The pain next to the chest may be related to muscle strain, intercostal neuritis, breast disease, cardiovascular disease, respiratory disease and so on. 1. Muscle strain: such as prolonged incorrect posture, cold, overwork and other causes of muscle and fascia localized congestion and adhesion, resulting in aseptic inflammation, can cause pain symptoms. 2. Intercostal neuritis: generally caused by nerve compression, infection, trauma, etc., which can cause stimulation to the intercostal nerve, causing inflammatory reaction of the intercostal nerve and pain symptoms. 3. Breast diseases: such as breast hyperplasia, mastitis, breast tumor, etc., due to hormone level changes, inflammation stimulation, tumor invasion and compression, etc., pain next to the chest, bacterial infections, mammary ducts, etc., may also cause local redness, swelling, fever and other symptoms. 4. Cardiovascular diseases: such as angina attack in patients with coronary heart disease, pain in the anterior region of the heart, chest tightness, shortness of breath and other symptoms, manifested as pain next to the chest. 5. Respiratory diseases: such as pneumonia, pulmonary embolism, pleurisy and other diseases, can also cause chest pain. It is recommended that patients with pain next to the chest go to the hospital in time, complete the relevant examinations, find out the cause and then treated under the guidance of the doctor.