The congenital trigger thumb: is release of the first annular pulley alone sufficient to resolve the triggering?

Abstract

The recognized treatment of persistent congenital trigger thumb (CTT) is surgical release of the flexor pollicis longus (FPL) tendon by transection of the first annular (A1) pulley at the thumb metacarpal head. Twenty-seven children with persistent CTT were operated between 2000 and 2004. The average age at surgery was 34 months. In 16 patients, the CTT appeared unilaterally and was the sole anomaly in the hand. The others suffered from either multiple hand abnormalities or another syndrome. In only 3 of the 16 thumbs (ie, 19%) division of just the A1 pulley at the metacarpal (MC) head was sufficient to relieve the triggering. In 11 thumbs (69%), a structure other than the sheath and distally from the A1 pulley, up to halfway the proximal phalangeal shaft (as a single entity), was discovered and had to be released also. A separate annular pulley, distal to the A1 pulley and other than the A2 pulley, was found in 2 cases (13%). In both cases, transection of this separate annular pulley alone sufficed. Complete release of the FPL was obtained in all, and none presented with postoperative complications at an average of 24 months' follow-up. Our clinical study suggests that a separate annular pulley system may exist, which has to be transected to allow for free FPL excursion in perhaps as many as 2 out of 3 CTTs. In our study group, this was not accompanied by complications.