis of the extensor carpi radialis due to repetitive use may invade the EPL tendon and lead to rupture. Extensor indicis proprius transfer or free palmaris longus grafts yield good results after EPL rupture.