Evolution of Spinal Endoscopic Surgery

Comparative study of the learning curves for percutaneous endoscopic interlaminar lumbar discectomy and unilateral biportal endoscopy techniques

BACKGROUND

Minimally invasive spinal surgery techniques, such as Percutaneous Endoscopic Interlaminar Lumbar Discectomy (PEID) and Unilateral Biportal Endoscopy (UBE), have been developed to reduce surgical morbidity and enhance patient recovery. Although both techniques demonstrate promising clinical outcomes, the learning curves required for surgeons to achieve proficiency with these methods remain unclear.

OBJECTIVE

To compare the learning curves of PEID and UBE in the treatment of lumbar disc herniation.

METHODS

We conducted a retrospective analysis of 173 patients who underwent either PEID (n = 94) or UBE (n = 79), performed by two independent surgeons between January 2020 and January 2022. Eligible patients were aged 18-75 years, diagnosed with lumbar disc herniation, and had no previous spinal surgeries at the affected level. Metrics analyzed included operative time, intraoperative blood loss, postoperative recovery, complication rates, and clinical outcomes, assessed using the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores.

RESULTS

The PEID group demonstrated significantly shorter operative times (99.96 ± 34.74 min vs. 116.52 ± 47.20 min, P < 0.05) and less blood loss (20.85 ± 11.06 ml vs. 80.19 ± 22.81 ml, P < 0.01) compared to the UBE group. Both techniques showed significant improvements in VAS and ODI scores postoperatively, with no significant differences between the groups at any follow-up points. Learning curve analysis revealed that operative times for PEID stabilized at approximately 70 min after about 40 cases, while UBE stabilized at around 65 min after approximately 35 cases. Complication rates were low, and patient satisfaction was high in both groups. According to the Modified MacNab criteria, 83% of patients in the PEID group and 79.7% in the UBE group achieved excellent outcomes, while only 5.3% and 3.8% of patients experienced fair or poor outcomes in the PEID and UBE groups, respectively.

CONCLUSION

Both PEID and UBE are effective minimally invasive techniques for the treatment of lumbar disc herniation, offering comparable clinical outcomes and low complication rates. However, PEID is associated with shorter operative times and reduced intraoperative blood loss. Understanding the learning curves of these techniques is crucial for surgeons to improve proficiency and optimize patient outcomes.

Comparing the efficacy and safety of biportal endoscopic discectomy with microscopic discectomy for lumbar herniated intervertebral disc: a multicentre, prospective, assessor-blinded, randomized controlled trial

Aims

The aim of this study was to compare the efficacy and safety of biportal endoscopic discectomy (BED) with microdiscectomy (MD) in patients with a single-level lumbar disc herniation, and to determine whether BED gives similar clinical outcomes to MD but with potential additional benefits.

Methods

Included in this multicentre, prospective, assessor-blind, randomized controlled trial were patients with a single-level lumbar disc herniation requiring surgical intervention. These were recruited from six hospitals between 13 July 2021 and 16 September 2022, and followed up for 12 months. The interventions were either BED (n = 50) or MD (n = 50). The primary outcome was the Oswestry Disability Index (ODI) at 12 months postoperatively.

Results

In total, 100 patients were randomized into the BED and MD groups based on computer-generated allocation. The analysis included 41 and 46 patients from the MD and BED groups, respectively. At 12 months, the mean ODI scores were comparable between the BED (10.92; SD 12.93) and MD (10.32; SD 12.55) groups (mean difference 0.61 (95% CI -4.47 to 5.68); p = 0.816). No serious adverse event was seen in either group. Compared to the MD group, the BED group showed slightly lower surgical site pain at 24 (p = 0.004) and 48 hours postoperatively (p = 0.014), lower serum creatine phosphokinase (CPK) (p = 0.003), better scar quality at three (p = 0.002) and six months (p = 0.007), and a significantly lower rate of wound dehiscence (p = 0.018).

