Traumatic and spontaneous dislocation of extensor tendon of the long finger.

Extensor tendon dislocation is an unusual problem in patients unaffected by rheumatoid arthritis. Sixteen cases of ulnar dislocation of the long extensor tendon of the long finger are reported. Five of these cases were classified as traumatic dislocation and 11 as spontaneous dislocation. All cases were treated by surgery. Differences in anatomic and clinical features between traumatic and spontaneous dislocation of the long extensor tendon are described.