Hybrid Interlaminar Endoscopic Lumbar Decompression in Disc Herniation Combined With Spinal Stenosis

Endoscopic transfacet Decompression for Severe Lumbar Spinal Stenosis: A Technical Note, Illustrative Clinical Series, and Surgeon Survey Regarding Post-Decompression Instability

Background: Lumbar spinal stenosis (LSS) remains a predominant cause of debilitating back and leg pain, affecting many aging populations. Traditional decompression surgeries can be invasive and pose significant risks and recovery time. This study elucidates the techniques and preliminary outcomes of endoscopic transfacet decompression in treating severe LSS. Methods: A retrospective review was performed on 65 patients with severe LSS who underwent endoscopic transfacet decompression. The patient outcomes were analyzed using the VAS for leg pain and the modified Macnab criteria. Pre-operative and post-operative scores were compared, and any complications were analyzed. An online survey was administered to 868 surgeons using Likert-scale ratings to evaluate surgeons' experience with endoscopic decompression in patients with painful spondylolisthesis. The survey responses were analyzed using descriptive statistics and Polytomous Rasch analysis to evaluate surgeon endorsement. Results: The study included 65 patients, of which 29 (44.6%) were female and 36 (55.4%) were male, with a mean age of 65.79 ranging from 38 to 84 years. The available mean post-operative follow-up period was 31.44 months, ranging from 24 to 39 months. The VAS score for leg pain reduced significantly from pre-operative 7.54 ± 1.67 to 2.20 ± 1.45 by 5.34 ± 2.03 (p < 0.001) with a large effect size (Cohen's d = 2.626). At the final follow-up, functional Macnab outcomes were reported as excellent by 20 (30.8%), good by 37 (56.9%), fair by 5 (7.7%), and poor by 3 (4.6%) of patients. There were no incidental durotomies, nerve root injuries, wound complications, or instances of post-operative instability. Only five patients (7.7%) developed post-operative dysesthesia. Incomplete decompression led to fair and poor outcomes in 8 (12.3%) patients. No revision surgeries were performed. post-operative instability was not observed. The surgeon survey corroborated these observations, where the polytomous Rasch analysis showed consensus on the effectiveness of the percutaneous endoscopic decompression of low-grade spondylolisthesis. Differential item functioning (DIF) analysis showed no significant bias in item responses between orthopaedic and neurosurgeons. Conclusions: The endoscopic transfacet decompression technique delineated herein showcased excellent Macnab outcomes in managing severe LSS, with a combined success rate of 87.7%. Patients also experienced a statistically significant reduction in leg pain. Dysesthesia rates were lower than with the transforaminal approach, likely because of limited exiting and traversing nerve root manipulation. This technique might represent a viable, less invasive alternative to open microsurgical dissection and decompression for patients with severe LSS, where fusion may be required. This approach was found to be highly accepted among endoscopic spine surgeons.

Full-Endoscopic Posterior Lumbar Interbody Fusion: A Review and Technical Note

Remarkable innovations in spinal endoscopic surgery have broadened its applications over the past 20 years. Full-endoscopic fusions have been widely reported, and several full-endoscopic approaches for interbody fusion have been published. In general, full-endoscopic lumbar interbody fusion (LIF) is called Endo-LIF, and facet-preserving Endo-LIF through the transforaminal route is called trans-Kambin's triangle LIF, which has a relatively longer history than facet-sacrificing Endo-LIF via the posterolateral route. Both approaches can reduce intraoperative and postoperative bleeding. However, there is a higher risk of subsidence and exit nerve root injury. There is no direct decompression in either of the interbody fusions, and additional decompression is required if there is severe lumbar bony canal stenosis. However, the posterior interlaminar approach, which is a well-known standard in full-endoscopic spine surgery, has rarely been applied in the field of endoscopic lumbar fusion surgery. Full-endoscopic posterior LIF (FE-PLIF) via an interlaminar approach can accomplish direct decompression of bony canal stenosis and safe interbody fusion. FE-PLIF via an interlaminar approach demonstrated a longer operation time, less blood loss, and shorter hospitalization duration than minimally invasive transforaminal LIF. FE-PLIF, which can accomplish direct decompression for bony spinal canal stenosis, is superior to other Endo-LIFs. However, FE-PLIF requires technical dexterity to improve efficiency and reduce technical complexity.

The Impact of Preoperative Adaptive Training on Postoperative Outcomes in Lumbar Spine Fusion Surgery for Lumbar Disc Herniation: A Retrospective Analysis

Purpose

Lumbar disc herniation, often treated with surgical decompression when conservative measures fail, presents challenges due to prolonged prone positioning in surgeries. This retrospective study evaluates the benefits of preoperative adaptive training to mitigate post-surgical physiological changes.

