Long-term outcomes after phalangeal distraction lengthening in patients with constriction band syndrome

Abstract

We investigated the long-term post-operative outcomes, more than 10 years after surgery, of distraction lengthening of phalanges in patients with congenital constriction band syndrome. Five shortened digits of two patients with congenital constriction band syndrome underwent distraction lengthening of the proximal phalanges using external fixator for the reconstruction of grasp and pinch at age of 53 and 41 months. The post-operative followed-up was 126 and 124 months. Subjective evaluation of hand function was performed using the tape measure method and Functional Dexterity Test pre-operatively and at 1 year after surgery. The parameters for proximal phalangeal distraction and the changes in the length ratio of the phalanges were evaluated. Grasp and pinch function was markedly improved after phalangeal lengthening. Regarding the radiographic findings, the length of distraction was 9.7 mm, % increase of lengthening: 52%, duration of distraction: 28 days, duration of fixation: 83 days, and healing index: 90 days. At the latest follow-up, the relative length of the proximal phalanx did not change significantly (−6%) during the 10 years after distraction lengthening. Patients with constriction band syndrome obtained favorable hand function and preserved those functions for more than 10 years after distraction lengthening of short phalanges using an external fixator.