Acromioclavicular dislocation is a common shoulder injury in clinical joint surgery, accounting for about 2%-12% of all joint dislocations. The injury mechanism is mainly caused by violence on the acromion, resulting in the acromioclavicular ligament and coracoclavicular ligament injury through stress conduction. According to Rockwood classification widely used in the clinic, conservative treatment can be considered for type I and II acromioclavicular dislocations, and surgical treatment can be adopted for type IV, V, and VI. At the same time, there is still controversy in the clinical treatment of Rockwood type III acromioclavicular dislocation with coracoclavicular ligament and acromioclavicular ligament rupture. At present, studies have shown that Rockwood III acromioclavicular joint dislocation by adopting conservative treatment and internal fixation can obtain an excellent short-term curative effect. In contrast, conservative treatment can get short-term curative effects. However, with time and the movement of the shoulder joint, the possibility of further the acromioclavicular joint dislocation. For internal fixation of clavicular hook plate as the most commonly used internal fixation operation, removal of hook plate is often required 6 months after surgery. Whether the acromioclavicular joint is stable compared to the conservative treatment in the long-term curative effect comparison is unclear. Meanwhile, some foreign scholars believe that there is no sufficient evidence to prove that the therapeutic effect of clavicular hook plate is superior to non-surgical treatment. Objective To evaluate the mid and long-term clinical effects of conservative treatment and clavicular hook plate fixation in the treatment of Rockwood type III acromioclavicular dislocation and provide the basis for treatment options.

From September 2015 to September 2016, 72 patients with Rockwood type III acromioclavicular dislocation were retrospectively analyzed, and 47 patients were followed up. There were 23 patients treated with clavicular hook plate fixation (clavicular hook plate group) and 24 cases treated with conservative therapy (conservative treatment group) . The incidence of visual analog scale, shoulder function score, and complication rate between the two groups were compared at the 1st, 3rd, and 5th years after the operation.

The visual analog score of the 1-year follow-up group was slightly better than that of the conservative group, but there was no significant difference between the two groups (P>0.05) . The VAS scores of 3-year and 5-year clavicular hook plate groups were significantly higher than those of the conservative treatment group (P<0.05) , and the shoulder function score (Constant-Murley score) was significantly higher than that of the conservative treatment group. The VAS scores of the clavicular hook plate group in the 1st, 3rd, and 5th years were considerably better than those of the conservative treatment group (P<0.05) . The complication rate of the clavicular hook plate group was significantly lower than that of the conservative treatment group (P<0.05) .

Internal fixation with clavicular hook plate is an effective method for treating Rockwood type III acromioclavicular joint dislocation.