The benefit zone of full-endoscopic spine surgery

Treatment Concept and Technical Considerations of Biportal Endoscopic Spine Surgery for Lumbar Spinal Stenosis

Decompression is a major component of surgical procedures for degenerative lumbar spinal stenosis (LSS). In addition to sufficient decompression to guarantee the relief of neurological pain, compensating surgical instability after wider laminectomy and foraminotomy and instrumentation with caging and fusion with grafting are performed to secure or restore the foraminal dimension and correct coronal/sagittal imbalance for longer survival of the adjacent segment. Endoscopic spinal surgery (ESS) has been developed under the flag of successful decompression while preserving structural integrity as much as possible with the help of magnification and illumination. ESS provides a technical possibility and feasibility for solving LSS by decompression alone. Recently, many endoscopic trials have been conducted to overcome conventional surgical treatment that requires wider dissection, escape inevitable complications from surgical damage, and compensate for the fusion technique. However, biportal ESS has some technical limitations, including clinical difficulties in accessibility for more moderate to severe stenosis and challenges for complicated conditions with segmental ventral slip, isthmic defect, stenosis combined with foraminal stenosis or foraminal disk rupture, or degenerative segmental scoliosis with disk height collapsing and endplate fatigue fracture. Because decompression alone is a skill for eliminating pathologies, there is no function of preserving degenerative structure or stopping the recurrence of disk degeneration or subsidence. This review of clinical reports investigated the possibility of biportal ESS for treating degenerative lumbar disorders by sufficient decompression and adequate elimination of various pathologies and decreasing technical complications. The results of this study may help develop better innovative spinal surgical techniques in the near future.

Advances and Challenges of Endoscopic Spine Surgery

The purpose of this paper is to review the data supporting current endoscopic surgical techniques for the spine and the potential challenges and future of the field. The origins of endoscopic spine surgery can be traced back many decades, with many important innovations throughout its development. It can be applied to all levels of the spine, with many robust trials supporting its clinical outcomes. Continued clinical research is needed to explore its expanding indications. Although the limitations of starting an endoscopic program can be justified by its cost effectiveness and positive societal impact, challenges facing its widespread adoption are still present. As more residency and fellowship programs include endoscopy as part of their spine training, it will become more prevalent in hospitals in the United States. Technological advancements in spine surgery will further propel and enhance endoscopic techniques as they become an integral part of a spine surgeon's repertoire.

Smartphone applications for remote patient monitoring reduces clinic utilization after full-endoscopic spine surgery

INTRODUCTION

The rising number of outpatient spine surgeries creates challenges in postoperative management and care. Telemedicine offers a unique opportunity to reduce in-person clinic visits and improve resource allocation. We aimed to investigate the impact of a validated smartphone application on clinic utilization following full-endoscopic spine surgery (FESS).

METHODS

We evaluated patients undergoing FESS from 2020 to 2022 and a pre-COVID control group (CG) from 2018 to 2019. Subsequently, we divided the patients into three groups: one using the application (intervention group, IG), and two CGs (2020-2022, CG and 2018-2019, historical control group (HG)). We analyzed the post-surgical hospitalization rate, all follow-ups, and virtually transmitted patient-reported outcomes.

RESULTS

A total of 115 patients were included in the IG. The CG consisted of 137 and the HG of 202 patients (CG and HG in the following). Group homogeneity was satisfactory regarding patient age (p = 0.9), sex (p = 0.88), and body mass index (p = 0.99). IG patients were treated as outpatients significantly more often [14.78% vs. 29.2% vs. 37.62% (p < 0.001)]. Additionally, IG patients showed significantly higher follow-up compliance [74.78% vs. 40.14% vs. 37.13% (p < 0.001)] 3-month post-surgery and fewer in-patient follow-up visits [(0.5 ± 0.85 vs. 1.32 ± 0.8 vs. 1.33 ± 0.7 (p < 0.001)].

CONCLUSION

Our results underline the feasibility, efficacy, and safety of remote patient monitoring following FESS. Furthermore, they highlight the opportunity to implement a virtual wound checkup, and to substantially improve postoperative follow-up compliance via telemedicine.

The Evolution of Spinal Endoscopy: Design and Image Analysis of a Single-Use Digital Endoscope Versus Traditional Optic Endoscope

Spinal endoscopy has evolved significantly since its inception, offering minimally invasive solutions for various spinal pathologies. This study introduces a promising innovation in spinal endoscopy-a single-use digital endoscope designed to overcome the drawbacks of traditional optic endoscopes. Traditional endoscopes, despite their utility, present challenges such as fragility, complex disinfection processes, weight issues, and susceptibility to mechanical malfunctions. The digital endoscope, with its disposable nature, lighter weight, and improved image quality, aims to enhance surgical procedures and patient safety. The digital endoscope system comprises a 30-degree 1000 × 1000 pixel resolution camera sensor with a 4.3 mm working channel, and LED light sources replacing optical fibers. The all-in-one touch screen tablet serves as the host computer, providing portability and simplified operation. Image comparisons between the digital and optic endoscopes revealed advantages in the form of increased field of view, lesser distortion, greater close-range resolution, and enhanced luminance. The single-use digital endoscope demonstrates great potential for revolutionizing spine endoscopic surgeries, offering convenience, safety, and superior imaging capabilities compared to traditional optic endoscopes.

Australian Spine Surgeon's Perspectives on Endoscopic Spine Surgery: An In-depth Analysis

OBJECTIVE

Endoscopic spine surgery (ESS) is a minimally invasive approach with reduced tissue trauma, shorter hospital stays, and faster recovery times. It employs advanced endoscopic instruments and imaging technologies to address a wide range of spinal pathologies with minimal disruption to surrounding tissues. As ESS continues to evolve, this article aims to gather insights into the opinions and perspectives of the key stakeholders involved, and highlight strategies to improve implementation.

METHODS

A cross-sectional survey was distributed to collect data on Australian spine surgeons' perspectives of ESS. The survey questionnaire was distributed electronically to a diverse group of spine surgeons who are members of the Spine Society of Australia.

RESULTS

Of responders, 46.8% were already integrating ESS into practice, or had the sufficient training to commence ESS. A further 29.8% were contemplating introduction of ESS techniques, while just under one quarter of respondents (23.4%) were not interested in implementing minimally invasive techniques. Primary motivators for implementation included skill development and improved patient outcomes. Primary barriers included lack of training opportunities, length of time to develop competency and lack of current supporting evidence.

