Grade II acromioclavicular joint dislocation, or acromioclavicular joint dislocation, is still more serious. Most of the acromioclavicular joint dislocations are caused by direct violence, and are generally categorized into Grade I, Grade II, and Grade III according to the degree of injury. Grade II acromioclavicular joint dislocation is more serious in terms of injury, and rupture of acromioclavicular ligament and joint capsule may occur, but the rostral clavicular ligament is not damaged, and the joint is in the state of semi-dislocation. Patients often present with pain in the shoulder, localized augmentation, and limited shoulder motion. Grade II acromioclavicular joint dislocation is more serious and is mostly treated conservatively, such as closed reset, physical therapy, and external fixation. Immobilization after reset can compress the outer end of the clavicle downward, so that the upper arm and scapula upward, thus maintaining the acromioclavicular joint in a reset state. If the diagnosis of Grade II acromioclavicular joint dislocation is confirmed, it is recommended to seek medical treatment as soon as possible and standardize the treatment under the guidance of the doctor.