It is common to see patients with sudden onset of severe pain in the shoulder joint who are afraid to move the shoulder joint. These are the typical clinical manifestations of supraspinatus calcific tendonitis. The pathological manifestation of this disease is a lime or toothpaste-like deposit of calcium salts inside the tendon. The exact cause is unknown. When the calcium deposits are confined to the tendon, there are no nerve endings in the tendon, so the patient is usually painless. When the calcium salts start to absorb, thin out and break through the tendon tissue into the subacromial bursa (which has a large number of nerve endings), the patient will experience very severe pain. In other words, the pain is one of the signs that the calcification has started to absorb. However, it is difficult to say exactly how long the absorption period lasts. Treatment: 1. Take oral medication such as Fenbid to relieve the pain, and do local physical therapy to promote the absorption of the lesion. 2. Consider closure of the subacromial bursa (usually with compound betamethasone + lidocaine) to relieve symptoms. 3.If oral medication or closure cannot improve the condition, consider arthroscopy, which is minimally invasive surgery to remove calcification. 4.On the basis of pain control, active functional exercises should be performed, mainly shoulder supination and posterior extension exercises, to avoid adhesions of the tissues around the joint and to prevent secondary frozen shoulder (frozen shoulder) from occurring. To summarize, the core concept of treatment is to reduce the pain symptoms of patients in the resorption phase. The means of pain control is in the following order: oral pain medication -> subacromial bursa closure -> minimally invasive surgery. Active functional exercises are performed on the basis of pain control to avoid the occurrence of adhesions.