Basic etiology: 1, degenerative changes in the lumbar intervertebral disc is the basic factor: degeneration of the nucleus pulposus is mainly manifested as a reduction in water content, and can cause small-scale pathological changes such as vertebral joint instability and loosening due to water loss; degeneration of the fibrous ring is mainly manifested as a reduction in the degree of toughness. 2, injury: long-term repeated external forces cause minor damage, aggravating the degree of degeneration. 3, the weakness of the intervertebral disc’s own anatomical factors: the disc gradually lacks blood circulation in adulthood and has poor repair ability. On the basis of the above factors, some kind of triggering factor that can lead to a sudden increase in the pressure on the intervertebral disc may cause the less elastic nucleus pulposus to pass through the fibrous ring that has become less tough, causing the nucleus pulposus to protrude. 4, genetic factors: lumbar disc herniation has been reported to have familial onset, the incidence of this disease in people of color is low. 5, lumbosacral congenital anomalies: including lumbar sacralization, sacral lumbarization, hemivertebral deformity, small joint deformity and joint protrusion asymmetry, etc.. The above factors can cause changes in the stress on the lower lumbar spine, which constitutes an increase in the internal pressure of the intervertebral disc and predisposes to degeneration and injury. Triggering factors: On the basis of degenerative disc degeneration, a certain factor that can induce a sudden increase in intervertebral disc pressure can lead to nucleus pulposus herniation. Common predisposing factors include increased abdominal pressure, lumbar malposition, sudden weight bearing, pregnancy, exposure to cold and moisture, etc. Clinical typing and pathology: The following typing can be made from the pathological changes and CT and MRI performance, combined with treatment methods. 1, bulging type: partial rupture of the fibrous ring, while the surface layer is still intact, the nucleus pulposus is limited to bulge into the spinal canal due to pressure, but the surface is smooth. Most of this type can be relieved or cured by conservative treatment. 2, protruding type: complete rupture of the fibrous ring, the nucleus pulposus protrudes into the spinal canal, covered only by the posterior longitudinal ligament or a layer of fibrous membrane, the surface is uneven or cauliflower-shaped, often requiring surgical treatment. 3, prolapse free type: rupture of the protruding disc tissue or fragments into the spinal canal or completely free. This type can not only cause nerve root symptoms, but also easily lead to cauda equina symptoms, non-surgical treatment is often ineffective. 4, Schmorl node: the nucleus pulposus enters the cancellous bone of the vertebral body through the fissure of the upper and lower endplate cartilage, generally only have back pain, no nerve root symptoms, most do not need surgery.