Conclusion

BED is as effective as MD in treating single-level lumbar disc herniation but has distinct advantages in terms of postoperative wound complications. Additionally, BED may offer potential benefits in terms of early postoperative surgical site pain, scar aesthetics, and muscle preservation as indicated by CPK levels. These findings suggest that BED is a safe and effective alternative to MD, offering the benefits of minimal invasiveness while maintaining clinical efficacy.

Surgical treatment of dorsal atlantoaxial pseudoarticulation with full endoscopic approach: illustrative case

BACKGROUND

Atlantoaxial pseudoarticulation is a rare condition characterized by atypical joint formation at C1-2, potentially causing severe neck pain and progressive cervical myelopathy due to spinal cord compression. Traditional treatments often involve decompression with or without fusion and can lead to significant tissue disruption and extended recovery time. Here, the authors describe a novel, minimally invasive full endoscopic technique for resecting atlantoaxial pseudoarticulation, achieving successful spinal decompression.

OBSERVATIONS

A 44-year-old female patient presented with 6 months of progressive cervical myelopathy, including gait instability, right-sided weakness, and numbness. Imaging confirmed a C1-2 pseudoarticulation causing severe spinal cord compression. A paraspinal endoscopic approach was used, avoiding the need for instrumented fusion. Postoperatively, the patient's condition rapidly improved, with complete symptom resolution at 6 months and only mild intermittent hand numbness at 18 months. Imaging confirmed stable, effective decompression without complications.

LESSONS

This case represents the first documented application of a full endoscopic approach for atlantoaxial pseudoarticulation, achieving effective decompression while preserving spinal integrity and reducing recovery time. This technique offers a promising, minimally invasive alternative for complex cervical pathologies, supporting a shift toward less invasive, tissue-sparing spinal surgery. https://thejns.org/doi/10.3171/CASE24766.

Biportal Endoscopic Decompression with Maximized Facet Joint Preservation for Central to Extraforaminal Lumbar Stenosis

Background/Objectives: This is a retrospective study. We aimed to identify an optimal biportal endoscopic spine surgery (BESS) technique that maximizes facet joint preservation while achieving sufficient decompression for central to extraforaminal lumbar stenosis across all spinal levels. Methods: We retrospectively analyzed the data of 46 patients who underwent surgery and assessed clinical outcomes (visual analogue scale scores for pain; pregabalin usage) and radiological changes (using computed tomography/magnetic resonance imaging) in the spinal canal; intervertebral foramen area expansion; facet joint preservation; and degenerative change. Results: Using interlaminar and transforaminal approaches (two-way BESS decompression technique), the mean facet joint volume preservation ratio was 87%, and the mean facet joint length maintenance ratio was 90%, indicating a successful anatomical preservation compared with previous studies. Radiological outcomes revealed effective decompression (178% in the spinal canal; 245% in intervertebral foramen expansion). Additionally, all clinical outcome parameters significantly improved (p < 0.001). Conclusions: To the best of our knowledge, this study is the first to accurately estimate the degree of facet joint preservation using different methods after endoscopic surgery. The two-way BESS decompression technique maximized facet joint preservation with sufficient decompression and clinically improved central to extraforaminal stenosis across all lumbar levels. Therefore, this technique can sufficiently preserve facet joints to prevent rapid degenerative change after surgery.

Electromagnetic Navigation in Biportal Endoscopic Lumbar Spine Surgery

Introduction

Endoscopic Spine Surgery (ESS) has begun to gain traction as an alternative to traditional microscopic spine surgery, particularly for lumbar decompression. However, one of the challenges associated with this approach is the steep learning curve. A recent advancement in this field aims to flatten the learning curve by incorporating navigation into ESS. This technology provides valuable information on the extent of decompression, confirms the working level, and reduces radiation exposure.

Technical Note

We aimed to describe our experience using electromagnetic navigation in biportal endoscopic spine surgery (BESS). The surgical technique is initiated by positioning the patient prone on a radiolucent table. The navigation field generator is positioned over the caudal end of the patient. The navigation system is set up with patient mappers at the desired working levels. The patient tracker is implanted. The final fluoroscopy images are captured in anteroposterior and lateral views. Subsequently, standard incisions are made, and endoscopic decompression is performed. When required, various instruments can be used to confirm the level, angulation, and extent of decompression.