Patients and Methods

A review of medical records from June 2021 to March 2023 identified 170 patients unresponsive to conservative treatments. Grouped into adaptive training and control groups based on historical data, the former had undergone exercises to prepare for surgery and postoperative changes. Vital signs and VAS scores were extracted from patient records to assess training impact.

Results

The adaptive training group demonstrated stabilized vital signs intraoperatively, with a notable improvement in surgical exposure compared to the control group. However, there were no significant differences in operative time or blood loss between the groups. Additionally, postoperative VAS scores showed no significant improvement in the adaptive training group at follow-up intervals of 14 days, 1 month, and 3 months post-operation, compared to the control group.

Conclusion

Our study reveals that preoperative adaptive training stabilizes intraoperative blood pressure fluctuations in lumbar disc herniation surgeries. However, this stabilization does not significantly impact long-term postoperative pain management. This highlights the need for further research to explore comprehensive strategies that effectively combine preoperative training with postoperative care.

Full-Endoscopic Lumbar Discectomy Approach Selection: A Systematic Review and Proposed Algorithm

STUDY DESIGN

A systematic review of the literature to develop an algorithm formulated by key opinion leaders.

OBJECTIVE

This study aimed to analyze currently available data and propose a decision-making algorithm for full-endoscopic lumbar discectomy for treating lumbar disc herniation (LDH) to help surgeons choose the most appropriate approach [transforaminal endoscopic lumbar discectomy (TELD) or interlaminar endoscopic lumbar discectomy (IELD)] for patients.

SUMMARY OF BACKGROUND DATA

Full-endoscopic discectomy has gained popularity in recent decades. To our knowledge, an algorithm for choosing the proper surgical approach has never been proposed.

MATERIALS AND METHODS

A systematic review of the literature using PubMed and MeSH terms was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Patient samples included patients with LDH treated with full-endoscopic discectomy. The inclusion criteria were interventional research (randomized and nonrandomized trials) and observation research (cohort, case-control, case series). Exclusion criteria were case series and technical reports. The criteria used for selecting patients were grouped and analyzed. Then, an algorithm was generated based on these findings with support and reconfirmation from key expert opinions. Data on overall complications were collected. Outcome measures included zone of herniation, level of herniation, and approach (TELD or IELD).

RESULTS

In total, 474 articles met the initial screening criteria. The detailed analysis identified the 80 best-matching articles; after applying the inclusion and exclusion criteria, 53 articles remained for this review.

CONCLUSIONS

The proposed algorithm suggests a TELD for LDH located in the foraminal or extraforaminal zones at upper and lower levels and for central and subarticular discs at the upper levels considering the anatomic foraminal features and the craniocaudal pathology location. An IELD is preferred for LDH in the central or subarticular zones at L4/L5 and L5/S1, especially if a high iliac crest or high-grade migration is found.

Current Indications for Spinal Endoscopic Surgery and Potential for Future Expansion

Endoscopic spine surgery (ESS) has evolved as a safe, effective, and efficient alternative for minimally invasive spine surgery (MISS). The innovation of full-endoscopic systems makes definitive decompression surgery through different approaches feasible. The approach can be determined according to the location of the target lesion or the surgeon's preference. During the past 2 decades, ESS has expanded its indications from lumbar to cervical spines. Except for decompression, endoscopy-assisted fusion surgery is also developing. However, ESS is still evolving and has a steep learning curve. The revolution of technologies and ESS techniques will enable surgeons to treat various spinal diseases more practically. In recent years, the application of the computer-assisted navigation system and augmented reality have reformed imaging quality and interpretation. The endoscopic rhizotomy techniques have opened a new way for MISS of chronic low back pain. This review introduces the current indications of ESS and its potential future expansion.

Clinical Consequences of Incidental Durotomy during Full-Endoscopic Lumbar Decompression Surgery in Relation to Intraoperative Epidural Pressure Measurements

Background: Seizures, neurological deficits, bradycardia, and, in the worst cases, cardiac arrest may occur following incidental durotomy during routine lumbar endoscopy. Therefore, we set out to measure the intraoperative epidural pressure during lumbar endoscopic decompression surgery. Methods: We conducted a retrospective observational cohort study to obtain intraoperative epidural measurements with an epidural catheter-pressure transducer assembly through the spinal endoscope on 15 patients who underwent lumbar endoscopic decompression of symptomatic lumbar herniated discs and spinal stenosis. The endoscopic interlaminar technique was employed. Results: There were six (40.0%) female and nine (60.0%) male patients aged 49.0667 ± 11.31034, ranging from 36 to 72 years, with an average follow-up of 35.15 ± 12.48 months. Three of the fifteen patients had seizures with durotomy and one of these three had intracranial air on their postoperative brain CT. Another patient developed spinal headaches and diplopia on postoperative day one when her deteriorating neurological function was investigated with a brain computed tomography (CT) scan, showing an intraventricular hemorrhage consistent with a Fisher Grade IV subarachnoid hemorrhage. A CT angiogram did not show any abnormalities. Pressure recordings in the epidural space in nine patients ranged from 20 to 29 mm Hg with a mean of 24.33 mm Hg. Conclusion: Most incidental durotomies encountered during lumbar interlaminar endoscopy can be managed without formal repair and supportive care measures. The intradural spread of irrigation fluid and intraoperatively used drugs and air entrapment through an unrecognized durotomy should be suspected if patients deteriorate in the recovery room. Ascending paralysis may cause nausea, vomiting, upper and lower motor neuron symptoms, cranial nerve palsies, hypotension, bradycardia, and respiratory and cardiac arrest. The recovery team should be prepared to manage these complications.

