If the left side of the rib cage is vaguely painful, it needs to be combined with the patient’s other medical history, physical examination, and ancillary tests to make a further diagnosis, which is commonly seen in the following clinical situations: 1. Diseases of the chest wall, such as various kinds of costochondritis, rib neuralgia, and herpes zoster. If accompanied by localized pain, it often suggests costochondritis. Intercostal neuralgia is often considered if it is painful when extending or spreading the arm. If the skin is sensitive and there is a herpetic rash at a later stage, it is herpes zoster. 2. respiratory diseases, which can be seen in pleurisy, pneumonia, tuberculosis, tumors, etc. 3. digestive diseases, such as esophagitis patients with extra-esophageal symptoms can also result. 4. cardiovascular diseases, common coronary heart disease, angina pectoris, generally angina pectoris is a pressure-like pain in the precordial area, behind the sternum, which is not too consistent with the described symptoms, but needs to be further clarified at the hospital. 5. 5, functional diseases, such as neurosis, patients do not have organic heart disease, but always feel uncomfortable, but also need to go to the hospital to exclude organic heart disease, in order to diagnose.