Sternum ringing may be caused by sternum fracture, degenerative changes of sternum joint, sternoclavicular arthritis and other factors. 1. Sternum fracture: If you are involved in a car accident, fall from a height, violent blows and other accidents, it may lead to sternum fracture, resulting in displacement of the sternum, which may produce a bone rubbing sensation, resulting in sternum ringing. 2. Degenerative changes of sternoclavicular joints: If long-term weight bearing, or excessive stretching, it may cause degenerative changes of sternoclavicular joints, which may result in joint pain, impaired mobility, bone rubbing sound and other symptoms. 3. Sternoclavicular arthritis: If non-suppurative inflammation occurs in the region of sternoclavicular joint, localized pain and swelling in the sternoclavicular joint may occur, which may also lead to abnormal friction of the sternoclavicular joint during activities, resulting in sternoclavicular ringing. If sternal ringing occurs frequently and is accompanied by other uncomfortable symptoms, you should consult a doctor promptly to avoid delaying your condition.