CONCLUSION

The study contributes to the existing body of knowledge on ESS by providing a comprehensive analysis of surgeon opinions and experiences. The results highlight the growing interest in endoscopic techniques, while recognizing the challenges that need to be addressed to make this more widely utilised and available. The findings can guide future research, training programs, clinical practice and ultimately improve health and financial outcomes to patients and the wider health system.

The Endoscopic Lumbar Interbody Fusion: A Narrative Review, and Future Perspective

Lumbar interbody fusion stands as a preferred surgical solution for degenerative lumbar spine diseases. The procedure primarily aims to establish lumbar segment stability, directly addressing patient symptoms associated with spinal complications. Traditional open surgery, though effective, is linked with notable morbidities and extended recovery time. To mitigate these concerns, minimally invasive surgery (MIS) has garnered significant popularity, presenting an appealing alternative with numerous benefits such as reduced soft tissue trauma, decreased blood loss, and expedited recovery. Among MIS procedures, full endoscopic spinal surgery, characterized by its minimal invasiveness, holds the potential to further minimize morbidities while enhancing surgical outcomes. Endoscopic lumbar interbody fusion, a novel procedure within this paradigm, has gained attention for offering advantages comparable to those of minimally invasive transforaminal lumbar interbody fusion. However, the safety, efficacy, and associated surgical techniques and instrument design of this method continue to be subjects of ongoing debate. This paper critically reviews current evidence on the safety, efficacy, and advantages of endoscopic lumbar spinal interbody fusion, examining whether it could indeed supersede existing mainstream techniques.

Interlaminar Endoscopic Lumbar Discectomy Versus Microscopic Lumbar Discectomy: A Preliminary Analysis of L5-S1 Lumbar Disc Herniation Outcomes in Prospective Randomized Controlled Trials

OBJECTIVE

A preliminary report from a single institution, noninferiority, prospective randomized controlled trial is conducted to determine the effectiveness of interlaminar endoscopic lumbar discectomy (IELD) versus microscopic lumbar discectomy (MLD) for the treatment of L5-S1 lumbar disc herniation (LDH).

METHODS

This prospective, noncrossover, randomized controlled trials was conducted at a single neurosurgical center. Patients with symptomatic radiculopathy or intermittent neurogenic claudication caused by LDH were enrolled from July 2016 to July 2021. The study compared the effectiveness of microscopic and full-endoscopic discectomy procedures. Outcome measures included visual analogue scale (VAS) scores for back and leg pain, Oswestry Disability Index scores, radiologic measurements, endurance time of walking, and satisfaction rate.

RESULTS

Of 37 assessed patients, both IELD and MLD groups demonstrated significant improvements in VAS scores for pain over time, with no significant difference between them. For secondary outcomes, the IELD group had a shorter hospital stay and reduced blood loss but a longer operation time than the MLD group. Radiographic evaluations showed no change compared to preoperative data. Patient satisfaction and recovery rates were slightly higher for the MLD group, but both groups were comparable in most evaluations, with complications being minimal.

CONCLUSION

The IELD was noninferior in improving the intensity of back and leg pain and functional disability, compared to the MLD. Additionally, the IELD showed no difference in clinical outcomes for patients in terms of radiographic results and patient satisfaction rates. The results of this research preliminarily demonstrate that the IELD could be considered an effective alternative to MLD for L5-S1 central or paracentral LDH.

Combined endoscopic and microsurgical approach for the drainage of a multisegmental thoracolumbar epidural abscess: illustrative case

BACKGROUND

Spinal epidural abscess is a rare but serious infectious disease that can rapidly develop into a life-threatening condition. Therefore, the appropriate treatment is indispensable. Although conservative treatment is justifiable in certain cases, surgical treatment needs to be considered as an alternative early on because of complications such as (progressive) neurological deficits or sepsis. However, traditional surgical techniques usually include destructive approaches up to (multilevel) laminectomies. Such excessive approaches do have biomechanical effects potentially affecting the long-term outcomes. Therefore, minimally invasive approaches have been described as alternative strategies, including endoscopic approaches.

OBSERVATIONS

The authors describe a surgical technique involving a combination of two minimally invasive approaches (endoscopic and microsurgical) to drain a multisegmental (thoracolumbar) abscess using the physical phenomenon of continuous pressure difference to minimize collateral tissue damage.

LESSONS

The combination of minimally invasive approaches, including the endoscopic technique, may be an alternative in draining selected epidural abscesses while achieving a similar amount of abscess removal and causing less collateral approach damage in comparison with more traditional techniques.

Comparison of full-endoscopic and tubular-based microscopic decompression in patients with lumbar spinal stenosis: a randomized controlled trial

PURPOSE

We aimed to demonstrate non-inferiority in terms of functional outcomes in patients with lumbar spinal stenosis who underwent full-endoscopic decompression compared with tubular-based microscopic decompression.

METHODS

This prospective, randomized controlled, non-inferiority trial included 60 patients with single-level lumbar spinal stenosis who required decompression surgery. The patients were randomly assigned in a 1:1 ratio to the full-endoscopic group (FE group) or the tubular-based microscopic group (TM group). Based on intention-to-treat analysis, the primary outcome was the Oswestry Disability Index score at 24 months postoperative. The secondary outcomes included the visual analog scale (VAS) score for back and leg pain, European Quality of Life-5 Dimensions (EQ-5D) score, walking time, and patient satisfaction rate according to the modified MacNab criteria. Surgery-related outcomes were also analyzed.

RESULTS

Of the total patients, 92% (n = 55) completed a 24-month follow-up. The primary outcomes were comparable between the two groups (p = 0.748). However, the FE group showed a statistically significant improvement in the mean VAS score for back pain at day 1 and at 6, 12, and 24 months after surgery (p < 0.05). No significant difference was observed in the VAS score for leg pain, EQ-5D score, or walking time (p > 0.05). Regarding the modified MacNab criteria, 86.7% of patients in the FE group and 83.3% in the TM group had excellent or good results at 24 months after surgery (p = 0.261). Despite the similar results in surgery-related outcomes, including operative time, radiation exposure, revision rate, and complication rate, between the two groups (p > 0.05), less blood loss and shorter length of hospital stay were observed in the FE group (p ≤ 0.001 and 0.011, respectively).

CONCLUSION

This study suggests that full-endoscopic decompression is an alternative treatment for patients with lumbar spinal stenosis because it provides non-inferior clinical efficacy and safety compared with tubular-based microscopic surgery. In addition, it offers advantages in terms of less invasive surgery. Trial registration number (TRN): TCTR20191217001.

Incidence and management of dural tears in full-endoscopic unilateral laminotomies for bilateral lumbar decompression

PURPOSE

To report incidence of dural lacerations in lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD) and to describe patient outcomes following a novel full-endoscopic bimanual durotomy repair.

