The pain of pressure on the bump of the acromion is considered to be caused by trauma, dislocation of the acromioclavicular joint, acromioclavicular impingement syndrome and so on. 1. Trauma: the first consideration is caused by trauma, which may be caused by localized violent impact, resulting in soft tissue injury in the acromion area, localized swelling and bulging, with symptoms such as pressure pain. 2. Dislocation of shoulder joint: shoulder joint is composed of humerus and scapula, when hit by external force, the bones and bones of shoulder joint are misaligned, and dislocation of shoulder joint can occur, and the phenomenon of shoulder bump occurs, accompanied by pain, swelling, deformity, and activity disorders. 3. Acromioclavicular Impingement Syndrome (AIS): The abnormal morphology of the acromion, osteophytes and other reasons lead to the narrowing of the distance between the acromion and the humeral head, which will lead to the extrusion and impingement of the subacromion structure, resulting in AIS, which can cause the phenomenon of acromion bulge, and is accompanied by the chronic dull pain in the front of the shoulder and the weakening of the muscle strength. Shoulder bump will be painful when pressed, it is recommended that patients go to the hospital in time for a detailed examination and targeted treatment according to the cause of the disease.