Conclusions

Our experience showed that this approach reduced the need for intraoperative imaging and provided an accurate alternative to repeated intraoperative imaging. However, it does involve a significantly long setup. Further trials of larger scale are required to determine its efficacy.

Learning curve for full-endoscopic lumbar decompression via interlaminar approach using the learning curve cumulative summation analysis

BACKGROUND

Full-endoscopic spine surgery (FESS) is generally considered to have a steep learning curve due to its technical complexity. This study aimed to evaluate the learning curve for full-endoscopic decompressive laminectomy via the interlaminar approach using learning curve cumulative summation test (LC-CUSUM) analysis, which provides objective statistical monitoring of surgical competency acquisition, and determine the number of cases required for surgical competency.

METHODS

We retrospectively analyzed the first 60 consecutive patients who underwent single-level interlaminar endoscopic unilateral lumbar decompression for lumbar spinal stenosis performed by a single surgeon with 4 years of experience. LC-CUSUM analysis was employed with operative time as the primary outcome measure. The target time was set at 80 min, based on the same surgeon's mean operative time for microscopic laminectomy. The patients were divided into the early (≤ 30 cases) and late (> 30 cases) learning periods and compared.

RESULTS

LC-CUSUM analysis revealed that competency was achieved after 51 cases. The mean operative time significantly decreased from 90.20 ± 24.44 min in the early period to 71.47 ± 16.65 min in the late period (p = 0.001). Estimated blood loss showed significant reduction (54.83 ± 42.58 ml vs. 34.83 ± 19.10 ml, p = 0.024). Complication rates remained consistent between periods (10% each), with similar rates of dural tears (6.67% in both periods).

CONCLUSIONS

The results of this study have demonstrated that a learning period of 51 cases could be required to achieve proficiency in full-endoscopic interlaminar lumbar decompression. However, the procedure can be safely performed even during the early learning period by surgeons with adequate microscopic surgical experience.

Revolutionizing the treatment of intervertebral disc degeneration: an approach based on molecular typing

BACKGROUND

Intervertebral disc degeneration (IVDD) is a significant cause of global disability, reducing labor productivity, increasing the burden on public health, and affecting socio-economic well-being. Currently, there is a lack of recognized clinical approaches for molecular classification and precision therapy.

METHODS

Chondrocyte differentiation and prognosis-related genes were extracted from single-cell RNA sequencing and multi-omics data in the Gene Expression Omnibus (GEO) database through chondrocyte trajectory analysis and non-parametric tests. Subsequently, a precise IVDD risk stratification system was developed using ConsensusClusterPlus analysis. The clinical significance of molecular typing was demonstrated through case-control trials involving IVDD patients. Specific inhibitors of molecular typing were predicted using the pRRophetic package in R language and then validated in vitro.

RESULTS

A stratified model for IVDD, considering chondrocyte differentiation and demonstrating high clinical relevance, was developed using a set of 44 chondrocyte fate genes. Extensive analyses of multi-omics data confirmed the clinical relevance of this model, indicating that cases in the High Chondrocyte Scoring Classification (HCSC) group had the most favorable prognosis, whereas those in the Low Chondrocyte Scoring Classification (LCSC) group had the worst prognosis. Additionally, clinical case-control studies provided evidence of the utility of IVDD molecular typing in translational medicine. A gene expression-based molecular typing approach was used to create a matrix identifying potential inhibitors specific to each IVDD subtype. In vitro experiments revealed that gefitinib, a drug designed for LCSC, not only had protective effects on chondrocytes but also could induce the conversion of LCSC into the HCSC subgroup. Therefore, IVDD molecular typing played a critical role in assisting clinicians with risk stratification and enabling personalized treatment decisions.

CONCLUSION

The results of the study have provided a comprehensive and clinically relevant molecular typing for IVDD, involving a precise stratification system that offers a new opportunity for customizing personalized treatments for IVDD.

