Many middle-aged and elderly people have suffered from “frozen shoulder” and shoulder pain, which makes them think that shoulder pain must be frozen shoulder. In fact, shoulder pain can sometimes be a sign of certain diseases. Coronary heart disease is a heart disease caused by narrowing or spasm of the coronary arteries. During an attack of coronary heart disease, angina pectoris occurs due to ischemia and hypoxia of the heart muscle, which is a crushing pain located behind the sternum or in the precordial area. Due to nerve reflexes, coronary heart patients sometimes exhibit shoulder pain symptoms, which may even mask the pain in the precordial region. Therefore, the presence of shoulder pain should sometimes alert to coronary heart disease. However, because the attack of angina pectoris in coronary artery disease usually lasts for a short time, shoulder pain is paroxysmal and short-lasting, and it is mostly left shoulder pain with a feeling of heaviness, and shoulder joint movement is not affected. Gallstones and cholecystitis When gallstones and cholecystitis attack, they can also cause shoulder pain due to nerve reflex. However, patients with gallstones and cholecystitis mainly present with pain in the back of the right shoulder, along with right upper abdominal pain, fever, jaundice, nausea and vomiting, and often have acute onset after eating fatty foods. Cervical spondylosis is caused by degenerative changes in the cervical intervertebral disc, which leads to compression of the intervertebral space, relaxation of the intervertebral ligaments and joint capsule, and instability of the cervical joints, causing a series of pathological changes in the cervical bones and joints and soft tissues of the neck, resulting in various symptoms. Clinically, cervical spondylosis can have a variety of manifestations, one of which is called nerve root type, that is, the nerves governing the upper limbs are stimulated and compressed, at which time shoulder pain, numbness and pain in the upper limbs, finger movement and other manifestations will occur. In this case, cervical spine X-ray or CT examination can be used for diagnosis. Apical lung cancer There are many plexuses in the peripheral area of lung water, including cervical plexus that innervates the skin and muscles of the neck, and wall plexus that innervates the skin and muscles of the back of shoulder and upper limbs. When cancer develops in the lung apical region, the growing cancerous tissue may compress or invade these plexuses, causing pain in the shoulder, especially at night. If the plexus is severely compressed, it can also affect the movement of the shoulder and upper limbs. Therefore, if shoulder pain cannot be relieved or even worsened by the treatment of frozen shoulder, and is accompanied by coughing and hemoptysis and deterioration of general condition, you should go to the hospital to investigate the cause of the disease.