Lumbar intervertebral discs are not only the main solid connection between the vertebrae to support the structure, but also the main structure of the spinal column movement and elimination of shock, to maintain the normal physiological posture of the entire body and to ensure that the torso for a variety of sports, plays a special role, its specific functions are as follows: 1, to maintain the height of the spinal column, to maintain the height, along with the development of vertebrae, intervertebral discs are also heightened, which increased the height of the spine and the mobility. The intervertebral discs also increase in height and mobility of the spine. 2.Connect the upper and lower vertebrae, and make the vertebrae have a certain degree of mobility. 3.To equalize the pressure on the surface of the vertebrae. When there is a certain inclination between the vertebrae, the pressure is broken down by the semi-liquid component of the nucleus pulposus, so that the whole intervertebral disc is subjected to the same pressure. 4.Because of the elastic structure, especially the nucleus pulposus has a certain degree of plasticity, it can be deformed under pressure, so that the force applied to it can be transmitted to the annulus fibrosus and cartilage plate in all directions on an even basis. 5.It is the main structure of spinal column to absorb shock, and plays the role of elastic cushion, so that when falling from a high place or when the shoulder, back and waist are suddenly subjected to force, it can cushion the pressure through the conduction of force and its own deformation to protect the spinal cord and the important organs of the organism. 6.Assisting in maintaining a certain distance and height between the lateral articular processes. Maintain the size of intervertebral foramina so that the nerve roots have enough space to pass through the intervertebral foramina. 7, to maintain the physiological curvature of the spine, different parts of the intervertebral disc thickness varies, in the same lumbar intervertebral disc in the anterior thick, the posterior thin, in the thoracic spine is thin in the anterior, the posterior thick, so that the spinal column appears lumbar forward convex, thoracic vertebrae backward convex physiological curve.