A Critical Review of Endoscopic Spine Surgery

This is a critical review of the data supporting current endoscopic surgical techniques for the spine, limitations, economic barriers to adoption, and the future of the field. Endoscopic spine approaches can be applied to all levels of the spine, with many robust trials supporting its clinical outcomes. Although financial limitations with starting an endoscopic program can be justified by its cost effectiveness and positive societal impact, challenges facing its widespread adoption are present and more endoscopic spine programs are needed. Technological advancements will further enhance endoscopic techniques as they become an integral part of a spine surgeon's repertoire.

Posterior and Transforaminal Lumbar Interbody Fusion: Recent Advances in Technique and Technology

Posterior approach interbody fusion techniques such as posterior lumbar interbody fusion and transforaminal interbody fusion are known as the workhorse procedures for lumbar spinal fusion. Over the years, advancements in procedural steps, technique, and technology have sought to improve patient outcomes. Within the last 2 decades, considerable emphasis has been placed upon minimally invasive techniques utilizing tubular retractors and conscious sedation. Innovation in materials engineering, visualization technology such as endoscopes, and enabling technologies such as augmented reality and robotics have served to enhance the procedures and their outcomes.

Less Is More: Evaluating the Benefits of Minimally Invasive Spinal Surgery

This review aims to explore the evolution, techniques, and outcomes of minimally invasive spine surgery (MISS) within the field of neurosurgery. We sought to address the increasing burden of spine degeneration in a rapidly aging population and the need for optimizing surgical management. This review explores various techniques in MISS, drawing upon evidence from retrospective studies, case series, systematic reviews, and technological advancements in neurosurgical spine treatment. Various approaches, including endonasal cervical, transoral cervical, transcervical, mini-open/percutaneous, tubular, and endoscopic techniques, provide alternatives for current approaches to a range of spinal pathologies. The main findings of this review highlight potential advantages of MISS over traditional open surgery, including reduced complications, shorter hospital stays, and improved patient outcomes. Our research underscores the importance of adopting MISS techniques to optimize patient care in neurosurgical spine treatment.

Comparative Outcomes of Biportal Endoscopic Decompression, Conventional Subtotal Laminectomy, and Minimally Invasive Transforaminal Lumbar Interbody Fusion for Lumbar Central Stenosis

OBJECTIVE

Spinal stenosis is a prevalent condition; however, the optimal surgical treatment for central lumbar stenosis remains controversial. This study compared the clinical outcomes and radiological parameters of 3 surgical.

METHODS

unilateral laminectomy bilateral decompression with unilateral biportal endoscopy (ULBD-UBE), conventional subtotal laminectomy (STL), and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

METHODS

This retrospective study included 86 patients, divided into ULBD-UBE (n=34), STL (n=24), and MIS-TLIF (n=28) groups. We evaluated demographics and perioperative factors and assessed clinical outcomes using the visual analogue scale (VAS), Oswestry Disability Index (ODI), and neurogenic intermittent claudication (NIC). Radiological parameters assessed included lumbar lordosis, L4S1 Cobb angle (L4S1), T12S1 Cobb angle (T12S1), increased cross-sectional dural area (CSA), dynamic angulation (DA), dynamic slip (DS), and development of postoperative instability.

RESULTS

The ULBD-UBE group showed a significantly shorter hospital stay duration and operation time and reduced blood loss than the other groups (p<0.001). ULBD-UBE group showed a trend towards greater VAS and ODI improvement at 1 month and postoperative NIC symptom relief. Radiologically, MIS-TLIF group exhibited lower postoperative DA and DS (p<0.001), indicating higher postoperative stability. Postoperative instability was lower in the ULBD-UBE group (2.9%) than in the STL group (16.7%) and similar to the MIS-TLIF group (0.0%) (p=0.028). The CSA was highest in the MIS-TLIF group (295.5%) compared to that in the other groups (ULBD-UBE, 216.3%; STL, 245.2%) (p<0.001).

CONCLUSION

Compared to other procedures, ULBD-UBE is a safe, effective, and viable surgical procedure for treating lumbar central stenosis.

