Frozen shoulder is the name of the condition. It refers to a degenerative, inflammatory disease of the shoulder capsule and the soft tissues surrounding the joint. It belongs to the category of “paralysis” in Chinese medicine. It is more common in people around 50 years of age, so it is called “fifty shoulder”. It is more common in women than in men. The cause of this disease is not yet completely clear, but its onset is related to chronic strain, and patients mostly have a history of trauma. Frozen shoulder is also known as periarthritis of the shoulder joint. It is caused by chronic aseptic inflammation of the muscles, tendons, ligaments, bursa, joint capsule and other soft tissues around the shoulder, which leads to adhesions inside and outside the joint and impedes the movement of the shoulder joint, also known as adhesive shoulder arthritis, fifty shoulder, frozen shoulder, and leaky shoulder. The disease can be triggered by trauma, chronic strain, prolonged inactivity or immobilization, or localized attack by wind and cold. The lesions are widespread, i.e., widespread pain, functional limitation, and pressure pain. Shoulder periarthritis belongs to the category of shoulder paralysis. It is a condition that occurs in middle-aged and elderly people and is characterized by soreness, pain and limited movement of the shoulder joint. It is mostly caused by the decay of the tendons and bones in old age, localized wind and cold, strain and flash, etc., resulting in localized qi and blood blockage. In modern medicine, frozen shoulder is similar to this disease. At the beginning of the disease, shoulder pain is the main cause, with lighter days and heavier nights, and slightly slower after activity, with varying degrees of functional limitation; at a later stage, functional impairment is the main cause, with reduced pain but stiff joints and no lifting of the arms, so the disease is also known as “shoulder condensation”. The clinical manifestations of frozen shoulder (periarthritis of the shoulder) are mainly shoulder pain, impaired movement or stiffness of the shoulder joint, and atrophy of the muscles around the shoulder. Some patients develop from biceps tenosynovitis, supraspinatus, and subacromial bursitis. The disease is more common in middle-aged and elderly people over 40 years old, more women than men, and more left shoulders than right shoulders, with a slow onset and long course. It starts slowly and has a long course. It starts with mild shoulder pain and shoulder joint movement disorder, and then gradually worsens and can radiate to the neck, ear and forearm. The affected hand cannot touch the trouser pocket, tie the trouser belt, touch the back, comb the hair, or even wash the face or rinse the mouth. After a few months or even longer, the pain gradually subsides and the function slowly recovers, and finally heals itself. Frozen shoulder (periarthritis of the shoulder) can be complicated by joint contracture dysfunction.