METHODS

Retrospective review of prospectively collected database including 5.5 years of single surgeon experience with LE-ULBD. Patients with no durotomy were compared with patients who experienced intraoperative durotomy, including demographics, ASA score, prior surgery, number of levels treated, procedure time, hospital length of stay (LOS), visual analogue scale, perioperative complications, revision surgeries, use of analgesics, and Oswestry Disability Index (ODI).

RESULTS

In total, 13/174 patients (7.5%) undergoing LE-ULBD experienced intraoperative durotomy. No significant differences in demographic, clinical or operative variables were identified between the 2 groups. Sustaining a durotomy increased LOS (p = 0.0019); no differences in perioperative complications or rate of revision surgery were identified. There was no difference in minimally clinically important difference for ODI between groups (65.6% for no durotomy versus 55.6% for durotomy, p = 0.54).

CONCLUSION

In this cohort, sustaining a durotomy increased LOS but, with accompanying intraoperative repair, did not significantly affect rate of complications, revision surgery or functional outcomes. Our method of bimanual endoscopic dural repair provides an effective approach for repair of dural lacerations in interlaminar ULBD cases.

Full endoscopic spine surgery

Background

With a dramatic increase in elderly population worldwide, the prevalence of degenerative spine disease is steadily rising. Even though the entire spinal column is affected the problem is more commonly seen in the lumbar, cervical spine and to some extent the thoracic spine. The treatment of symptomatic lumbar disc or stenosis is primarily conservative with analgesics, epidural steroids and physiotherapy. Surgery is advised only if conservative treatment is ineffective. Conventional open microscopic procedures even though are still a gold standard, have the disadvantages of excessive muscle damage and bone resection, epidural scarring along with prolonged hospital stay and increased need of postoperative analgesics. Minimal access spine surgeries minimize surgical access related injury by minimizing soft tissue and muscle damage and also bony resection thus preventing iatrogenic instability and unnecessary fusions. This leads to good functional preservation of the spine and enhances early postoperative recovery and early return to work. Full endoscopic spine surgeries are one of the more sophisticated and advanced form of MIS surgeries.

Purpose

Full endoscopy has definitive benefits over conventional microsurgical techniques. These include better and clear vision of the pathology due to presence of irrigation fluid channel, minimal soft tissue and bone trauma, better and relatively easy approach to deep seated pathologies like thoracic disc herniations and a possibility to avoid fusion surgeries. The purpose of this article is to describe these benefits, give an overview of the two main approaches - transforaminal and interlaminar, their indications, contraindications and their limitations. The article also describes about the challenges in overcoming the learning curve and its future prospectives.

Conclusion

Full endoscopic spine surgery is one of the fastest growing technique in the field of modern spine surgery. Better intraoperative visualization of the pathology, lesser incidence of complications, faster recovery time, less postoperative pain, better relief of symptoms and early return to activity are the main reasons behind this rapid growth. With better patient outcomes and reduced medical costs, the procedure is going to be more accepted, relevant and popular procedure in future.

Fully Endoscopic Spine Separation Surgery in Metastatic Disease-Case Series, Technical Notes, and Preliminary Findings

Objective: This report aims to describe the surgical methodology and potential effectiveness of endoscopic separation surgery (ESS) in patients with metastatic spine disease. This concept may reduce the invasiveness of the procedure, which can potentially speed up the wound healing process and, thus, the possibility of faster application of radiotherapy. Materials and Methods: In this study, separation surgery for preparing patients for stereotactic body radiotherapy (SBRT) was performed with fully endoscopic spine surgery (FESS) followed by percutaneous screw fixation (PSF). Results: Three patients with metastatic spine disease in the thoracic spine were treated with fully endoscopic spine separation surgery. The first case resulted in the progression of paresis symptoms that resulted in disqualification from further oncological treatment. The remaining two patients achieved satisfactory clinical and radiological effects and were referred for additional radiotherapy. Conclusions: With advancements in medical technology, such as endoscopic visualization, and new tools for coagulation, we can treat more and more spine diseases. Until now, spine metastasis was not an indication for the use of endoscopy. This method is very technically challenging and risky, especially at such an early stage of application, due to variations in the patient's condition, morphological diversity, and the nature of metastatic lesions in the spine. Further trials are needed to determine whether this new approach to treating patients with spine metastases is a promising breakthrough or a dead end.

Personalized Interventional Surgery of the Lumbar Spine: A Perspective on Minimally Invasive and Neuroendoscopic Decompression for Spinal Stenosis

Pain generator-based lumbar spinal decompression surgery is the backbone of modern spine care. In contrast to traditional image-based medical necessity criteria for spinal surgery, assessing the severity of neural element encroachment, instability, and deformity, staged management of common painful degenerative lumbar spine conditions is likely to be more durable and cost-effective. Targeting validated pain generators can be accomplished with simplified decompression procedures associated with lower perioperative complications and long-term revision rates. In this perspective article, the authors summarize the current concepts of successful management of spinal stenosis patients with modern transforaminal endoscopic and translaminar minimally invasive spinal surgery techniques. They represent the consensus statements of 14 international surgeon societies, who have worked in collaborative teams in an open peer-review model based on a systematic review of the existing literature and grading the strength of its clinical evidence. The authors found that personalized clinical care protocols for lumbar spinal stenosis rooted in validated pain generators can successfully treat most patients with sciatica-type back and leg pain including those who fail to meet traditional image-based medical necessity criteria for surgery since nearly half of the surgically treated pain generators are not shown on the preoperative MRI scan. Common pain generators in the lumbar spine include (a) an inflamed disc, (b) an inflamed nerve, (c) a hypervascular scar, (d) a hypertrophied superior articular process (SAP) and ligamentum flavum, (e) a tender capsule, (f) an impacting facet margin, (g) a superior foraminal facet osteophyte and cyst, (h) a superior foraminal ligament impingement, (i) a hidden shoulder osteophyte. The position of the key opinion authors of the perspective article is that further clinical research will continue to validate pain generator-based treatment protocols for lumbar spinal stenosis. The endoscopic technology platform enables spine surgeons to directly visualize pain generators, forming the basis for more simplified targeted surgical pain management therapies. Limitations of this care model are dictated by appropriate patient selection and mastering the learning curve of modern MIS procedures. Decompensated deformity and instability will likely continue to be treated with open corrective surgery. Vertically integrated outpatient spine care programs are the most suitable setting for executing such pain generator-focused programs.

