There are many causes of pain in the middle of the upper back, such as supraspinatus ligamentitis, lumbar muscle strain, acute necrotizing pancreatitis, acute myocardial infarction and so on. 1. Supraspinous ligamentitis: The supraspinous ligament is in the position of the spinous process, and if it is repeatedly subjected to friction, it will cause inflammatory edema, which can cause pain in the middle of the upper back. 2. Lumbar muscle strain: chronic strain on the muscles of the lower back can also cause pain in the middle of the upper back, usually accompanied by lumbar pain, lumbago and other phenomena. 3. Acute necrotizing pancreatitis: the pancreas is located in the upper back of the human body, if the pancreas is infected, oozing, due to the pancreatic enzymes have a corrosive effect on the surrounding tissues, can also lead to pain in the middle of the upper back. 4. Acute myocardial infarction: Acute myocardial infarction can occur due to acute contraction of the heart vessels. There are many reasons for the pain in the middle of the upper back, it is recommended to go to the hospital in time to improve the examination after the symptoms appear, and give standardized treatment after a clear diagnosis.