Outcome of avulsion fractures of the ulnar base of the proximal phalanx ofthe thumb treated nonsurgically

We report a retrospective study of avulsion fractures of the ulnar collater al ligament of the thumb metacarpophalangeal joint that were treated nonsur gically. The study included 30 patients who answered a questionnaire. None of the patients underwent surgery after treatment. The average follow-up in terval was 3.1 years (range, 1-5.2 years). All 30 patients were satisfied w ith the treatment and outcome. No patient had a permanent job change or ina bility to participate in recreational activities. Nineteen patients had no pain on motion of the thumb. Of the 20 patients (67%) who agreed to a follo w-up examination, key pinch and grip strength were not statistically differ ent between the injured and noninjured sides. Three patients had instabilit y on stress testing. There was a 25% nonunion rate. While not statistically significant, symptomatic patients tended to have slightly larger fragments (5.4 mm x 1.7 mm vs 3.2 mm x 1.4 mm on anterioposterior x-rays) and greate r initial rotation (26 degrees vs 24 degrees) of the fracture than asymptom atic patients. Despite the nonunion rate and the patients with clinical ins tability, all 30 patients were satisfied with their treatment. Copyright (C ) 1999 by the American Society for Surgery of the Hand.