Determination of Work Related to Endoscopic Decompression of Lumbar Spinal Stenosis

Background: Effective 1 January 2017, single-level endoscopic lumbar discectomy received a Category I Current Procedural Terminology (CPT®) code 62380. However, no work relative value units (wRVUs) are currently assigned to the procedure. A physician’s payment needs to be updated to commensurate with the work involved in the modern version of the lumbar endoscopic decompression procedure with and without the use of any implants to stabilize the spine. In the United States, the American Medical Association (AMA) and its Specialty Society Relative Value Scale Update Committee (RUC) proposes to the Centers for Medicare and Medicaid Services (CMS) what wRVUs to assign for any endoscopic lumbar surgery codes. Methods: The authors conducted an independent survey between May and June 2022 which reached 210 spine surgeons using the TypeForm survey platform. The survey link was sent to them via email and social media. Surgeons were asked to assess the endoscopic procedure’s technical and physical effort, risk, and overall intensity without focusing just on the time required to perform the surgery. Respondents were asked to compare the work involved in modern comprehensive endoscopic spine care with other commonly performed lumbar surgeries. For this purpose, respondents were provided with the verbatim descriptions of 12 other existing comparator CPT® codes and associated wRVUs of common spine surgeries, as well as a typical patient vignette describing an endoscopic lumbar decompression surgery scenario. Respondents were then asked to select the comparator CPT® code most reflective of the technical and physical effort, risk, intensity, and time spent on patient care during the pre-operative, peri- and intra-operative, and post-operative periods of a lumbar endoscopic surgery. Results: Of the 30 spine surgeons who completed the survey, 85.8%, 46.6%, and 14.3% valued the appropriate wRVU for the lumbar endoscopic decompression to be over 13, over 15, and over 20, respectively. Most surgeons (78.5%; <50th percentile) did not think they were adequately compensated. Regarding facility reimbursement, 77.3% of surgeons reported that their healthcare facility struggled to cover the cost with the received compensation. The majority (46.5%) said their facility received less than USD 2000, while another 10.7% reported less than USD 1500 and 17.9% reported less than USD 1000. The professional fee received by surgeons was <USD 1000 for 21.4%, <USD 2000 for 17.9%, and <USD 1500 for 10.7%, resulting in a fee less than USD 2000 for 50% of responding surgeons. Most responding surgeons (92.6%) recommended an endoscopic instrumentation carveout to pay for the added cost of the innovation. Discussion and Conclusions: The survey results indicate that most surgeons associate CPT® 62380 with the complexity and intensity of a laminectomy and interbody fusion preparation, considering the work in the epidural space using the contemporary outside-in and interlaminar technique and the work inside the interspace using the inside-out technique. Modern endoscopic spine surgery goes beyond the scope of a simple soft-tissue discectomy. The current iterations of the procedure must be considered to avoid undervaluing its complexity and intensity. Additional undervalued payment scenarios could be created if technological advances continue to replace traditional lumbar spinal fusion protocols with less burdensome, yet no less complex, endoscopic surgeries that necessitate a high surgeon effort in terms of time required to perform the operation and its intensity. These undervalued payment scenarios of physician practices, as well as the facility and malpractice expenses, should be further discussed to arrive at updated CPT® codes reflective of modern comprehensive endoscopic spine care.

Endoscopic and Nonendoscopic Approaches to Single-Level Lumbar Spine Decompression: Propensity Score-Matched Comparative Analysis and Frailty-Driven Predictive Model

Objective: The endoscopic spine surgery (ESS) approach is associated with high levels of patient satisfaction, shorter recovery time, and reduced complications. The present study reports multicenter, international data, comparing ESS and non-ESS approaches for singlelevel lumbar decompression, and proposes a frailty-driven predictive model for nonhome discharge (NHD) disposition.Methods: Cases of ESS and non-ESS lumbar spine decompression were queried from the American College of Surgeons National Surgical Quality Improvement Program database (2017–2020). Propensity score matching was performed on baseline characteristics frailty score (measured by risk analysis index [RAI] and modified frailty index-5 [mFI-5]). The primary outcome of interest was NHD disposition. A predictive model was built using logistic regression with RAI as the primary driver.Results: Single-level nonfusion spine lumbar decompression surgery was performed in 38,686 patients. Frailty, as measured by RAI, was a reliable predictor of NHD with excellent discriminatory accuracy in receiver operating characteristic (ROC) curve analysis: C-statistic: 0.80 (95% confidence interval [CI], 0.65–0.94) in ESS cohort, C-statistic: 0.75 (95% CI, 0.73–0.76) overall cohort. After propensity score matching, there was a reduction in total operative time (89 minutes vs. 103 minutes, p = 0.049) and hospital length of stay (LOS) (0.82 days vs. 1.37 days, p < 0.001) in patients treated endoscopically. In ROC curve analysis, the frailty-driven predictive model performed with excellent diagnostic accuracy for the primary outcome of NHD (C-statistic: 0.87; 95% CI, 0.85–0.88).Conclusion: After frailty-based propensity matching, ESS is associated with reduced operative time, shorter hospital LOS, and decreased NHD. The RAI frailty-driven model predicts NHD with excellent diagnostic accuracy and may be applied to preoperative decisionmaking with a user-friendly calculator: nsgyfrailtyoutcomeslab.shinyapps.io/lumbar_decompression_dischargedispo.

The effect of various options for decompression of degenerated lumbar spine motion segments on the range of motion: a biomechanical in vitro study

BACKGROUND

Lumbar spinal stenosis is a common disease in the aging population. Decompression surgery represents the treatment standard, however, a risk of segmental destabilization depending on the approach and extent of decompression is discussed. So far, biomechanical studies on techniques were mainly conducted on non-degenerated specimens. This biomechanical in vitro study aimed to investigate the increase in segmental range of motion (ROM) depending on the extent of decompression in degenerated segments.

METHODS

Ten fresh frozen lumbar specimens were embedded in polymethyl methacrylate (PMMA) and loaded in a spine tester with pure moments of ± 7.5 Nm. The specimens were tested in their intact state for lateral bending (LB), flexion/extension (FE) and axial rotation (AR). Subsequently, four different decompression techniques were performed: unilateral interlaminar decompression (DC1), unilateral with "over the top" decompression (DC2), bilateral interlaminar decompression (DC3) and laminectomy (DC4). The ROM of the index segment was reported as percent (%) of the native state.