Dimensions of bony Kambin's triangle pertaining to endoscopic procedure

Background

Endoscopic procedures nowadays are successful, minimally invasive, and safer, with fewer intraoperative and postoperative complications and shorter hospital stays. Kambin's triangle (KT) is the three-dimensional configuration that is used as a transforaminal anatomical corridor for epidural steroid injections and endoscopic surgeries for various lumbar pathologies. This study aims to estimate the dimensions of KT and diameter of the cannula for the transforaminal surgical approaches using KT in the Chhattisgarh population.

Methods

Seven human cadavers (three males and four females) were included in the study for observing KT. Dissection was done to carefully clear landmarks, including the vertebral bodies, intervertebral disc, exiting nerve root, and superior articular process. Base (a horizontal plane passing through the superior border of the caudal vertebra) and height (along the superior articular process of the inferior vertebra in line with the articular facet) were measured. Hypotenuse, semiperimeter of the triangle, area of triangle, diameter, and area of the inscribed circle were calculated.

Results

Height, base, and inscribed circle diameter increased from L1-L2 to L4-L5 then decreased to L5-S1. There was no statistically significant difference between males and females. The safest admissible cannula diameter according to the current study that can be used at all levels in KT was 6.06 mm.

Conclusion

This study provides the safest cannula size to be considered in the patients of the Chhattisgarh population during transforaminal approaches in the lumbar area. Minimally invasive surgery and shorter hospitalization are vital criteria to evaluate any surgery these days.

Lumbar Endoscopic Unilateral Laminectomy for Bilateral Decompression in Degenerative Spondylolisthesis

BACKGROUND

Degenerative spondylolisthesis is an important cause of chronic low back pain and radiculopathy in the adult U.S.

POPULATION

Open decompression with or without fusion is considered the standard for management, yet optimal treatment remains controversial. Full endoscopic spine surgery offers an alternative surgical approach with possible advantages. There is a paucity of data on the use of full endoscopic spinal surgery in degenerative spondylolisthesis. Therefore, we present the clinical and radiographic outcomes of 73 patients with low-grade degenerative spondylolisthesis with severe stenosis, who underwent lumbar endoscopic unilateral laminectomy for bilateral decompression.

METHODS

Patients with low-grade degenerative spondylolisthesis who underwent a lumbar endoscopic ULBD at 6 spine centers in North America were included in this study. Patients were followed up at 3, 9, and 12 months. Static and dynamic imaging was performed and evaluated routinely before surgery to identify the pathology and grade of spondylolisthesis. Patient-reported outcomes were prospectively collected.

RESULTS

This study included 73 patients from 6 spine centers. Sixty-two patients were diagnosed with grade I spondylolisthesis, whereas 11 were diagnosed with grade II spondylolisthesis. Postoperatively, 70 patients reported improved symptoms and pain resolution, whereas 3 patients reported worse pain. Mean visual analog scale back and visual analog scale leg scores and Oswestry Disability Index showed a statistically significant improvement at 3, 9, and 12 months compared with the preoperative period. Radiographically, no patient in our study had progression of the grade of spondylolisthesis.

CONCLUSIONS

Patients with low-grade degenerative spondylolisthesis causing severe stenosis can safely be treated with lumbar endoscopic unilateral laminectomy for bilateral decompression. A head-to-head trial should be undertaken to provide a higher level of clinical evidence.

Clinical outcomes of fenestration discectomy and iLESSYS-Delta interlaminar endoscopic system for treatment of LDH: a single-center retrospective cohort study

