According to the different anatomical structures and etiologies of the lumbar spine, lumbar spondylolisthesis can be categorized into six major categories: dysplasia of the vertebral arch, cleft isthmus of the vertebral arch, degenerative, traumatic, pathologic, and medically induced [7–8], and surgical treatment is the first choice to resolve lumbar spondylolisthesis in patients with II lumbar spondylolisthesis accompanied by intractable pain or neurological deficits and ineffective conservative treatment 9[9]. Open lumbar fusion is the traditional procedure for the treatment of lumbar spondylolisthesis, but this procedure requires extensive stripping of soft tissues such as the lumbar muscles and prolonged distraction, which leads to nerve damage and insufficient blood supply to the paravertebral muscles, thus increasing the incidence of chronic pain [10–11]. The paravertebral muscles are critical for supporting spinal extension, maintaining lumbar lordosis and achieving dynamic spinal stability, so the risk of medically induced injury to the paravertebral muscles should be minimized during surgery [12–13]. The development of spinal endoscopic techniques has brought new opportunities for the treatment of lumbar spondylolisthesis, offering new possibilities for patients to achieve faster and more effective rehabilitation by providing more precise observation and manipulation in a minimally invasive manner [14]. Currently, spinal endoscopic techniques can be categorized into single-channel spinal endoscopic lumbar interbody fusion (PELIF) [15] and unilateral biportal endoscopy (UBE) [16], depending on the number of channels. UBE) [16], which can be broadly categorized into transforaminal lumbar interbody fusion (Endo-PLIF) [17], transforaminal lumbar interbody fusion (Endo-TLIF) [18], and oblique lateral approach lumbar interbody fusion (Endo-OLIF) [19] according to the approach, and the selection of each type of procedure has an important implications.
With the rapid development of spinal endoscopic techniques, Endo-P/TLIF has been gradually used for the treatment of lumbar spondylolisthesis, which integrates endoscopic techniques, access techniques and percutaneous screw techniques, and performs intradural decompression and interbody implant fusion in a more direct and effective manner by combining the technical features of Endo-PLIF and Endo-TLIF [20].Endo-P/TLIF is comparable to the classical posterior lumbar interbody fusion (PLIF) [21–22], the location of the surgical access is more medial, mainly located in the inferior articular process of the superior vertebral body or close to the vertebral plate, which allows full intraoperative visualization of the entire nerve root and dural sac structures, and even decompression of the contralateral spinal canal can be achieved. In addition, minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is also a minimally invasive surgical procedure for the treatment of lumbar spondylolisthesis, which is mainly performed with the assistance of the Quadrant Spine Minimally Invasive Access System to perform interbody fusion and restoration, which is able to maximize the protection of the muscles and avoid the muscle from being stripped off in a large area, but its shortcomings are that it will cause a certain degree of pressure on the surrounding muscles, and it requires the constant processing of the slips from the The shortcoming of this is that it puts some pressure on the surrounding muscles and requires constant handling of the muscle that slips out of the gap and bottom of the dilatation plate to ensure a clear view. Endoscopic lumbar interbody fusion (Endo - LIF) is relatively less traumatic than MIS - TLIF because the intraoperative access and surgical wound for interbody implant fusion is relatively small, and the operation related to the surgery can be accomplished with the assistance of a spinal endoscope, and there is no need to deal with the slipped muscles, and it avoids the occurrence of extrusion of the surrounding soft tissues. One researcher [23] compared the clinical efficacy of Endo-LIF, MIS-TLIF, and open transforaminal lumbar interbody fusion (OTLIF) for the treatment of lumbar degenerative diseases through a retrospective meta-analysis, and found that Endo-LIF was able to effectively reduce the amount of intraoperative bleeding and the length of hospitalization compared to MIS-TLIF and OTLIF among the three different procedures. It was found that among the three different surgeries, Endo-LIF could effectively reduce the amount of intraoperative bleeding and hospitalization time, and reduce the incidence of back pain VAS scores and postoperative complications compared with MIS-TLIF and OTLIF, and that the long-term efficacy of Endo-LIF could reach the same level as OTLIF.Kou et al [24] meta-analyzed the inclusion of six articles of Endo-LIF versus MIS-TLIF in the treatment of lumbar degenerative diseases. LIF has significant advantages in reducing paraspinal muscle destruction and accelerating postoperative recovery, despite the longer operative time and relatively steep learning curve of LIF.Son et al [25] also compared the clinical efficacy of Endo-LIF with MIS -TLIF in the treatment of lumbar degenerative diseases in a meta-analysis, and the final results showed that the Endo-LIF procedure was less invasive, with less intra-operative bleeding, and was associated with lower back pain VAS scores. It is more advantageous in reducing patients' back pain VAS scores, and postoperative recovery is faster, but it has a longer operative time and a steeper learning curve.