RESULTS

Specimens were measured in their intact state prior to decompression. The mean ROM was defined as 100% (FE:6.3 ± 2.3°; LB:5.4 ± 2.8°; AR:3.0 ± 1.6°). Interventions showed a continuous ROM increase: FE (DC1: + 4% ± 4.3; DC2: + 4% ± 4.5; DC3: + 8% ± 8.3;DC4: + 20% ± 15.9), LB(DC1: + 4% ± 6.0; DC2: + 5% ± 7.3; DC3: + 8% ± 8.3; DC4: + 11% ± 9.9), AR (DC1: + 7% ± 6.0; DC2: + 9% ± 7.9; DC3: + 15% ± 11.5; DC4: + 19% ± 10.5). Significant increases in ROM for all motion directions (p < 0.05) were only obtained after complete laminectomy (DC4).

CONCLUSION

Unilateral and/or bilateral decompressive surgery resulted in a statistically insignificant ROM increase, whereas complete laminectomy showed statistically significant ROM increase. If this ROM increase also has an impact on the clinical outcome and how to identify segments at risk for secondary lumbar instability should be evaluated in further studies.

Full-endoscopic spine surgery diminishes surgical site infections - a propensity score-matched analysis

BACKGROUND CONTEXT

Surgical site infections (SSI) are one the most frequent and costly complications following spinal surgery. The SSI rates of different surgical approaches need to be analyzed to successfully minimize SSI occurrence.

PURPOSE

The purpose of this study was to define the rate of SSIs in patients undergoing full-endoscopic spine surgery (FESS) and then to compare this rate against a propensity score-matched cohort from the National Surgical Quality Improvement Program (NSQIP) database.

DESIGN

This is a retrospective multicenter cohort study using a propensity score-matched analysis of prospectively maintained databases.

PATIENT SAMPLE

One thousand two hundred seventy-seven non-instrumented FESS cases between 2015 and 2021 were selected for analysis. In the nonendoscopic NSQIP cohort we selected data of 55,882 patients.

OUTCOME MEASURES

The occurrence of any SSI was the primary outcome. We also collected any other perioperative complications, demographic data, comorbidities, operative details, history of smoking, and chronic steroid intake.

METHODS

All FESS cases from a multi-institutional group that underwent surgery from 2015 to 2021 were identified for analysis. A cohort of cases for comparison was identified from the NSQIP database using Current Procedural Terminology of nonendoscopic cervical, thoracic, and lumbar procedures from 2015 to 2019. Trauma cases as well as arthrodesis procedures, surgeries to treat pathologies affecting more than 4 levels or spine tumors that required surgical treatment were excluded. In addition, nonelective cases, and patients with wounds worse than class 1 were also not included. Patient demographics, comorbidities, and operative details were analyzed for propensity matching.

RESULTS

In the non-propensity-matched dataset, the endoscopic cohort had a significantly higher incidence of medical comorbidities. The SSI rates for nonendoscopic and endoscopic patients were 1.2% and 0.001%, respectively, in the nonpropensity match cohort (p-value <.011). Propensity score matching yielded 5936 nonendoscopic patients with excellent matching (standard mean difference of 0.007). The SSI rate in the matched population was 1.1%, compared to 0.001% in endoscopic patients with an odds ratio 0.063 (95% confidence interval (CI) 0.009-0.461, p=.006) favoring FESS.

CONCLUSIONS

FESS compares favorably for risk reduction in SSI following spinal decompression surgeries with similar operative characteristics. As a consequence, FESS may be considered the optimal strategy for minimizing SSI morbidity.

Full Endoscopic Ligamentum Flavum Sparing Unilateral Laminotomy for Bilateral Recess Decompression: Surgical Technique and Clinical Results

OBJECTIVE

Interlaminar endoscopic spine surgery has been introduced and utilized for lumbar lateral recess decompression. We modified this technique and utilized it for bilateral lateral recess stenoses without significant central stenosis. Here we present the surgical details and clinical outcome of ligamentum flavum sparing unilateral laminotomy for bilateral recess decompression (ULBRD).

METHODS

Prospectively collected registry for full-endoscopic surgeries was reviewed retrospectively. One hundred eighty-two consecutive cases from a single center between September 2015 and March 2021 were reviewed and 57 of them whom underwent ULBRD were enrolled for analysis. Basic patient demographic data, perioperative details, surgeryrelated complications, and clinical outcome were reviewed. The detailed surgical technique is presented as well.

RESULTS

Among the 57 patients enrolled, 37 were males while the other 20 were females. The mean age was 58.53 ± 14.51 years, and a bimodal age distribution at the age of mid-fifties and mid-sixties or older was noted. The later age-peak was related to coexistence of degenerative scoliosis. The average operative time per lamina was 70.34 ± 20.51 minutes and mean length of stay was 0.56 ± 0.85 days. Four perioperative complications were reported (7.0%) and the overall reoperation rate at the index level within 1 year was 8.8%. The preoperative back/leg visual analogue scale scores and functional outcome scales including EuroQol-5 dimension questionnaire, Oswestry Disability Index presented significant improvement immediately after surgery and were maintained until final follow-up.

CONCLUSION

ULBRD for bilateral lateral recess stenoses without significant central stenosis resulted in good clinical outcomes with acceptably low perioperative complications rates. Sufficient decompression was achieved with the central ligamentum flavum being preserved.

Clinical efficacy and learning curve of posterior percutaneous endoscopic cervical laminoforaminotomy for patients with cervical spondylotic radiculopathy

In this study, we aimed to investigate the clinical efficacy and learning curve of posterior percutaneous endoscopic cervical laminoforaminotomy (PPECLF) in patients with cervical spondylotic radiculopathy (CSR). A total of 64 patients with CSR received PPECLF. Clinical outcome scores included the visual analog scale, Japanese Orthopedic Association score, neck disability index, and modified Macnab criteria. Radiological outcomes included the disc height, C2 to C7 Cobb angle, and range of motion. The learning curve was evaluated using cumulative sum analysis. Patients were divided into accumulation phase and mastery phase groups (A and B), and general data and surgical efficacy were compared between the 2 groups. Follow-up ranged from 12 to 24 months. Clinical outcome scores improved significantly at the final follow-up, and there were no differences in radiological outcomes. Surgical efficacy was excellent and good in 82.8% of patients. The operative time showed a decreasing trend with the accumulation of cases. Patients were divided and the 26th case was the cutoff point according to the learning curve. No significant differences were found in the clinical outcomes between the 2 groups. Decompression with PPECLF was safe and effective in the treatment of CSR. With the accumulation of cases, the operative time was gradually shortened, and the clinical efficacy was significant. The PPECLF procedure can be performed efficiently and safely to treat CSR.

