Repair of extensor pollicis longus using extensor pollicis brevis in rheumatoid arthritis.

In rheumatoid arthritis the commonest tendon to rupture in the hand is the extensor pollicis longus (Brewerton, 1957; Pulkki, 1961). It is particularly vulnerable, partly because it is a common site for marked proliferation of the synovium which can invade the tendon and partly because of its long course and sharp bend round Lister's tubercle which creates a point where attrition can occur (Backhouse and Kay, 1967; Vaughan-Jackson, 1962). This is illustrated by the fact that in the past 4 years forty repairs of extensor pollicis longus tendon have been required, while during the same period there have been only 23 repairs of the extensors digitorum; the majority of the latter involved extensor digiti minimi. In 1967 one of our patients presented with ruptures of extensor pollicis longus and the extensor tendons of the fourth and fifth fingers of the same hand. Extensor pollicis brevis was used to repair extensor pollicis longus, reserving extensor indicis proprius for the extensors of the fingers. Good function in the thumb and fingers was achieved. Since that time the tendon of extensor pollicis brevis has been used for repair of extensor pollicis longus. The reasons for this are: (1) It preserves extensor indicis proprius, which may be needed later to repair the finger extensors; (2) After this repair, extension of the thumb is in abduction rather than in adduction; (3) The operation is much easier to perform.