The symptoms of pain in the middle of the spine when waking up or sleeping may exist for the following reasons: 1, the most common reason, most of them are because the mattress is too soft, when lying on it, it will put the spine in a state of excessive hunchback or spinal scoliosis, which will make the ligaments between the spine, joints and back muscles are strained, after sleeping because of long periods of inactivity, and lead to ligament, joint or 2. people who work hard during the day, maintain an arching back and bending posture for a long time, or sit and stand for a long time may also experience spinal pain when sleeping or after sleeping. 3. spinal tumors may also have this symptom, but this is relatively rare and requires a spinal x-ray or MRI to further confirm the diagnosis.