Left back pain may be the precursor of thoracic sprain, fasciitis, myocardial infarction and other diseases, which can be treated according to different symptoms. 1. Thoracic sprain: thoracic sprain caused by lifting heavy objects or sports, thoracic back pain, pressure pain, especially in deep breathing and coughing, pain symptoms will be aggravated, follow the doctor’s instructions can be oral fen-phen, nimesulide and other drugs to relieve pain. 2. Fasciitis: manifested in the neck, shoulder and back extensive pain, swelling and heaviness, numbness, stiffness, restricted movement. You can take oral ibuprofen and diclofenac sodium and other non-steroidal anti-inflammatory drugs as prescribed by the doctor for treatment. 3. Myocardial infarction: mainly manifested as persistent pain in the anterior thoracic region, irritability, sweating, a sense of imminent death, some patients with pain radiating to the jaw, the left side of the back above. The patient’s left back pain is also seen in other diseases, it is recommended to seek timely medical treatment, according to the doctor’s advice, do not blindly use drugs.