Lying in bed with back pain up to not hurt may be the lumbar dorsal myofasciitis, ankylosing spondylitis, osteoporosis and other diseases. 1. Lumbar dorsal myofasciitis: studies have shown that the occurrence of this disease and acute lumbar back sprain, lumbar back muscle strain, can be induced by maintaining a long time in a bad posture, moisture, cold and other factors, resulting in patients appearing to lie down on the bed with back pain and no pain. 2. Ankylosing spondylitis: the etiology of this disease is not clear, and currently clinically believed to be related to heredity, infection, immunity, environment, increased pressure on the spinal pressure point and other factors. Typical symptoms include low back pain, stiffness, etc. Pain is mainly characterized by resting pain, which can be manifested as lying in bed with back pain and no pain. 3. Osteoporosis: this disease is mainly due to the reduction of bone formation, but bone resorption caused by an increase in the reduction of estrogen, age, bone metabolism regulation abnormalities and other factors, or secondary to hyperthyroidism, rheumatoid arthritis and other diseases, some of the patients will exist in lying in bed when the back pain is up and no pain performance. It is recommended that patients with back pain in bed go to the hospital to clarify the specific causes.