Lumbar spinal stenosis is a group of syndromes in which abnormal narrowing of the lumbar spinal canal leads to compression of the cauda equina and/or nerve roots and causes the corresponding clinical symptoms, and its “syndrome” refers to intermittent claudication. According to the anatomical classification, lumbar spinal stenosis can be divided into central canal stenosis and nerve root stenosis, and the stenosis usually occurs at the level of the intervertebral disc, and the common causes of stenosis are disc herniation or bulge, bone formation, synovial hyperplasia and ligamentum flavum hypertrophy. The causes of lumbar spinal stenosis leading to clinical symptoms are controversial and the following theories exist: mechanical compression, venous stasis, inflammation and lumbar instability. Clinical manifestations are the basis for the diagnosis of lumbar spinal stenosis, and imaging spinal stenosis is not the same as clinical spinal stenosis. However, imaging is an important adjunct to determine the site, extent, and segment of spinal stenosis, whether it is central canal stenosis or neurogenic stenosis, bony stenosis or soft tissue stenosis, or both. For patients with intractable pain, progressive neurological impairment, and ineffective conservative treatment, surgical treatment may be indicated. Isolated low back pain is not an important indication for surgery because it is difficult to obtain effective relief with surgical treatment. The goal of surgery is to relieve pain and improve quality of life. The key to successful surgery is complete decompression of all involved nerve tissue, the extent of which depends on an accurate analysis of the pathological anatomy. The key to ensuring the long-term outcome of the surgery is to maintain the stability of the spine. The choice of surgical approach depends on the following factors: the level of lumbar spinal stenosis, the number of segments involved, the site of stenosis, the presence of associated deformities, and the presence of signs of lumbar instability. In general, a stable spine requires only decompression surgery and should be treated according to the segment that produces the clinical signs and symptoms, i.e., the “responsible segment”. Nerve root canal stenosis should be decompressed by opening a window, and bilateral root symptoms should be decompressed by opening a window bilaterally; central canal stenosis should be decompressed by total laminectomy; extensive decompression is required for both central and nerve root canal stenosis. Long-segment spinal stenosis without clinical signs and symptoms on imaging does not require prophylactic decompression. Indications for fusion include: preoperative segmental instability, degenerative slippage, degenerative scoliosis, recurrent decompression of the same segment, and excessive decompression resulting in a large structural defect with medical instability (bilateral synovectomy >50%, unilateral total joint resection). The fusion modalities are posterior-lateral intertransverse fusion and interbody fusion. Interbody fusion is the most reliable fusion method because it can effectively restore the height of the intervertebral space and the anterior lumbar convexity and can effectively transmit the load with a high fusion rate. However, posterior lateral intertransverse fusion is still an effective bone grafting fusion method. The key is to deal with the bone grafting bed, and it is recommended to use autologous iliac bone as much as possible and ensure abundant bone grafting. The choice of fusion method needs to follow the principle of individualization, and it should be selected appropriately according to the patient’s general condition, the cause of nerve compression, the degree of slippage, the height of the vertebral space, and the expected decompression scheme. Whether internal fixation should be performed at the same time as implant fusion is still controversial. The use of internal fixation can help to re-establish spinal stability and improve the rate of spinal fusion, but it does not improve outcomes per se and may increase operative time, bleeding, and the incidence of nerve injury. The use of internal fixation should be based on fusion; without good fusion, internal fixation will eventually fail. In principle, the scope of internal fixation should be taken as short as possible for segmental fixation. In recent years, some scholars have applied the dynamic stabilization system in the treatment of lumbar spinal stenosis. The dynamic stabilization system, also known as soft fixation or flexible fixation, only fixes the lumbar spine without fusion. The system is placed in the posterior aspect of the spine in a guarded tension state, which can increase the local anterior convexity of the spine and limit the range of motion of the unstable segment, thus restoring the stress transmission pattern of the moving segment to normal or near normal and thus relieving pain. By allowing some movement of the fixed segment, it does not have a significant effect on the motion of adjacent segments and may reduce or avoid the occurrence of degeneration of adjacent segments. However, its long-term efficacy remains to be observed with further follow-up.