Lumbar disc herniation is a common and frequent disease in spine surgery, and is one of the most common causes of lower back pain and leg pain. Its pathogenesis is a syndrome manifested by degeneration of the lumbar disc, rupture of the annulus fibrosus, and protrusion of the nucleus pulposus, which stimulates and compresses the nerve roots and cauda equina. Most patients with lumbar disc herniation can have their symptoms relieved with conservative treatments such as acupuncture, tui-na, traction and strengthening of the lumbar muscles, but about 15% of patients with lumbar disc herniation eventually require surgery. Mixter and Barr at Harvard Medical School in the United States first used surgery to cure lumbar disc herniation in 1934, and to date, the history of surgical treatment of lumbar disc herniation has reached more than 70 years. After a lot of experimental and clinical research, the diagnostic techniques of this disease have been gradually improved and the surgical methods have been greatly developed and innovated. PLIF surgery (posterior lumbar interbody fusion), in which Cloward restored intervertebral height by repairing the posteriorly resected lamina into a wedge-shaped bone block implanted in the lumbar interbody, achieved good results and was rapidly promoted, after which the method became known as PLIF. The original PLIF surgery was performed after After posterior decompression or/and nucleus pulposus removal, bone grafting was performed on the fused intervertebral space for the purpose of interbody fusion. In order to overcome the shortcomings of bone graft absorption, narrowing of the vertebral space and long postoperative bed rest, various types of interbody fusion devices that are more suitable for the anatomical or pathological structure of the vertebral space have been improved. Indications: 1.Severe lower back pain caused by degenerative changes of the lumbar spine that has been ineffective after more than 1 year of conservative treatment; 2.Discogenic back pain with or without neurogenic pain; 3.Spinal slippage within the range of Ⅰ to Ⅱ degrees; 4.The height of the pre-fused intervertebral space must be less than 12 mm; 5.Failed disc removal; no loss of intervertebral space, infection, or degenerative changes of the adjacent intervertebral space.