For a long time, due to the misunderstanding of shoulder joint injury, people used to categorize many shoulder-related diseases as “frozen shoulder”, not knowing that in many cases, “rotator cuff tear” is the real “culprit! “The problem is that the rotator cuff tear is the real culprit in many cases. Due to the lack of knowledge and incorrect diagnosis, many patients go farther and farther down the road of treatment. What are the early symptoms of rotator cuff injury? 1.History of trauma: the history of acute injury, as well as the history of repetitive or cumulative injury, has reference significance to the diagnosis of this disease. 2.Pain and pressure pain: the common site is anterior shoulder pain, located in the anterior and lateral deltoid muscle. Acute pain is severe and persistent; chronic pain is spontaneous and dull. Symptoms are aggravated after shoulder activity or increased load. The pain is also aggravated by passive external rotation of the shoulder. Nighttime exacerbation of symptoms is one of the common clinical manifestations. Pressure pain is mostly seen in the proximal part of the greater tuberosity of the humerus, or in the area of the subacromial space. Functional disorders: In large rupture of rotator cuff, active shoulder elevation and abduction are limited. The range of abduction and forward elevation is less than 45°. However, the passive range of motion is not significantly limited. Muscle atrophy: if the history of the disease is more than 3 weeks, the muscles around the shoulder have different degrees of atrophy, with the deltoid, supraspinatus and infraspinatus muscles being more common. 5, secondary contracture of joints: if the history of the disease is more than 3 months, the range of motion of the shoulder joint is limited to different degrees, and the limitations of abduction, external rotation and supination are more obvious. It is not easy to make a correct diagnosis of rotator cuff rupture. The possibility of rotator cuff tear should be considered in patients with a history of shoulder trauma and anterior shoulder pain with tenderness in the proximal aspect of the greater tuberosity or subacromial region. If accompanied by muscle atrophy or joint contracture, the lesion is in an advanced stage. In suspected cases of rotator cuff rupture, radiographs of the affected shoulder, arthrography, CT examination, magnetic resonance imaging, ultrasonography and arthroscopy should be performed, which will help to establish the diagnosis.