Percutaneous full-endoscopic uniportal decompression for the treatment of symptomatic idiopathic lumbar spinal epidural lipomatosis: Technical note

Background

Lumbar spinal epidural lipomatosis (SEL) is a rare condition characterized by an excessive accumulation of adipose tissue within the spinal canal, compressing the dura sac and/or nerve roots. When conservative treatments fail and clinical symptoms progress quickly and seriously, surgical decompression should be considered. With the rapid development of endoscopic armamentaria and techniques, the pathological scope that can be treated by percutaneous endoscopic spine surgery is ever expanding.

Objective

In this paper, the authors describe a patient with lumbar spinal epidural lipomatosis who was treated with a percutaneous full-endoscopic uniportal decompression surgery successfully. This article aims to validate the feasibility of percutaneous full-endoscopic uniportal decompression for the treatment of symptomatic idiopathic spinal epidural lipomatosis via interlaminar approach.

Methods

We describe a case of a 69-year-old man with a 10-year history of low back pain, intermittent claudication, and bilateral leg neuropathic pain. He was diagnosed with lumbar epidural lipomatosis, which did not respond to conservative therapy. After a comprehensive evaluation, he underwent percutaneous endoscopic spine surgery to remove hyperplastic adipose tissue and decompress nerve roots and dura sac.

Results

The patient was treated with a percutaneous full-endoscopic uniportal decompression surgery successfully. After the procedure, his leg pain decreased and his walking capacity improved. There were no surgery-related complications, such as cerebrospinal fluid leakage, incision infection, etc.

Conclusions

The case with SEL was successfully treated with a percutaneous full-endoscopic uniportal surgery, which has the advantages of excellent presentation of anatomical structures, expanded field of vision, less surgical-related trauma, and bleeding. The key point of the procedure is to release and cut off the bands which divide the epidural space into small rooms filled with excess adipose tissue.

Navigation Techniques in Endoscopic Spine Surgery

Endoscopic spine surgery (ESS) advances the principles of minimally invasive surgery, including minor collateral tissue damage, reduced blood loss, and faster recovery times. ESS allows for direct access to the spine through small incisions and direct visualization of spinal pathology via an endoscope. While this technique has many applications, there is a steep learning curve when adopting ESS into a surgeon's practice. Two types of navigation, optical and electromagnetic, may allow for widespread utilization of ESS by engendering improved orientation to surgical anatomy and reduced complication rates. The present review discusses these two available navigation technologies and their application in endoscopic procedures by providing case examples. Furthermore, we report on the future directions of navigation within the discipline of ESS.

Quality of conscious sedation using dexmedetomidine during full-endoscopic transforaminal discectomy for sciatica: a prospective case series

INTRODUCTION

Percutaneous transforaminal endoscopic discectomy (PTED) is increasing in popularity as a minimally invasive procedure to treat sciatica caused by lumbar disc herniation. The objective of the current study is to evaluate safety of and satisfaction with the use of local anesthesia and conscious sedation during PTED.

METHODS

During a 12-month inclusion period, patients were prospectively included in this single center case series. Inclusion criteria consisted of sciatica lasting for at least 6 weeks, which was not responsive to conservative treatment. PTED was performed using dexmedetomidine as sedative and lidocaine as local anesthesia. Measurements included the numeric rating scale (NRS, from 0 to 10) for leg pain, back pain, COMI-back, and NRS for anxiety of anesthesia and perioperative continuously monitored hemodynamics. Furthermore, satisfaction with the sedation was scored by patients, surgeons, and anesthesiologists.

RESULTS

Ninety-two consecutive patients were enrolled. Of all patients, 18.5% had anxiety for undergoing surgery under local anesthesia. All but one patient underwent PTED successfully. There was one case of conversion due to severe, uncontrollable back pain during surgery. Throughout the procedure, hemodynamic parameters showed no clinically relevant change compared to baseline. Anesthesiologic complications were three cases (3.4%) of self-limiting hypoxia and five cases (8.6%) of nausea and/or vomiting. Surgeons and anesthesiologists had a high satisfaction rate (> 87%) with the conscious sedation during the procedure, while satisfaction with sedation was scored 8.4 ± 2.2 by patients.

CONCLUSIONS

PTED performed under local anesthesia and conscious sedation is safe and effective to treat sciatica and yields high satisfaction rates from surgeons, anesthesiologists, and patients.

Lumbar degenerative disease treated by percutaneous endoscopic transforaminal lumbar interbody fusion or minimally invasive surgery-transforaminal lumbar interbody fusion: a case-matched comparative study

Purpose

This study aimed to evaluate the clinical efficacy and imaging results of percutaneous endoscopic transforaminal lumbar interbody fusion (PETLIF) through comparing it with minimally invasive surgery-transforaminal lumbar interbody fusion (MISTLIF).

Materials and methods

We performed a retrospective analysis on patients with lumbar degenerative disease treated by PETLIF or MISTLIF from September 2017 to January 2019, and the patients were divided into two groups: the PETLIF group and the MISTLIF group. The clinical and imaging parameters of the two groups were evaluated.

Results

There was no significant difference between the two groups in complication rate. The operative time in the PETLIF group was significantly less than that in the MISTLIF group. Compared with those before operation, the postoperative VAS-L and VAS-B scores were significantly improved after operation in the both groups. In addition, the postoperative VAS-B score of the PETLIF group was significantly lower than that of the MISTLIF group. At the last follow-up, there was no significant difference between the two groups in the VAS-L score, VAS-B score, ODI score, and bony fusion rate.

Conclusions

Both PETLIF and MISTLIF could achieve satisfactory clinical outcomes in the treatment of lumbar degenerative disease, but our study suggested that PETLIF had less damage, rapid recovery after operation, and short discharge time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02841-4.

Transforaminal Endoscopic Decompression of Facet Cysts by Interventional Pain Physicians

Lumbar synovial cysts (LSC) can impinge neural structures, causing radicular back pain. Conservative treatment options; however, are often ineffective, and traditional surgical techniques can cause joint instability. We describe two cases in which interventional pain physicians used transforaminal endoscopic spine surgery to treat LSC. The patients reported complete resolution of their lower back and radicular pain and the procedures preserved their motor function and sensation in their bilateral lower extremities. This technique is a viable option for remediation of LSC and can be performed by well-trained pain physicians.

A novel vertebral trench technique (VTT) involving transforaminal endoscopic lumbar foraminotomy (TELF) for very highly up-migrated lumbar disc herniation above L5

BACKGROUND

Percutaneous endoscopic lumbar discectomy (PELD) has become popular for the treatment of symptomatic lumbar disc herniation (LDH). The very highly up-migrated lumbar disc herniation (VHUM-LDH) is difficult to remove under PELD. The purpose of this research is to investigate the feasibility, clinical efficacy and operative nuances of a novel VTT involving TELF for this type of herniation.

