The main symptoms of acromioclavicular impingement are chronic dull pain, decreased strength and limited shoulder joint movement. 1. Chronic dull pain: due to the abnormal morphology of the lateral end of the acromion, formation of osteophytes, joint hypertrophy and other factors, the patient’s subacromial bursa and the surrounding tissues will have edema, hemorrhage, tear and other conditions, resulting in the persistence of the patient’s anterior chronic dull shoulder pain. 2. Decrease in strength: due to pain and complication of rotator cuff tear, it will cause decrease in strength of shoulder joint, and the patient will have more extensive rotator cuff tear due to the obvious weakening of muscle strength, and there is a tendency of continuous aggravation. 3. Restriction of shoulder joint activities: the patient’s pain is aggravated when the upper arm of the shoulder joint is abducted and lifted up, especially when the shoulder joint is abducted to 60 degrees to 120 degrees, which can be combined with the decline of internal rotation activity, so that the shoulder joint activities are severely restricted. If shoulder impingement is suspected, it is recommended to carry out regular treatment in time so as not to aggravate the adverse effects of the disease.