Shoulder pain can be caused by physiological factors such as improper posture at work and study or overwork, as well as diseases such as rotator cuff injury, frozen shoulder, and other diseases such as cervical spondylosis. 1. Physiological factors: Patients may have incorrect postures at work or study, or when sleeping, leading to shoulder compression, or patients may have over-use of the shoulder, which will lead to the phenomenon of soreness in the shoulder crevice. 2. Rotator cuff injury:Rotator cuff injury is caused by indirect violence and other factors, patients will have shoulder pain, localized swelling, limited movement and other symptoms. As a result, patients will have soreness in the shoulder crevice. 3. Frozen shoulder:Frozen shoulder is mainly caused by joint capsule fibrosis and synovitis and other diseases, and the main symptoms of patients are shoulder pain, shoulder stiffness, cold shoulder and so on. As a result, patients will experience soreness in the shoulder crevices. 4.Other:Cervical spondylosis, bone tumor, coronary heart disease and other diseases can also lead to the symptoms of shoulder pain. If the patient has symptoms of shoulder pain, it may be caused by physiological factors and does not require special treatment. If it is a disease that causes shoulder pain, the patient should consult a doctor in time and follow the doctor’s instructions for treatment.