In this study, we found that 21 patients with II lumbar spondylolisthesis treated by Endo - P/TLIF observed a significant increase in the intervertebral space height after surgery, as well as a significant increase in the lumbar anterior convexity angle and the anterior convexity angle of the operated segments compared to the preoperative period, and these differences were statistically significant (p < 0.05). Over time, the patients' VAS scores and ODI indices showed significant decreases at 1 month postoperatively, 6 months postoperatively, 12 months postoperatively, and at the final follow-up, and these differences were also statistically significant (p < 0.05). In addition, the rate of lumbar spondylolisthesis was significantly improved in all patients compared with the preoperative period (p < 0.05), and the lumbar fusion rate reached 85.7%. At the final follow-up, the modified MacNab score showed an excellent rate of 80.9%. In terms of postoperative complications, the incidence rate was 9.5%, in which one patient developed asymptomatic cerebrospinal fluid leakage, and the patient recovered normally after treatment; the other patient developed symptoms of neurologic heel irritation, and the patient recovered well after dehydration, nutritive neurologic and hormonal treatments. These results indicate that Endo-P/TLIF has significant clinical effects on improving the intervertebral space structure, reducing pain and improving the quality of life in the treatment of patients with II lumbar spondylolisthesis.
We believe that Endo-P/TLIF, as a minimally invasive surgical technique for the treatment of lumbar spondylolisthesis, can achieve smaller incisions and less tissue damage with the assistance of spinal endoscopy, which can help to reduce surgical trauma and postoperative pain, and to promote early recovery of patients. The selection and implementation of fusion techniques also have an impact on treatment outcomes, including the selection of implant material, determination of implant location, and evaluation of the degree of fusion. In terms of restoring lumbar stability, Endo-P/TLIF can protect the attachment of intervertebral muscles, small joint capsules and ligaments, and at the same time can implant bone grafting materials in the disc cavity to create a fusion environment and promote intervertebral bony fusion, which effectively restores lumbar stability, reduces lumbar pain symptoms and improves lumbar spine mobility. For patients with lumbar spondylolisthesis, nerve root compression leading to radiating pain in both lower limbs is a common concomitant symptom. Endo-P/TLIF achieves direct nerve decompression similar to that of traditional open surgery through visualization and a safer method, reducing the degree of slippage and correcting the abnormal displacement, thus relieving the compression on the nerve roots. In addition, patient postoperative recovery and complication rate are also important factors affecting the clinical efficacy of Endo-P/TLIF for the treatment of II lumbar spondylolisthesis. Because this procedure uses minimally invasive muscle dissection, with little damage to connective tissues and without excessive muscle resection, the patient's postoperative wound healing is good, and the incidence of incisional infections is relatively low, and the risk of deep vein thrombosis or pulmonary embolism is reduced, which effectively reduces the patient's postoperative risk of deep venous thrombosis or pulmonary embolism. The clinical observation of Endo-P/TLIF in the treatment of lumbar spondylolisthesis has made certain achievements, but there are still some shortcomings, the complexity and technical difficulty of the operation are high, which may lead to an increase in the risk of surgery when the operator is inexperienced, and affect the safety of the operation. Secondly, a more comprehensive study on the individual differences of patients and the applicability of different pathology types is still needed to ensure the individualization and relevance of the surgical plan.