In the early days of MED, the technique was considered to be difficult and demanding, with more complications than conventional surgery. Therefore, the selection of indications was very strict, including persistent radiating pain, numbness or weakness in the unilateral lower extremity; clear localization of nerve root compression; and objective imaging data (CT, MR I) confirming a unilateral disc herniation with a single gap that has failed to respond to 6 weeks of conventional conservative treatment. Nowadays, with the increase of surgical proficiency and the improvement of surgical instruments, the indications and indications for surgery have become wider and wider. Zhou Yu et al. used MED technique to perform nucleus pulposus resection and nerve root decompression release in 9 patients with extreme posterolateral lumbar disc herniation by transverse intertransverse approach, and the postoperative excellent rate was 89% using Nakai classification. For a long time, postoperative recurrence of lumbar disc herniation was considered a contraindication to MED surgery because of the destruction of normal tissue structure and epidural scar growth and adhesions, which made reoperation very difficult. However, with the development of minimally invasive techniques and increased operator proficiency, it is now possible to perform good secondary surgery under MED. Ahn et al. applied the MED technique to remove the disc and release the nerve roots in 43 patients with recurrent disc herniation after open surgery, and the postoperative symptom relief rate was 95.3%, and he also pointed out that the minimally invasive approach provides a clearer local field of vision and a more delicate operation, and has better results in dealing with adherent tissue than open surgery. With the development of MED technology and the widespread acceptance of minimally invasive concepts, techniques such as X-TUBE, SEXTANT, and B-TWIN, which are based on MED, have made it possible to perform some of the things that were previously only possible with open surgery, such as slipped vertebral body repositioning, internal fixation with pedicle screws, and interbody fusion, with minimal trauma. The METRX system is based on this technology, which provides a wide range of access to the surgical area. The METRX X-Tube access tube is inserted outside of the dilated tube in the same manner as the access tube of the METRX system, and the opening tool of the METRX X-Tube dilated access tube system is inserted into the dilated access tube and expands the bottom of the access tube, thus expanding the diameter of the access tube to 4.0 cm. Tae et al. compared the X-TUBE technique for pedicle screw fixation and intervertebral fusion in sheep with open surgery and concluded that the results were comparable to those of open surgery, but with much less tissue damage than open surgery. Foley et al. used the SEXTANT system to perform posterior lumbar interbody fusion with internal fixation in 15 patients with disc degeneration and achieved good results. The average hospital stay was only 2.4 d, and all patients were relieved after surgery, and there was no significant difference between the fusion results on radiological examination and open surgery. In contrast, the B-TWIN technique, in which the interbody fusion is inserted into the intervertebral space through a unique placement device under the MED, is safer and more stable than conventional interbody implants, and Folman et al. used the B-TWIN technique for interbody fusion, which resulted in significant postoperative restoration of interbody height and a significant reduction in complications compared with conventional interbody implants.