METHODS

Eleven patients with very highly up-migrated LDH who underwent VTT involving TELF discectomy from May 2016 to May 2019 were included in this study. The operative time, length of hospital stay, and postoperative complications were recorded. Pre-and postoperative radiologic findings were investigated. All the patients were followed more than 1 year. The visual analogue score (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores and modified MacNab criteria were used to assess surgical efficacy.

RESULTS

All the 11 patients underwent successful surgery. We compared the VAS, ODI, and JOA scores before and after surgery. The differences were statistically significant (P < 0.05). According to the modified MacNab criteria, 10 patients were assessed as "excellent", 1 patient was assessed as "good" at the last follow up.

CONCLUSION

The novel VTT involving TELF discectomy is a supplement to the traditional PELD. This technique enables the endoscope with working cannula to get closer the sequestrated nucleus pulposus without irritating the exiting nerve root, and facilitates the nucleus pulposus be removed successfully under direct visualization. The VTT involving TELF discectomy can be a safe, effective and feasible surgical procedure for the treatment of LDH with very highly up-migrated.

Variation in spatial distance between the lumbar interlaminar window and intervertebral disc space during flexion-extension

PURPOSE

Knowledge of interlaminar space is important for undertaking percutaneous endoscopic discectomy via an interlaminar approach (PED-IL). However, dynamic changes in the lumbar interlaminar space and the spatial relationship between the interlaminar space and intervertebral disc space (IDS) are not clear. The aim of this study was to anatomically clarify the changes in interlaminar space height (ILH) and variation in distance between the two spaces during flexion-extension of the lumbar spine in vitro.

METHODS

First, we used a validated custom-made loading equipment to obtain neutral, flexion, and extension 3D models of eight lumbar specimens through 3D reconstruction software. Changes in ILH (ILH, IL-yH, IL-zH) and distances between the horizontal plane passing through the lowest edge of the lamina of the superior lumbar vertebrae and the horizontal plane passing through the lowest position of the trailing edge of the same-level IDS (DpLID) at L3/4, L4/5 and L5/S1 were examined on 3D lumbar models.

RESULTS

We found that ILH was greater at L4/5 than at L3/4 and L5/S1 in the neutral position, but the difference was not significant. In the flexion position, ILH was significantly more than that in neutral and extension positions at L3/4, L4/5, and L5/S1. There were significantly more DpLID changes from neutral to flexion than that from neutral to extension at all levels (L3/4, L4/5, L5/S1).

CONCLUSION

These findings demonstrated level-specific changes in ILH and DpLID during flexion-extension. The data may provide a better understanding of the spatial relationship between lumbar interlaminar space and IDS, and aid the development of segment-specific treatment for PED-IL.

Percutaneous Full-Endoscopic C2 Ganglionectomy for the Treatment of Intractable Occipital Neuralgia: Technical Note

BACKGROUND

The C-2 dorsal root ganglionectomy procedure can provide effective treatment for intractable occipital neuralgia (ON). However, the traditional microsurgery of C2 ganglionectomy needs a wide incision and significant paraspinous muscle dissection for adequate visualization. The indications of endoscopic spine surgery are ever expanding, with the development of endoscopic armamentaria and technological innovations.

OBJECTIVE

To validate the feasibility of the approach and describe several operative nuances based on the authors' experience. In this paper, the authors describe a patient with intractable ON who was successfully treated with a percutaneous full-endoscopic C2 ganglionectomy.

METHODS

We describe the case of an 83-yr-old female with a 2-yr history of left ON who did not respond to a series of treatments, including physical therapy, drug therapy, injection therapy, and radiofrequency therapy. After careful examination, we performed a percutaneous, full-endoscopic left C2 ganglionectomy.

RESULTS

The patient was successfully treated with a percutaneous full-endoscopic ganglionectomy. Afterwards, her intractable and constant pain was relieved. There was no cerebrospinal fluid leakage, incision infection, neck deformity, or other complications.

CONCLUSION

C2 ganglionectomy can be accomplished successfully using a full-endoscopic uniportal surgical technique under continuous irrigation, which has the advantages of excellent illumination and visualization, reduced surgery-related trauma, and reduced bleeding.

Anatomical Importance Between Neural Structure and Bony Landmark: Clinical Importance for Posterior Endoscopic Cervical Foraminotomy

Objective

Posterior endoscopic cervical foraminotomy (PECF) is a well-established, minimally invasive surgery for cervical radiculopathy, but have the more chances of neural structure damage due to the limited visibility and steeper learning curve. So, the anatomical understanding of the nerve associated with the bony structure will be an essential surgical guideline.

Methods

We measured the distance between the bilateral dura lateral edge and bilateral V-point on axial cuts of cervical magnetic resonance imaging and 3-dimensional spine computed tomography imaging, respectively, from 80 patients. We then calculate the distance and position between the dura lateral edge and the V-point as surgically critical width (SCW). Transverse interdural distance (TIDW), transverse inter-V-point distance, and anatomical facet joint width were measured.

Results

The mean TIDW decreased as the levels down in the 40s–60s but increased at the C4–5, C5–6, and C6–7 levels in the 70s. Statistically significant difference was shown at the C6–7 level between the 40s and the 70s. The mean anatomical inter-V-point distance markedly decreased at C5–6 and continued till the C7–Tl level at all age groups. Moreover, a statistically significant difference was shown at the C3–4 and C4–5 level between the 40s and the 70s. The mean negative values of SCW increased from the 40s to 70s at the C5–6 and C6–7 levels (C5–6: -0.60 ± 1.10 mm to -1.63 ± 1.56 mm; C6–7: -0.90 ± 0.74 mm to -2.18 ± 1.25 mm). There were statistically significant differences between the 2 aged groups at the C3–4, C4–5, C5–6, and C6–7 levels.

Conclusion

A prediction of the correlated position between the lateral dura edge and the V-point is essential for the PECF not to injure the neural structure. In the case of a performing the PECF at the C5–6 and C6–7 level in the old-aged patient, it should be considered the laterally moved dura edge, and more extended bony remove is needed for less neural structure damage.

