Pain on one side of the back may be caused by localized fasciitis, or it may be caused by internal diseases. 1. Localized fasciitis: the back is covered with rich connective tissue, long-term fixed posture or long-term bilateral shoulder joint force imbalance and other reasons may lead to the imbalance of bilateral back muscle strength, causing unilateral back area localized myofascial aseptic inflammation, resulting in metabolite accumulation and back side pain. 2. Visceral diseases: right-sided back pain caused by cholecystitis, gallbladder stones and other diseases; it may also be due to angina pectoris, cardiac infarction caused by the left side of the limbs and the left side of the back pain. The main reason is that the conduction bundles of visceral sensory nerves share a spinal cord segment with the sensory nerves that innervate the surface area of the back, and in visceral diseases they are transmitted to back pain. The pain on one side of the back may also be related to cold, trauma and other factors, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, and then under the guidance of the doctor to give targeted treatment or therapy.