Minimally invasive spine technology has the advantages of less trauma, simpler operation, shorter operation time, better efficacy, faster recovery, fewer complications, and affordable price. The essence is to achieve the same or more efficacy with less trauma than traditional surgery. Given the above advantages and the viewpoint of China’s national conditions, most patients are more likely to accept and recognize minimally invasive techniques, both in terms of economic benefits and psychologically. Lumbar disc herniation (LDH) is one of the most common spinal disorders, and scholars at home and abroad have conducted a series of researches on its treatment methods over the years, especially in the minimally invasive treatment of LDH. Lumbar disc herniation is one of the most common diseases of the spine. For a long time, surgeons have insisted on the principle of surgical removal and decompression, such as intervertebral openings for decompression, half-plate decompression, full-plate decompression, and other approaches for disc removal to achieve nerve root release and decompression to relieve patients’ symptoms, however, these traditional surgical procedures have the following shortcomings: long recovery time, trauma, spinal instability The complications such as neuropathic pain referred to by adhesions, scarring, etc. With the development of the times, minimally invasive techniques have been improved and perfected in LDH due to the advent and progress of imaging, interventional radiology and endoscopic technical facilities, and the specific techniques are reviewed. I. Enzymatic nucleolysis The basic principle of chemical nucleolysis is to use the hydrolysis effect of protease to partially dissolve the collagen of the nucleus pulposus and release the water, which eventually atrophies and reduces the pressure in the intervertebral disc, thus releasing the nerve root compression. In 1964, Smith [2] reported that papaya rennet was injected into the lumbar intervertebral disc by posterior lateral puncture to dissolve the diseased nucleus pulposus tissue for the treatment of lumbar disc herniation. Kuh S U et al. reported that percutaneous chemical nucleolysis with minimally invasive surgical discectomy followed by disc implant fusion for disc herniation had satisfactory efficacy rates of 91%, 95%, and 89%, respectively, and Tang Huafeng et al. of Ruijin Hospital of Shanghai Second Medical University in China also started the work of chemical lysis therapy for lumbar disc herniation from 1985, The country has now reached a mature stage. At present, a large number of foreign studies have proved that its therapeutic effect is lower than that of standard discectomy, and the technique has been terminated in some countries [5]. Whether chemical nucleolysis can be used clinically requires further validation in clinical practice [6]. In addition to the general contraindications to surgery, displaced free disc herniation, combined spinal stenosis or lateral saphenous fossa stenosis, low back and leg pain caused by degenerative disc disease, previous neural adhesions due to surgical scars, obvious neurological symptoms, necrotic disc herniation or disc calcification are contraindications to surgery. Professor Bocci of Siena University, Italy, has done a lot of in-depth basic research on the mechanism of action of ozone since the 1980’s. DErne et al. reported that the total efficiency of medical ozone treatment for lumbar disc herniation was 68%, while Muto et al. reported a higher total efficiency of 78%. In terms of the efficacy of lumbar disc herniation. The excellent rate of traditional discectomy is 78.4%-90.6%, and the satisfaction rate of microscopic lumbar disc removal surgery is 92%, while ozone treatment for lumbar disc herniation is reported in foreign literature to have an effective rate between 68% and 80%, which is significantly lower than that of traditional surgery and microscopic lumbar disc removal treatment. In 2004, the Southern Hospital in China reported that 450 cases were treated with this technique, with an efficiency of 75.9%, and the technology of ozone treatment of intervertebral discs in China has been rapidly developed. At present, domestic and foreign research shows that this technique has not been found to have obvious discomfort symptoms, especially in China, this technique is still commonly used. The indications and contraindications for percutaneous percutaneous ozone injection for the treatment of disc herniation have not yet reached a consensus at home and abroad. The indications are: (1) those with obvious clinical symptoms, such as persistent low back and leg pain; (2) those with positive signs of spinal nerve compression or abnormal skin sensation, such as positive straight leg raise test; (3) those diagnosed by CT or magnetic resonance imaging as inclusive and mild to moderate non-inclusive (herniation less than 30% of the spinal canal volume and disc height greater than 50% of the original) combined with radicular compression and the imaging manifestations and clinical signs are consistent; and (4) those who have a herniated disc with a herniated disc. (6) If the conservative treatment is ineffective for 3 months, it is confirmed by imaging that there is a disc lesion in the corresponding plane without nerve heel compression, and other causes of low back pain are excluded. Contraindications are: severe motor nerve impairment on clinical examination; sciatica of non-disc origin or severe degenerative disc disease; severe combined organ disorders that make surgery risky; combined spinal stenosis or lateral saphenous fossa stenosis; disc herniation with calcification, large protrusions that compress the dural sac by more than 50%; nucleus pulposus tissue prolapse into or The nucleus pulposus is prolapsed into or free in the spinal canal or dural sac; combined with vertebral body slippage; those who have undergone surgery or chemical nucleolysis; hyperthyroidism; G6PD deficiency; bleeding tendency and serious psychological disorders. Third, percutaneous laser disc decompression PLDD PLDD was developed on the basis of percutaneous disc removal. In 1987, Choy et al. were the first to report that the treatment of lumbar disc herniation with laser had a satisfactory effect. This procedure has the advantages of less trauma, less bleeding, faster recovery, and no damage to the stability of the spine, with an excellent surgical rate of 70% to 87%. Tassi reported that 92 patients with herniated discs underwent this procedure, with an excellent rate of 89 . 