Middle-aged and elderly people often suffer from shoulder pain. In addition to localized spontaneous pain, they have difficulties in raising their arms to comb their hair or scratching their backs, putting on and taking off their clothes, taking a shower, etc. They may also wake up with shoulder pain when they turn over during sleep; sometimes, they may feel numbness in their arms or even weakness in their hands. They always think this is a common “frozen shoulder”. Some people with shoulder pain do not seek medical help, but only exercise or massage on their own, resulting in a delayed deterioration of their condition, and then they conclude that “frozen shoulder is not treatable”. Are there really that many people suffering from frozen shoulder? In fact, most of the causes of shoulder pain are not frozen shoulder. There are many causes of shoulder pain, so here are some of the main causes for your reference: Rotator Cuff Disorders Rotator cuff disorders are the most common cause of shoulder pain, with an incidence rate of 60%, much higher than frozen shoulder. The rotator cuff is formed by the four tendons of the supraspinatus, infraspinatus, subscapularis and teres minor, which link the humerus (upper arm) to the scapula and clavicle to lift and rotate the shoulder joint. Shenzhen Second People’s Hospital, Department of Sports Medicine, Haifeng Liu When the arm is exercised vigorously or lifted excessively, the rotator cuff surface is brushed or struck by the shoulder crest, causing damage to the shoulder joint and resulting in localized pain and limited movement. The trauma may be acute such as lifting heavy objects, falling, or being pulled by an external force. Those who play tennis, baseball, badminton, swimming and other sports that require the upper extremities to be raised above the head are also more likely to have shoulder injuries. Traumatic lesions may be due to bursa, tendon or partial rotator cuff tears, such as periprosthetic impingement, subacromial bursitis, rotator cuff injury, glenoid labral injury, supraspinatus tendinitis, etc. These disorders vary widely in treatment and prognosis. When dealing with these types of injuries, forcible pulling, pushing, or functional exercises such as “wall climbing” can aggravate the existing rotator cuff condition, and should not be ignored. Adhesive Capsulitis Adhesive Capsulitis is commonly referred to as frozen shoulder or frozen shoulder. The main lesion is congestion, edema, exudation, adhesion and contracture of the muscles, tendons, ligaments and joint capsule around the shoulder joint. Frozen shoulder occurs in middle-aged and elderly people between the ages of 40 and 70, with an incidence of about 2% to 5%, accounting for 10% to 15% of shoulder pain, and is more common in women than in men. Frozen shoulder is recurrent and prolonged. Although there is a possibility of self-healing, most of them will have the sequelae of limited shoulder joint movement. Shoulder arthritis Shoulder arthritis is caused by damage to the cartilage layer of the joint, which causes direct bone-on-bone friction and contributes to the creation of bone spurs. At this point, the shoulder joint is no longer smooth or comfortable to move. As the bone spur increases in size, the shoulder joint gradually loses mobility. The pain of shoulder arthritis appears slowly and is particularly painful whenever the shoulder is moved. Therefore, patients who experience shoulder joint pain need to visit a hospital as soon as possible to clarify the cause and get timely treatment in order to reduce the pain.