Midshaft clavicle fracture and acromioclavicular joint dislocation are common injuries in orthopedic traumatology. The diagnosis is relatively simple and clear clinically, and missed diagnosis is rare. However, the midshaft clavicle fracture with ipsilateral acromioclavicular joint dislocation is very rare in clinical practice. Once this kind of injury occurs, the failure to make a correct diagnosis of the dislocation of the ipsilateral acromioclavicular joint in time may cause the ipsilateral shoulder joint dysfunction and even medical disputes. Therefore, it is particularly important for the early diagnosis of midshaft clavicle fracture with ipsilateral acromioclavicular joint dislocation.

To discuss the diagnosis of midshaft clavicle fracture with ipsilateral acromioclavicular joint dislocation, and to provide reference for early diagnosis of this kind of injury.

Through the analysis of cases reported in domestic and foreign literatures, and retrospective analysis of the follow-up cases in our department, we conducted a study investigating age, gender, injury causes, and midshaft clavicle fracture with ipsilateral acromioclavicular joint dislocation.

A total of 19 English case reports of midshaft clavicle fracture with ipsilateral acromioclavicular joint dislocation and 7 Chinese document case reports were retrieved, including 22 cases with clear preoperative X-rays. In the meanwhile, we retrospectively analyzed 2 cases of this type injury during the clinical follow-up. Therefore, a total of 24 cases were included in the study. Among them, there were 16 males and 8 females. The ages ranged from 19 to 65 years old, with an average age was 37 years old. Most cases are caused by high-energy damages (21/24, 87.5%) . According to the classification of clavicle fracture, there were 19 cases (19/24, 79.2%) pf type A fractures, and 5 cases (5/24, 20.8%) of type B fractures. According to the classification of acromioclavicular joint dislocation, there were 12 cases of type IV (50.0%) , 6 cases of type III (25.0%) , 4 cases of type VI (16.7%) , and 2 cases of type V (8.3%) . There 9 cases (9/24, 37.5%) of combined injuries.

For relatively simple types of midshaft clavicle fractures caused by high-energy injuries, it is necessary to highly suspect whether there is ipsilateral acromioclavicular joint dislocation. The main points of diagnosis are as follows: (1) Inquire about the cause of injury in detail and understand the mechanism of injury; (2) For all cases of middle clavicle fractures, observe whether the acromioclavicular joint is swollen and subcutaneous bruising, and perform a physical examination of the acromioclavicular joint and coracoid process for tenderness. If there is tenderness, the acromioclavicular joint injury is highly suspected; (3) Carefully observe the changes of acromioclavicular joint gap and coracoclavicular gap on preoperative X-ray films. For instance, if the midshaft clavicle fracture is a relatively simple type and high-energy injury, high suspicion is required. It is recommended to take a control film as well as the CT examination of the affected shoulder joint; (4) After intraoperative fixation of the middle clavicle fracture, routine fluoroscopy of the ipsilateral acromioclavicular joint should be taken.