Sleeping up special pain in the back may be due to improper sleeping posture caused by the physiological phenomenon, may also be due to lumbar muscle strain, ankylosing spondylitis and other diseases. 1. Physiological phenomenon: usually the patient sleeps in an improper posture, resulting in local muscle tension, often appear to sleep up special pain in the waist symptoms, is a normal physiological phenomenon. 2. Lumbar muscle strain: usually due to chronic strain of the lumbar muscles, ligaments and other conditions, and also related to obesity, acute injury, smoking, drinking and other factors. Patients often appear recurrent lumbar pain, can also be manifested as lumbosacral pain and discomfort, sacrospinal muscle mild pressure pain. Some patients may also have a special pain in the waist after a sleep. 3. Ankylosing spondylitis: the cause of the disease is still unclear, mostly considered to be related to the environment, immunity, genetics, infection and other factors. The onset of the disease is slow, early patients often appear lumbosacral dull pain, morning stiffness and other symptoms, and will also appear in the middle of the night to turn over the difficult situation, which can also be manifested as a sleep up special pain in the waist. It is recommended that the patient sleeps up a special pain in the waist, timely find out the cause of the disease, if it is caused by the disease, but also need to actively seek medical treatment.