Fluid Lubrication and Cooling Effects in Diamond Grinding of Human Iliac Bone

Background and Objectives: Although there have been research on bone cutting, there have been few research on bone grinding. This study reports the measurement results of the experimental system that simulated partial laminectomy in microscopic spine surgery. The purpose of this study was to examine the fluid lubrication and cooling in bone grinding, histological characteristics of workpieces, and differences in grinding between manual and milling machines. Materials and Methods: Thiel-fixed human iliac bones were used as workpieces. A neurosurgical microdrill was used as a drill system. The workpieces were fixed to a 4-component piezo-electric dynamometer and fixtures, which was used to measure the triaxial power during bone grinding. Grinding tasks were performed by manual activity and a small milling machine with or without water. Results: In bone grinding with 4-mm diameter diamond burs and water, reduction in the number of sudden increases in grinding resistance and cooling effect of over 100 °C were confirmed. Conclusion: Manual grinding may enable the control of the grinding speed and cutting depth while giving top priority to uniform torque on the work piece applied by tools. Observing the drill tip using a triaxial dynamometer in the quantification of surgery may provide useful data for the development of safety mechanisms to prevent a sudden deviation of the drill tip.

Effect of Durotomy versus Myelotomy on Tissue Sparing and Functional Outcome after Spinal Cord Injury

Various surgical strategies have been developed to alleviate elevated intraspinal pressure (ISP) following acute traumatic spinal cord injury (tSCI). Surgical decompression of either the dural (durotomy) or the dural and pial (myelotomy) lining of the spinal cord has been proposed. However, a direct comparison of these two strategies is lacking. Here, we compare the histological and functional effects of durotomy alone and durotomy plus myelotomy in a rodent model of acute thoracic tSCI. Our results indicate that tSCI causes local tissue edema and significantly elevates ISP (7.4 ± 0.3 mmHg) compared with physiological ISP (1.7 ± 0.4 mmHg; p < 0.001). Both durotomy alone and durotomy plus myelotomy effectively mitigate elevated local ISP (p < 0.001). Histological examination at 10 weeks after tSCI revealed that durotomy plus myelotomy promoted spinal tissue sparing by 13.7% compared with durotomy alone, and by 25.9% compared with tSCI-only (p < 0.0001). Both types of decompression surgeries elicited a significant beneficial impact on gray matter sparing (p < 0.01). Impressively, durotomy plus myelotomy surgery increased preservation of motor neurons by 174.3% compared with tSCI-only (p < 0.05). Durotomy plus myelotomy surgery also significantly promoted recovery of hindlimb locomotor function in an open-field test (p < 0.001). Interestingly, only durotomy alone resulted in favorable recovery of bladder and Ladder Walk performance. Combined, our data suggest that durotomy plus myelotomy following acute tSCI facilitates tissue sparing and recovery of locomotor function. In the future, biomarkers identifying spinal cord injuries that can benefit from either durotomy alone or durotomy plus myelotomy need to be developed.

Thoracic Endoscopic Spine Surgery: A Comprehensive Review

BACKGROUND

From the 1990s, there has been growth in the literature demonstrating the feasibility of minimally invasive approaches for treating diverse spinal disorders. There is still much work to be done in circumnavigating the technical challenges and elucidating relative advantages of endoscopic techniques in spine surgery. In this comprehensive literature review, we discuss the history, advantages, disadvantages, approaches, and technology of, and critically examine peer-reviewed studies specifically addressing, endoscopic thoracic spinal surgery.

METHODS

Literature review was conducted with the key words "endoscopic," "minimally invasive," and "thoracic spinal surgery," using PubMed, Web of Science, and Google Scholar.

RESULTS

Review of 241 thorascopic procedures showed a success rate of 98% to 100%, low morbidity, and favorable complication profile. Review of 115 thoracic fixation procedures demonstrated high success rate, and 87% of screw positions were rated "good." Review of 55 full endoscopic uniportal decompressions showed sufficient decompression in most patients. Match pair analysis of 34 patients comparing video-assisted thoracoscopy surgery (VATS) or posterior spinal fusion reported the VATS group had increased operative duration but reduced blood loss.

CONCLUSIONS

Based on our literature review, there is a high rate of positive outcomes with endoscopic thoracic spine surgery, which reduces tissue dissection, intraoperative blood loss, and epidural fibrosis. However, the technical challenge highlights the importance of further training and innovation in this rapidly evolving field.

LEVEL OF EVIDENCE

3.

CLINICAL RELEVANCE

There is growing evidence demonstrating the success of endoscopic thoracic spinal surgery. Populations that could be helped include the elderly and immunocompromised, who would benefit from decreased hospital stay and enhanced recovery time.

Posterior Endoscopic Cervical Decompression: Review and Technical Note

Endoscopic spine surgery for the treatment of degenerative spinal diseases from lumbar to cervical spine has accelerated over the past 2 decades. Posterior endoscopic cervical discectomy (PECD) has been described as a safe, effective, and minimally invasive procedure for cervical radiculopathy or even part of the myelopathy. This procedure also has been validated with comparable outcomes to open and microscopic surgery. Radiculopathy due to foraminal disc herniation or foraminal stenosis should be the optimum indications of this procedure. Intraoperative 3-dimensional navigation can help surgeons to get quick and great quality guidance for endoscopic surgeons. In this review, we will focus on the technical details and evidence-based results of PECD which is a promising procedure for cervical radiculopathy with the advantages of a minimally invasive method.

Full endoscopic unilateral laminotomy for bilateral decompression of the cervical spine: surgical technique and early experience

Background

Full-endoscopic decompression surgery has been shown to be safe and efficacious in the lumbar spine, while its role remains to be determined in the cervical spine. We describe the utility of cervical endoscopic unilateral laminotomy for bilateral decompression (CE-ULBD) in a series of elderly patients with severe central stenosis, significant medical comorbidity, and existing cervical deformity.

Methods

A prospectively collected spine surgery registry at the University of Washington was retrospectively queried for patients with cervical spondylotic myelopathy receiving CE-ULBD. Demographic data, operative details, imaging, and patient reported outcomes, including visual analogue scale (VAS) for neck and upper extremity pain, Nurick grade, and the modified Japanese Orthopedic Association (mJOA) score, were reviewed. Description of the surgical technique is provided. Descriptive statistics were calculated.

Results

From 2014 through 2018, 10 patients with an average age of 70.2±5.0 years underwent CE-ULBD for symptomatic upper cervical stenosis due to ligamentum flavum buckling. Half of these patients had one stenotic segment, the other half had two stenotic segments. The most commonly affected segment was C3/4 (5/10 patients). Average length of surgery was 128±18.4 minutes. Average length of stay was 1.2±0.2 days. Average clinical follow-up time was 22.0±4.7 months; clinical outcomes at most recent follow-up were improved via both the Nurick grade (1.2±0.4, P<0.01) and modified Japanese Orthopedic Association (14.6±1.0, P<0.001) compared with pre-operative values. One patient experienced a transient loss of motor evoked potentials intraoperatively, but there were no cases of permanent neurological deficit.

Conclusions

Severe central cervical stenosis is a safe and viable target for full-endoscopic decompression via an interlaminar approach.