There are many reasons for shoulder pain, commonly caused by frozen shoulder, cervical spondylosis, myofasciitis of neck and shoulder. 1. Frozen shoulder: long-term bad posture and excessive activities cause chronic injury to the tissues around the shoulder and the shoulder joint, resulting in aseptic inflammation, causing shoulder pain, which may radiate to the distal part of the upper arm on the same side. 2. Cervical spondylosis: For example, nerve root cervical spondylosis can compress the nerve root, and when the nerve is obstructed, it will cause edema, nutrient disorder, and shoulder and arm pain. 3. Cervical and shoulder myofasciitis: after weather changes and cold or chronic muscle strain, causing aseptic inflammation of muscles and fascia. Mainly manifested as neck and shoulder pain, and muscle stiffness and other symptoms, can be radiated to the upper limbs and back. If you have shoulder pain that pulls on your upper arm, it is recommended that you seek medical attention in a timely manner, follow the doctor’s instructions for further examination, clarify the cause with the doctor’s help, and carry out targeted treatment or therapy.