To compare the clinical efficacy of interlaminar endoscopic surgical system delta (iLESSYS-Delta) discectomy with that of classical fenestration discectomy for treating lumbar disc herniation. Patients who underwent iLESSYS-Delta or fenestration discectomy were enrolled in this study. Baseline information and clinical indicators were collected. The baseline data were matched using propensity score matching. Fifty-two patients were in each group. In the iLESSYS-Delta cohort, the volume of intraoperative bleeding was 18.17 ± 4.20 ml, the length of postoperative hospital stay was 4.16 ± 2.29 days, and the length of postoperative off-bed activity was 1.58 ± 0.88 days. In contrast, in the fenestration group, the volume of intraoperative bleeding was 32.50 ± 17.13 ml, the length of postoperative hospital stay was 6.66 ± 2.44 days, and the length of postoperative off-bed activity was 3.18 ± 1.28 days. The difference between the two groups was statistically significant (P < 0.05). The operation time was 88.90 ± 19.14 min in the iLESSYS-Delta group and 67.63 ± 19.32 min in the fenestration group, and the difference between the two groups was statistically significant (P < 0.05). Regarding the pain visual analogue scale scores at 24, 48, and 72 h after surgery, patients in the iLESSYS-Delta group had less pain than did those in the fenestration group (P < 0.05). The Oswestry disability indices of postoperative patients in both groups significantly improved at 3 months after surgery and at the last follow-up (P < 0.05); however, there was no statistically significant difference in the postoperative ODI scores between the two surgery groups (P > 0.05). The two groups showed no significant differences in clinical effects, postoperative recurrence rates, or perioperative complications. iLESSYS-Delta can cause less intraoperative bleeding and faster recovery than fenestration discectomy.

Enhancing Cadaver Labs for Endoscopic Spine Surgery: The Glove as the "Lesion"

OBJECTIVE

We describe a novel yet simple training exercise for residents who are being introduced to endoscopic spine surgery.

METHODS

Prior to residents training on the endoscopic interlaminar approach, the course faculty performed an endoscopic transforaminal approach and inserted a small piece of a surgical glove into the ventral epidural space of a cadaveric torso. The transforaminal approach did not alter the anatomy of the interlaminar approach, so the residents were able to practice as if it were a de novo situation. Placing the small "lesion" provided an exercise to confirm the residents were able to safely access the area and provided practice for them to carefully grasp the "lesion" and remove it. Prior to resident training on the endoscopic transforaminal approach, the course faculty utilized an interlaminar approach to place the "lesion." A questionnaire with a five-point Likert scale of agreement was completed by the residents to assess their experience with the training exercise.

RESULTS

Five residents attended the cadaver lab, and 100% strongly agreed that the cadaver lab provided a realistic representation of the procedure demonstrated, the "lesion" removal added to their educational experience, and they were overall satisfied with the educational session.

CONCLUSIONS

One of the lessons learned with this exercise that we will consider in future courses would be to place a radiodense "lesion" that could be visualized on fluoroscopy and serve as a radiologic target to find. This can help guide the trainee in knowing where to search if the "lesion" is more difficult to find.

New ipsilateral full endoscopic interlaminar approach for L5-S1 foraminal and extraforaminal decompression: technique description and initial case series

BACKGROUND

The L5-S1 interlaminar access described in 2006 by Ruetten et al. represented a paradigm shift and a new perspective on endoscopic spinal approaches. Since then, the spinal community has shown that both the traditional ipsilateral and novel contralateral interlaminar approaches to the L5-S1 foramen are good alternatives to transforaminal access. This study aimed to provide a technical description and brief case series analysis of a new endoscopic foraminal and extraforaminal approach for pathologies at the lumbar L5-S1 level using a new ipsilateral interlaminar approach.

METHODS

Thirty patients with degenerative stenotic conditions at the L5-S1 disc level underwent the modified interlaminar approach. The surgical time, blood loss, occurrence of complications, and clinical outcomes were recorded. The data were compiled in Excel and analyzed using R software version 4.2. All continuous variables are presented as the mean, median, minimum, and maximal ranges. For categorical variables, data are described as counts and percentages.

RESULTS

Thirty patients were included in the study. The cohort showed significant improvements in all quality-of-life scores (ODI, visual analog scale of back pain, and visual analog scale of leg pain). Five cases of postoperative numbness and three cases of postoperative dysesthesia have been reported. No case of durotomy or leg weakness has been reported.

CONCLUSIONS

The fundamental change proposed by this procedure, the new ipsilateral approach, presents potential advantages to surgeons by overcoming anatomical challenges at the L5-S1 level and by providing surgeon-friendly visualization and access. This approach allows for extensive foraminal and extraforaminal decompression, including the removal of hernias and osteophytosis, without causing neural retraction of the L5-S1 roots while maintaining the stability of the operated level.

