Traction with the help of traction devices or the use of medical practitioners against the force, according to the principle of biomechanics, so that the lumbar spine in the opposite direction to get the extraction and stretching and get a method of treatment. Comprehensive traction has the following effects: 1, increase the intervertebral space. Traction pulls open the articular synovial joint, widens the intervertebral space, increases the negative pressure in the intervertebral disc, and reduces the pressure of the intervertebral disc. 2.Loosen the nerve root. For milder or long duration of the disease, traction can relieve the nerve root pressure and release the contracture of ligaments, joint capsules and other tissues. 3.Correct the curvature of lumbar vertebrae. Through the action of traction, the lumbar spine can be gradually corrected and the small joint disorder can be corrected and restored. 4.Relieve lumbar muscle spasm, so that the soft tissues of the lumbar back get sufficient rest, which is conducive to relieving the symptoms of lumbar and leg pain and promoting the absorption of nerve root inflammation.