Once lying in bed, the lumbar region will make a loud noise, and this condition is most likely caused by lumbar disc herniation. Lumbar disc herniation refers to the lumbar intervertebral cartilage protruding outside the entire lumbar spine structure, and may compress the soft tissue around the spine to produce a series of symptoms, especially when standing, sitting or bending, the lumbar spine will be subject to exponential pressure, especially the lumbar intervertebral disc, the entire lumbar spine pressure is mostly shared by the lumbar intervertebral disc. So patients suffering from lumbar disc herniation, during the day or work, the lumbar disc is in a state of protrusion, when a lie down when the pressure on the lumbar spine is instantly reduced, the disc may immediately shrink back to the vertebral body after the pressure is lifted, resulting in the emergence of loud sounds. There are also some previous repeated twisting waist, flashing waist situation occurs, lumbar intervertebral ligaments are repeatedly damaged and lead to calcification, when a lie down when the lumbar intervertebral ligaments stretch deformation, there may also be a loud sound.