For patients who develop narrowing of the lumbar spinal space, it is mainly due to disc degeneration and disc herniation. Once the narrowing of the vertebral space occurs, it cannot be cured by conservative treatment. Once degeneration of the disc and disc herniation occur, there is an irreversible change that cannot be restored through conservative treatment to restore the normal disc structure or to restore the narrowing of the vertebral space. However, the narrowing of the intervertebral space can be restored through surgical treatment, which is mainly based on disc replacement surgery to restore the normal intervertebral space structure.