Endoscopic techniques currently used for the treatment of lumbar disc herniation include: laparoscopic lumbar disc removal, posterior microendoscopic lumbar discectomy (MED), expandable tube endoscopic lumbar discectomy, and percutaneous endoscopic discectomy (PELD), and the progress of these minimally invasive endoscopic techniques is reviewed below. In 1991, Obenchain first reported laparoscopic anterior lumbar L5/S1 discectomy via the abdominal approach. In 2000, Bezawa et al. suggested that a laparoscopic lateral retroperitoneal approach could be used to manage extreme posterolateral lumbar disc herniation and nerve root canal decompression in the L1-S1 segment, particularly in the L5/S1 segment. Laparoscopic anterior lumbar herniated disc nucleus pulposus removal has the following advantages: less surgical trauma, less bleeding, low chance of accidental injury under laparoscopic surveillance; exact decompression hole of the fibrous ring, complete nucleus pulposus removal; short postoperative bed time (2-3 d), favorable extrusion of residual nucleus pulposus tissue; low impact on spinal stability; no nerve root and dural sac adhesions and compression; good reproducibility of surgery. Laparoscopic lumbar disc removal is indicated for cases with simple lumbar disc herniation, intact fibrous annulus and/or posterior longitudinal ligament, no upward or downward displacement of the herniated disc, and no obvious spinal stenosis, synovial hyperplasia, or hypertrophy of the ligamentum flavum. Possible complications include intra-abdominal organ injury and large vessel injury, arteriovenous thrombosis, ureteral injury, retrograde ejaculation, etc. Patients with a history of severe abdominal trauma and severe cardiopulmonary disease are not suitable for laparoscopic surgery. The posterior microendoscopic lumbar discectomy (MED) was developed and first reported by Foley and Smith in 1997, which perfectly combines the traditional open surgical method with modern minimally invasive endoscopic technology to make open lumbar discectomy minimally invasive and endoscopic. The operation can be completed by biting off only a small portion of the lamina margin, which maximizes the stability of the lumbar spine and reduces postoperative dural sac adhesions. MED technology will make the surgical treatment of lumbar discs more minimally invasive and effective, which is the direction of future development and efforts. The correct selection of surgical indications is the key to the success of MED. Because of the limited space and two-dimensional surgical field of view, MED endoscopic surgery requires not only high requirements for surgical instruments, but also high tactile sensitivity and spatial discrimination, and the ability to operate with “hand-eye separation”. Improper selection of surgical indications is an important reason for the poor outcome of MED surgery. The selection of indications for MED surgery is more cautious and strict than that for traditional open surgery, and the principle of selecting indications for surgery in stages from superficial to deep and from easy to difficult has been proposed; the complication rate of MED surgery is low, and the most common ones in clinical practice are dural tears (2.5%-6.9%), followed by bleeding, intervertebral space infection (0.5%-3.2%), nerve root injury and positioning errors. Most of them are related to improper selection of surgical indications, poor grasp of surgical indications, inappropriate preoperative assessment, and unskilled operation. The METRx is designed to facilitate intervertebral bone graft fusion and fixation after minimally invasive decompression. The METRx endoscopic system is the second generation of METRx endoscopic system introduced by SOFAMOR DANEK, USA, based on the original MED system. Compared with the original MED system, the METRx system has significantly improved the image quality, instrument type, and operating space. The treatment of lumbar degenerative disc disease with METRx is a minimally invasive technique that is performed in a small space by establishing a working channel, using endoscopic observation, and applying special tools. However, the operation is different from traditional open surgery and requires a higher level of operator, with a steeper learning curve and special surgical complications such as positioning errors and deviations in canal placement, dural injury, nerve root and cauda equina injury, and large vessel injury. IV Percutaneous endoscopic discectomy (PELD) Since Valls et al. described percutaneous vertebral biopsy in 1948, percutaneous procedures have been steadily updated in terms of both instrumentation and technique. In 1986, Schreiber et al. introduced arthroscopy into percutaneous myelomeningocelectomy with an excellent rate of 95%. In 1993, Mayer and Brock used a modified percutaneous endoscopic technique with an angular endoscope and flexable instruments to achieve the same results as open surgery. With the improvement of surgical instruments and the accumulation of surgical experience, percutaneous endoscopic discectomy (PELD) has been continuously developed. The implementation of PELD requires a deep understanding of the anatomy around the annulus fibrosus, the safety triangle, the subscopic site of the annulus fibrosus, the nerve root foramen and the subscopic appearance of the nerve root, as well as the need to alternate between the endoscope and the operating instruments during the operation, which cannot be done simultaneously under direct vision. The narrow field of view and intervertebral foramen and the steep learning curve of the operation limit its clinical application. Whether compared with traditional open surgery or microdiscectomy and microendoscopic discectomy, PELD has the advantage of being more minimally invasive in the treatment of extreme posterolateral lumbar disc herniation with minimal bleeding; local anesthesia is safe and reliable, and the herniated disc is fully removed by endoscopy and the nerve root is directly decompressed, and the patient can feel improvement in nerve root symptoms immediately after surgery. The use of PELD tissue damage is light, and patients can leave bed and be discharged the next day after surgery. The indications for PELD depend on the patient’s anatomical limitations of the endoscopic procedure itself, as well as the surgeon’s technical mastery and experience with endoscopic surgery. Contraindications are determined by the surgeon’s surgical experience and skill, but pregnancy, severe spinal degeneration, spinal stenosis, spinal instability, intracanalicular adhesions, and free nucleus pulposus tissue are contraindications. The advantages of FLD include small incision, limited tissue damage, good illumination in the operative field, easy operation, minimal damage to the stable structures of the spine, more complete resolution of nerve root compression, avoidance of injury to the nerve roots and dural sac, and rapid recovery of the patient after surgery. The indications for FLD are that the disc nucleus pulposus has been considered clinically, that there are clear surgical indications for the procedure, and that the patient is generally under 50 years of age. Relative contraindications to surgery include: intermittent claudication, typical lumbar spinal stenosis, symptoms not compatible with physical examination, developmental, degenerative, or hyperplastic spinal stenosis confirmed by CT and MRI, and severe calcification and ossification. The application of the above-mentioned endoscopic techniques in the treatment of lumbar disc herniation all have the advantages of less trauma, less bleeding, faster recovery, fewer complications, and the ability to maintain the stability of the spine without obvious scar or adhesion formation after surgery, and have become a new trend in the treatment of LDH. With the further improvement of operating techniques and surgical instruments and research on factors related to disc recurrence, minimally invasive endoscopic treatment of lumbar disc herniation in the spine has developed rapidly, but we should strictly grasp the principles, indications and contraindications of various therapies when using minimally invasive endoscopic techniques to treat lumbar disc herniation, and adopt individualized treatment plans for patients without blindly expanding the indications for surgery.