Clavicular hook plate for acute high-grade acromioclavicular dislocation involving Rockwood type V: clinical and radiological outcomes and complications evaluation

BACKGROUND: The surgical treatment of high-grade acromioclavicular joint dislocation remains a matter of debate. Clavicular hook plate internal fixation was widely used in the treatment of acromioclavicular dislocation because of its easy-to-master surgical technique. This study aimed to evaluate outcomes using hook plate fixation for acromioclavicular dislocation. METHODS: A consecutive series of 57 patients with acute acromioclavicular joint dislocation involving Rockwood type V were treated between November 2013 and September 2019 using hook plate fixation. The functional outcomes (using the visual analogue score, Constant-Murley score, and University of California Los Angeles score), the quality of surgical reduction (using the coracoclavicular distance), and post-operative complications were assessed with about 46 months of follow-up. RESULTS: The mean Constant-Murley score increased from 72.6 before surgery to 87.6 at final follow-up. The mean University of California Los Angeles score was 14.1 pre-operatively and 31.6 at final follow-up. Meanwhile, the visual analogue scores were significantly reduced from 3.4 pre-operatively to 1.3 post-operatively. The coracoclavicular distance decreased from 19.4 mm pre-operatively to 10.9 mm at the last follow-up. Post-operative functional and radiological outcomes were significantly improved compared with pre-operative outcomes (P < 0.01). The overall excellent and good result was 35.1% (20/57) and 54.1% (31/57), respectively. At follow-up, the overall complication rate was 15.8% (9/57) including subacromial impingement (three patients), acromial osteolysis (three patients), reduction loss (one patient), acromioclavicular joint osteoarthritis (one patient), and calcification (one patient). CONCLUSION: Hook plate fixation was a viable treatment approach, and achieved good clinical outcomes in the treatment of acute acromioclavicular dislocation involving V. But some complications of hook plate fixation should not be ignored.