Fully Endoscopic 360° Decompression for Central Lumbar Spinal Stenosis Combined with Disc Herniation: Technical Note and Preliminary Outcomes of 39 Cases

Purpose

To evaluate the outcomes, feasibility, and safety of endoscopic unilateral laminectomy, bilateral decompression and discectomy (Endo-ULBDD) for central lumbar spinal stenosis (CLSS) combined with disc herniation (DH).

Methods

This study includes 39 patients diagnosed with CLSS combined with DH who met the inclusion criteria and underwent surgery for Endo-ULBDD from April 2020 to March 2021. The mean age of the patients, operation time, hospitalization time, time in bed, and complications were recorded. Patients were followed up for at least 12 months. Visual analog scale (VAS) scores for low-back and lower-limb pain and Oswestry Disability Index (ODI) scores were evaluated preoperatively, before discharge, and at 3, 6, and 12 months postoperatively. To evaluate clinical effectiveness 12 months postoperatively, the modified MacNab criteria were used.

Results

The mean age of the patients was 59.9 years, the mean operation time was 82.1 minutes, the mean hospitalization time was 3.7 days, and the mean time in bed was 20.9 hours. The mean VAS scores of low-back and lower-limb pain improved from 5.9 and 7.2 to 2.0 and 1.6, respectively (P < 0.05). The ODI score improved from 56.0 to 16.7 (P < 0.05). The overall excellent-good rate of the modified MacNab criteria was 89.7%. Two kinds of complications occurred in 4 patients (10.3%), including 1 patient whose inferior articular process was excessively removed and 3 patients who suffered from postoperative dysesthesia. No other severe complications were noted.

Conclusion

Endo-ULBDD is a safe, feasible, efficient, and minimally invasive approach to treating CLSS combined with DH.

Comparative study of the efficacy and safety of minimally invasive interlaminar full-endoscopic discectomy versus conventional microscopic discectomy in single-level lumbar herniated intervertebral disc (ENDO-F Trial): a multicenter, prospective, randomized controlled trial protocol

Background

Advances in minimally invasive surgery have expanded the indications for interlaminar full-endoscopic discectomy. Although the clinical outcomes for this approach may be equivalent to those of conventional microscopic discectomy, the supporting evidence is still based on small, single-center, prospective, and retrospective studies. Therefore, a multicenter randomized controlled trial is warranted.

Methods

This will be a prospective, multicenter, randomized controlled trial comparing the efficacy and safety of interlaminar full-endoscopic discectomy to those of conventional microscopic discectomy. The trial will enroll 100 participants with a lumbar disc herniation, 50 in each group. The primary outcome will be the Oswestry Disability Index (ODI) score at 12 months post-surgery. Secondary outcomes will be back and leg pain (visual analog scale); the ODI; the EuroQol-5-dimension score; patient satisfaction; and walking distance/time and time to return to daily activities post-surgery. Surgical outcomes will include postoperative drainage, operative time, duration of hospital stay, postoperative creatine kinase level as an indicator of muscle injury, and postoperative scarring. Postoperative magnetic resonance imaging, computed tomography, and simple radiography will be performed to evaluate radiographic outcomes between the two surgical approaches. Surgery-related complications and adverse effects will be evaluated as safety outcomes. A single assessor at each participating hospital, blinded to group allocation, will assess the enrolled participants at baseline, at 2 weeks, and at 3, 6, and 12 months postoperatively.

Discussion

This trial is designed to determine whether interlaminar full-endoscopic discectomy is clinically comparable to microscopic discectomy to treat lumbar disc herniations. All efforts will be made to reduce bias, including adequate sample size, blinded analyses, and multicenter prospective registration. The outcomes will inform practice, providing the evidence needed for using interlaminar full-endoscopic over microscopic discectomy by confirming the potential of this technique to improve patient satisfaction and clinical outcomes.

Trial registration: Clinical Research Information Service; cris.nih.go.kr. (KCT0006277); protocol version (v1, June 8, 2021).