The dangers of having a closed joint are usually localized infection, subcutaneous tissue atrophy, and osteoporosis. However, it can be avoided by professional doctors. 1. Local infection: most of the closed injections are glucocorticosteroids, if the patient is frequently injected, it may lead to a decline in resistance and easily cause local infection. 2. Subcutaneous tissue atrophy: If the joints are injected with closed injections for a long time, it may lead to dissolution or atrophy of tendons or subcutaneous tissues, which may lead to spontaneous rupture of tendons in severe cases. 3. Osteoporosis: If joints are frequently injected with closed injections, it may lead to cartilage degeneration and premature degeneration, and may also lead to osteoporosis and other symptoms. Patients should take closed injections under the guidance of a professional doctor, and if discomfort occurs, it is recommended to consult a doctor in time to avoid delays.