Back pain, but in an irregular location, is most likely due to intercostal nerve irritation. The intercostal nerve is the most extensive lesion in the back that can cause pain. Once the intercostal nerve is compressed or injured, or if the intercostal nerve becomes infected or inflamed, it can cause pain in the back in an irregular location, and there may be symptoms of pain in the back, side chest, or anterior chest. A common cause of intercostal nerve irritation is thoracic spondylolisthesis. Patients with thoracic spondylolisthesis may experience relief after lying down and resting, and the pain may worsen after a long period of fixed posture. Some patients with chronic intercostal neuralgia also have back pain, and the location is not fixed, but generally no other symptoms, the pain is not regular, and there is no direct relationship with the chest activities, the symptoms must be timely examination, and timely treatment after diagnosis.