Three-dimensional endoscopy in lumbar spine surgery as a novel approach for degenerative pathologies: a case report

Endoscopic spine surgery has evolved exponentially. However, the two-dimensional (2D) view results in lack of stereoscopic vision and depth perception, contributing to the steep learning curve. This case report recounts a world first trial of a three-dimensional (3D) endoscopic system that converts 2D to 3D images and explores its potential role in the surgical management of degenerative lumbar spine diseases. The 3D endoscopic system was used for two patient cases and both 2D and 3D images were displayed side by side and compared. Advantages of the 3D endoscopic system include increased perception of depth, rapid identification of bleeding points, and greater visualization of anatomical details. Field of view and exposure were identical in 2D and 3D views. Limitations include costs and need for additional equipment. Overall, 3D endoscopy improved depth perception, instrument manoeuvrability, and recognition of anatomical details. This case report can guide further research and training in endoscopic spine surgery.

The Importance of Planning Ahead: A Three-Dimensional Analysis of the Novel Trans-Facet Corridor for Posterior Lumbar Interbody Fusion Using Segmentation Technology

BACKGROUND

The rise of minimally invasive lumbar fusions and advanced imaging technologies has facilitated the introduction of novel surgical techniques with the trans-facet approach being one of the newest additions. We aimed to quantify any pathology-driven anatomic changes to the trans-facet corridor, which could thereby alter the ideal laterality of approach to the disc space.

METHODS

In this retrospective cohort study, we measured the areas and maximum permissible cannula diameters of the trans-facet corridor using commercially available software (BrainLab, Munich, Germany). Exiting and traversing nerve roots, thecal sacs, and lumbar vertebrae were manually segmented on T2-SPACE magnetic resonance imaging. Spondylolisthesis, disc protrusions, and disc space heights were recorded.

RESULTS

A total of 118 trans-facet corridors were segmented bilaterally in 16 patients (65.6 ± 12.1 years, 43.8% female, body mass index 29.2 ± 5.1 kg/m2). The mean areas at L1-L2, L2-L3, L3-L4, and L4-L5 were 89.4 ± 24.9 mm2, 124 ± 39.4 mm2, 123 ± 26.6 mm2, and 159 ± 42.7 mm2, respectively. The mean permissible cannula diameter at the same levels were 7.85 ± 1.43 mm, 8.98 ± 1.72 mm, 8.93 ± 1.26 mm, and 10.2 ± 1.94 mm, respectively. Both parameters increased caudally. Higher degrees for spondylolisthesis were associated with larger areas and maximum cannula diameters on regression analysis (P < 0.001).

CONCLUSIONS

Our results illustrate that pathology, like spondylolisthesis, can increase the area of the trans-facet corridor. By understanding this effect, surgeons can better decide on the optimal approach to the disc while taking into consideration a patient's unique anatomy.

Efficacy of Biportal Endoscopic Decompression for Lumbar Spinal Stenosis: A Meta-Analysis With Single-Arm Analysis and Comparative Analysis With Microscopic Decompression and Uniportal Endoscopic Decompression

BACKGROUND AND OBJECTIVE

Biportal endoscopic decompression is a minimally invasive surgical technique for lumbar spinal stenosis (LSS). This meta-analysis aimed to evaluate the efficacy and safety of biportal endoscopic decompression through both a single-arm analysis and a comparative analysis.

METHODS

A comprehensive literature search was conducted to identify eligible studies reporting the outcomes of biportal endoscopic decompression for LSS. Single-arm analysis and comparisons with microscopic and uniportal endoscopic decompression were performed. Evaluated outcomes included visual analog scale (VAS) scores for back pain and leg pain, Oswestry Disability Index (ODI) scores, operation time, estimated blood loss, duration of hospital stay, and adverse events.

