Shoulder joint popping may be physiologic, or it may be caused by habitual dislocation of the shoulder joint, shoulder laxity, rotator cuff injury, glenoid labrum injury of the shoulder joint and other factors. 1. Habitual dislocation of the shoulder joint: The humeral head may frequently move in and out of the glenohumeral joint along the shoulder capsule tear when the shoulder joint is dislocated, resulting in wear and tear of the humeral head and the glenoid, and popping of the shoulder joint. 2. Shoulder laxity: When the shoulder capsule is lax, the humeral head may not be stable enough, causing the humeral head to collide with the glenoid, resulting in shoulder popping. 3. Rotator cuff injury: If there is violent pulling injury, it will easily lead to rotator cuff injury and shoulder popping phenomenon. 4. Shoulder labral injury: When the labrum of the shoulder joint is injured, the humeral head and the labrum of the shoulder joint collide, which may lead to shoulder popping. Shoulder popping may also be physiologic, which is caused by the rupture of gas compression in the joint cavity, and is usually not combined with discomfort. If it is combined with discomfort, one should go to a regular hospital for consultation, clarify the cause of the disease and follow the doctor’s instructions to avoid delaying the disease.