Acromioclavicular joint dislocation is a common disease in shoulder surgery, which mostly occurs in young and middle-aged patients. Severe acromioclavicular joint dislocations of Rockwood type IV, V, and VI require surgical treatment. Among them, the common clinical type IV and type V severe acromioclavicular joint dislocations are often treated with autologous/allogenous tendon transplantation and coracoclavicular ligament reconstruction under shoulder arthroscopy. Although this minimally invasive surgical method has certain advantages over incision surgery, due to factors such as poor healing after tendon transplantation and failure of coracoclavicular fixation, the recurrence rate of postoperative dislocation is still as high as 30%, which seriously affects the prognosis of patients. Therefore, we proposed a new surgical technique of minimally invasive shoulder arthroscopic coracoclavicular suspension fixation and coracoclavicular ligament residual reconstruction, which aims to strengthen the fixation strength of the coracoclavicular space, promote the healing of the coracoclavicular ligament, and reduce the recurrence rate of postoperative dislocation. To improve postoperative shoulder joint function of patients. This project intends to use non-randomized controlled clinical research and biomechanical research to compare traditional surgical techniques with new microscopic techniques in terms of surgical efficacy, postoperative complications, and internal plant fixation strength to establish the therapeutic advantages of the new technology. Its application and promotion provide important clinical evidence to improve the treatment of severe acromioclavicular joint dislocation in the field of shoulder surgery.

Inclusion Criteria:

• Consecutive cases of coracoclavicular ligament reconstruction surgery usingTightRope Device With Allograft Augmentation and shoulder arthroscopic reconstruction of coracoclavicular ligament with autologous/allogeneic tendon transplantation.
• Injury type Rockwood type IV and V type severe acromioclavicular joint dislocation
• The time from injury to operation is less than 3 weeks

Exclusion Criteria:

• Combined with neurovascular injury
• Previous history of ipsilateral shoulder surgery
• The patient refused to sign the informed consent and participate in the trial