3 %. The complication that often occurs after PLDD treatment is low back pain, with an incidence of 56.9%, which can be relieved by aspiration and decompression, and obvious low back pain, which can be treated by low frequency physiotherapy. The principle of this technology is to replace the above PLD with laser and introduce the laser optical fiber by inserting the working cannula of the intervertebral disc, using the laser energy to vaporize the nucleus pulposus tissue, so as to effectively reduce the pressure inside the disc, and at the same time the herniated nucleus pulposus tissue becomes solidified, which relieves the compression and stimulation of the nerve root and the nerve symptoms. Because of the small trauma, fast recovery, high safety, no postoperative adhesions, scars and other complications, this technique has reached a high level in recent years at home and abroad. The scope of treatment has been expanded. Percutaneous percutaneous lumbar disc removal includes percutaneous manual lumbar disc removal (PLD) and automated percutaneous lumbar discectomy and aspiration (APLD) [11].Hajikata first reported percutaneous lumbar disc removal (PLD) in 1975. The mechanism of treatment is to remove and aspirate a portion of the nucleus pulposus to reduce the pressure within the disc. However, the indications for PLD are limited to patients with simple and acute lumbar disc herniation with leg pain as the main symptom and a few patients with prolapsed or herniated nucleus pulposus in L4-5 and L5-S1 discs. Open discectomy was once considered the gold standard for nerve root pressure relief, and PLD has been shown to be an alternative to open discectomy [12]. There is no academic consensus on how much volume of disc should be removed by PLD. Clinical studies have shown that this technique alone is ineffective, with some clinical symptoms not improving significantly. The emergence of this technique has two important contributions: first, the development of special small instruments, which laid the foundation for a generation of minimally invasive spinal instruments; second, the description of the concept of “safe triangle working area”, that is, the area between the supra-articular process of the nerve root and the upper edge of the vertebral body, in which the posterior-lateral discoscopy is currently performed. Now after domestic and foreign scholars research, in the endoscopic, laser and other techniques, can significantly improve the treatment effect. V. Microscopic and endoscopic-assisted techniques 5. 1 Microscopic lumbar discectomy (M SLD) MSLD is a combination of traditional posterior laminar opening technique and microsurgical technique, which has the advantages of small incision, less trauma, less bleeding and faster postoperative recovery. In 1997, Sm it h and Foly pioneered the use of microendoscopic techniques for LDH surgery, which is indicated for single-stage lumbar disc herniation where conservative treatment has failed. Bing Guo [14] et al. found that MSLD is a more desirable minimally invasive surgical method because of its ease of operation and few complications. MSLD inherits the advantages of traditional microscopic surgery, such as fine operation and adequate hemostasis, and has the minimally invasive features of posterior microendoscopic discectomy (M ED), and relaxes the limitations of MED to a certain extent. 5.2 Posterior endoscopic discectomy MED was first reported by Smith et al. in 1997, and M ED for LDH is a minimally invasive version of conventional surgery and can be the procedure of choice for the surgical treatment of single gap paramedian LDH. Robin et al. reported 150 cases with an excellent rate of 94% and a mean hospital stay of 717 h and return to work of 17 d. Muramatsu et al. Muramatsu et al. reported a comparative study of 70 cases of lumbar disc herniation treated with MED versus 15 cases treated with Love method (posterior approach), in which the average blood loss, recovery time from walking, and postoperative pain medication use of MED were superior to Love method. Shen Weizhong retrospectively analyzed the clinical data of 306 cases of LDH treated with posterior lumbar discoscopy. MED is comparable to the traditional open microdiscectomy technique in terms of improvement of patients’ pain, labor loss, and health function, and the MED technique makes the surgical treatment of lumbar discs more minimally invasive and effective, which is the direction of future development and efforts. 5.3 Completely endoscopic (FE) interlaminar approach for nucleus pulposus removal FE interlaminar approach for LDH is a minimally invasive endoscopic spinal surgery technique developed in recent years. The advantages of this technique are: it is performed entirely endoscopically through a small channel with minimal trauma; it can be performed under direct vision to avoid accidental injury; and it is effective in removing the nucleus pulposus by pushing the nerve root and changing the endoscopic view [15], but it requires some surgical training and experience. 