Fractures of the distal clavicle: outcomes and complications of surgical treatment using the hook plate

Aim. Distal clavicle fractures account for 15% of all clavicle fractures. Neer type II lateral end fractures are associated with non-union rates of 30%. Further, fixations by way of hook plates seem to have proved successful. We report our experience using the hook plate in the treatment of distal clavicle fractures. Methods. Twenty four patients with distal clavicle fractures were operated on and had an AO hook plate (Synthesi(R)) implanted. 20 men and 4 women were retrospectively reviewed. The average age at time of surgery was 35 (range 18-74). All the patients presented with a Neer type II distal fracture. The average follow-up was 20 months (range 10 - 26), and the patients were radiologically and clinically evaluated during this period of time. The Constant-Murley score was used to measure shoulder movement, strength and pain. The patient's ability to carry out his or her daily-life activities was measured with both the Constant-Murley score and the Oxford Test. Results. Twenty four patients achieved clinical and radiologic union and one patient suffered from failure of fixation. All the plates were removed. In the last visit, the mean Constant-Murley score and the mean Oxford score were 85 and 42, respectively, and seven patients presented with osteolysis. All patients were able to return to their preinjury activity level. Conclusion. Hook plate fixations of distal clavicle fractures offer good functional results with the shortcoming of plate removal after bone fusion is achieved. Osteolysis is a common complication associated with keeping the implant for over 6 months and it did not result in poor functional outcomes.