The supraspinatus muscle is in the rotator cuff and is the intersection where forces are concentrated around the shoulder. As a result, it is highly susceptible to damage. Especially when the shoulder is frequently abducted, the supraspinatus tendon is easily damaged by compression and friction because it passes through the narrow gap between the subacromial and humeral heads, resulting in aseptic inflammation or tendon rupture. The remaining infraspinatus, subscapularis and teres minor can also be injured at the same time, but the symptoms of the supraspinatus tendon are more prominent. Clinical presentation and diagnosis Shoulder abduction pain, subacromial pressure pain. 1. Ask about the history of trauma, injury and treatment; 2. Check the active and passive range of motion of the shoulder joint, and pay attention to the presence of shoulder abduction pain and subacromial pressure pain; 3. Perform shoulder arthrography and MRI examination as appropriate, or shoulder arthroscopy if possible. Treatment 1. For incomplete rupture, the shoulder should be fixed on the abductor frame for 3 weeks; 2. For complete rupture, the shoulder should be surgically sutured and fixed on the abductor frame for about 4 weeks after surgery; 3. For patients over 50 years old with chronic shoulder pain caused by rotator cuff injury, if conservative treatment is not effective, arthroscopic acromioplasty and rotator cuff repair should be performed.