The pain in the middle of the back may have the following causes: first, supraspinous ligamentitis, supraspinous ligament is traveled on the surface of the spinal process, when it has chronic aseptic inflammation, it can appear pain in the middle of the back, at this time we have to carry out relevant investigations, X-ray examination of the thoracic spine, to exclude other diseases for diagnosis. Second, interspinous ligamentitis, interspinous ligamentitis and supraspinous ligamentitis are basically similar in etiology, and can also occur in the middle of the back pain. Third, osteoporotic back pain, when the thoracic spine has osteoporosis, it can appear pain in the middle of the back, which is often accompanied by compression fractures of the thoracic spine, and relevant thoracic spine x-ray and nuclear magnetic examination should be performed to make the diagnosis. Fourth, tumors or tuberculosis of the thoracic spine can cause pain in the middle of the back, often for the pain of the thoracic spine, and then the diagnosis should be made by the relevant nuclear magnetic examination of the thoracic spine.