This study evaluated the clinical and radiological outcomes of unstable distal clavicular fractures treated with an AO Hook plate.

From March 2009 to October 2010, sixteen patients with distal clavicular fractures underwent open plating using an AO Hook plate. The clinical outcomes were assessed by measuring the UCLA scores and KSS sores, and the radiological outcomes were evaluated using simple radiographs at the final follow-up.

Fracture union was obtained in all patients at an average of 13.9 weeks (range, 9~20 weeks). The UCLA scoring system showed excellent results in 9 cases and good results in 7. The average KSS scores of distal clavicular fractures were 95.5. At the final follow-up, subacromial osteolysis developed in 11 cases (68.7%) of whom 3 suffered from pain around the acromion. Other complications occurred in 4 patients: one had a fracture adjacent to the plate proximally, two had a stiff shoulder with subacromial impingement, and one had hypoesthesia around the surgical wound.

Unstable distal clavicular fractures treated with a Hook plate provided rigid fixation and satisfactory outcomes considering the high union rate. Nevertheless, potential postoperative complications related to morphometric properties of the plate should be considered.