5.4 Trans-anterior laparoscopic disc removal (TPLD) is performed under laparoscopic surveillance through a triangle of no significant structures on the anterior side of L5-S1, and the retroperitoneum is incised on the anterior side of the intervertebral space and the possible median sacral artery is pushed out and positioned correctly. This technique is limited in its widespread use due to fewer orthopaedic matching instruments and a higher rate of intraoperative conversion to open surgery [16]. 5,5 Percutaneous translaminar discectomy (PTED) PTED, radiofrequency thermocoagulation fibrous annuloplasty was applied by Yeung in 1997. The PTED procedure is characterized by direct disc removal through the foramen, foraminal enlargement through a drill and grinder, and fibrous annuloplasty with radiofrequency ablation. It is believed that a transforaminal approach to discectomy can be used for all types of LDH, some cases of foraminal stenosis, recurrent disc herniation, and discogenic low back pain, especially in patients with extreme posterolateral disc herniation. The YESS technique is a single- or dual-channel technique that gradually removes disc tissue from within the disc to the outside, and the TESSYS technique is an extension and expansion of the YESS technique. PTED can be an alternative to conventional microdiscectomy for LDH, except in cases where the disc is free below the inferior pedicle or where the L5-S1 disc protrudes high into the pelvis. Common complications of PTED are intervertebral infection, dural tears, hemorrhage, and nerve root injury. This technique tends to be more minimally invasive and effective, which is the direction of future development and efforts. VI. Intradiscal electrothermal therapy (IDET), also known as intradiscal electrothermal fibrous annuloplasty, involves the insertion of an adiabatic catheter into the intervertebral disc to induce a flexible thermal resistance wire to the posterior and lateral parts of the inner layer of the fibrous annulus, which heats and contracts the collagen fibers on the inner surface of the fibrous annulus, cauterizes granulation tissue, and coagulates nerve fibers [18]. The indications for this procedure are intradiscal rupture type of discogenic low back pain that has persisted for more than a month, failed conservative treatment, negative straight leg raise test, aspiration does not show nerve root compression, and increased pain induced by discography. Saal et al. first reported I DET for discogenic lower back pain in 2000, noting that in single-space I DET, reduction in disc height usually does not affect the outcome, whereas in multi-segment treatment, a 30% or greater reduction in disc height may reduce the outcome of the procedure. Kapural et al. compared the results of I-DET treatment for 1- to 2-segment and multi-segment ruptures and found significant improvements in pain scores and activities of daily living in both groups. The principle of I DET is that heat causes the collagen tissue to solidify and coagulate the lesion and granulation tissue on the annulus fibrosus, which inactivates the nociceptive receptors at the lesion to prevent nociceptive transmission. In addition, the intervertebral disc is a relatively non-vascular distribution of tissue, during the treatment process can be uninterrupted application of heat to it, and through the cerebrospinal fluid circulation outside the disc and the vertebral body blood circulation to take away excess heat, in order to avoid damage to the nerve roots and ligaments and other normal tissue, so that the treatment is more selective and reduce complications. At the same time, the consolidation of collagen tissue and the closure of the fibrous ring enhance the solidity of the intervertebral disc and the stability of the lumbar spine, relieving the pressure on the diseased disc and helping to eliminate the pain symptoms.I DET treatment is still in its initial stage, with few studies reported, and its application value needs further verification. Radiofrequency ablation myeloplasty Radiofrequency ablation myeloplasty was first used for clinical treatment of lumbar disc herniation in the United States in July 2000, and is an advanced minimally invasive technique for the treatment of disc herniation. In 1996, Yeung et al. first reported that 40 patients with lumbar disc herniation were treated with bipolar electrode radiofrequency ablation technique under percutaneous endoscopic guidance, and the total effective rate was 86.4%. The total effective rate was 86.4%. Yao Xiugao, a domestic scholar, showed that radiofrequency current acts directly on the herniated area, ablating part of the nucleus pulposus tissue and achieving decompression of the nerve roots, dural sac, spinal cord and other tissues around the disc to eliminate and relieve symptoms, and can improve local blood circulation and reduce local inflammatory reactions, with an efficiency of 90%. Because the treatment does not require the use of anesthesia, the operation is safe, the radiofrequency needle is small, the patient is less painful, less traumatic, less complications and other advantages, it is believed that the clinical use can be promoted. Summary Scholars at home and abroad agree on the research of minimally invasive treatment of LDH that it is a new trend in the development of spinal surgery. It is favored by doctors and patients because of its small trauma, obvious effect, quick recovery, short hospital stay, relatively low cost, relatively safe operation, and no effect on spinal stability. However, the indications and contraindications for surgery need to be strictly controlled. With the continuous improvement of new technologies such as imaging and robotics, and the continuous standardization of operating techniques, it is believed that LDH minimally invasive treatment technology will reach a newer and higher level.