Lumbar keyboard herniation can be divided into three stages of development: 1, pre-herniation This period of nucleus pulposus can become fragmented due to degeneration and injury, and the annulus fibrosus can become thin, soft or produce fissures. 2, herniation period When the intervertebral disc undergoes increased pressure and imbalance, the degenerated nucleus pulposus can be protruded from the weak place of the annulus fibrosus or rupture, and five situations can occur: (1) annular bulging of the annulus fibrosus: bulging between the posterior margins of the adjacent vertebrae, with intact annulus fibrosus i.e., Bulging. (2) confined bulging of the annulus fibrosus: confined bulging of the annulus fibrosus, but intact annulus fibrosus, which can produce clinical symptoms. (3) Herniated disc: the protruding nucleus pulposus is restrained by the very thin annulus fibrosus, which can produce typical symptoms. (4) Prolapsed disc: the protruding nucleus pulposus passes through the completely ruptured annulus fibrosus and reaches the posterior longitudinal ligament. The nucleus pulposus may be located above or below the nerve root, or in the anterior middle of the spinal canal. (5) Free type herniated disc: the nucleus pulposus passes through the ruptured annulus fibrosus and posterior longitudinal ligament, and is free in the spinal canal or even located in the intradural or subarachnoid space, which oppresses the cauda equina nerve or nerve root. 3.Late stage of herniation Fibrosis or calcification of intervertebral disc herniation. Degeneration of intervertebral disc, crumpling of the annulus fibrosus, narrowing of the intervertebral space, sclerosis of vertebral bone and formation of bone capillaries. Nerve root damage, long-term compression can lead to adhesion, degeneration and atrophy of the nerve root. Hypertrophy of the ligamentum flavum, a secondary lesion, can lead to spinal stenosis. Degeneration and hyperplasia of the intervertebral joints, due to the narrowing of the intervertebral space, the intervertebral joints of the compensatory load increases, and degenerative spinal stenosis occurs.