RESULTS

Single-arm analysis demonstrated significant improvements in VAS back pain, VAS leg pain, and ODI scores after biportal endoscopic decompression at postoperative 1-day to 36-month follow-up (all P < .001), compared with preoperative levels. The pooled mean single-level operation time was 71.44 min, and the pooled mean hospital stay was 3.63 days. The overall adverse event rate was 4.0%, with dural tear being the most common complication (3.0%). Compared with microscopic decompression, biportal endoscopic decompression showed significantly lower VAS back pain at 1-month ( P < .001) and 6-month ( P < .001) follow-up; lower VAS leg pain at 1-month ( P = .045) follow-up; lower ODI scores at 3-month ( P < .001), 12-month ( P = .017), and >12-month ( P = .007) follow-up; lower estimated blood loss ( P = .003); and shorter hospital stay ( P < .001). Adverse event rates did not differ between the techniques. No significant differences were observed between biportal endoscopic and uniportal endoscopic decompression groups for most efficacy and safety outcomes.

CONCLUSION

Biportal endoscopic decompression emerges as a safe and effective alternative for LSS, presenting potential advantages over the microscopic technique and comparable efficacy with the uniportal endoscopic technique.

Is endoscopic technique an effective and safe alternative for lumbar interbody fusion? A systematic review and meta-analysis

Study design

Systematic review; meta-analysis.

Purpose

Lumbar degenerative disease is frequent and has a tremendous impact on patients' disability and quality-of-life. Open and minimally invasive procedures have been used to achieve adequate decompression and fusion. Endoscopic lumbar interbody fusion (Endo-LIF) is emerging as an alternative, trying to reduce morbidity, while achieving comparable to superior clinical outcomes. The aim of this work is to perform a systematic review and meta-analysis to investigate how Endo-LIF compares to open or minimally invasive procedures.

Methods

Electronic databases (MEDLINE, Scopus, Web of Science, Cochrane) were systematically reviewed using the query: '(percutaneous OR endoscop*) AND (open OR minimal* invasive) AND lumbar AND fusion'. PRISMA guidelines were followed.

Results

Twenty-seven articles were included (25 cohort study, 1 quasi-experimental study, and 1 randomized control trial; for meta-analytical results, only observational studies were considered). Endo-LIF conditioned longer operative time, with significantly lower blood loss, bedtime, and hospital length of stay. Early post-operative back pain favored endoscopic techniques. Endo-LIF and non-Endo-LIF minimally invasive surgery displayed comparable results for most back and leg pain or disability outcomes, despite Endo-LIF having been associated with higher disability at late follow-up (versus Open-LIF). No differences were found regarding fusion rates, cage subsidence, or adverse events. Definitive conclusions regarding fusion rate cannot be drawn due to low number of studies and unstandardized fusion definition.

Conclusion

Endo-LIF is an effective and safe alternative to conventional lumbar interbody fusion procedures. Evidence shortcomings may be addressed, and future randomized control trials may be performed to compare techniques and to validate results.

Promoting Regeneration in Degenerative Disc Disease

OBJECTIVE

The degenerative disc disease has a multifactorial etiology and mechanical stress is one of the most important etiological factor. The purpose of this study was to evaluate the intervertebral disc (IVD) after axial stress diminution from the point of view of its proteoglycan (PG) content, with preoteoglicans (PGs) being very important in the normal function but also in the degenerative or regenerative processes.

METHODS

This is a single-center, prospective, non-randomized study of 38 degenerated intervertebral discs treated with monosegmental or polisegmental posterior lumbar spinal fixation in 27 patients. During surgery, a posterior intervertebral distraction at operated levels was applied. Patients' mean age was 50.77 years and the mean follow-up 28.74 months. Both clinical (visual analog pain scale, Oswestry disability index) and radiological (lumbar spine lordosis, disc thickness) analyses were made before and after surgery. A new method of cartilage analysis, which was also validated for the IVD, delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) was used to determine the PG content before and after surgery for both the intervertebral degenerative disc and control level L1-L2 disc.

RESULTS

The clinical features improved significantly. The thickness of the operated discs increased by an average of 1.71 mm postoperatively and remained unchanged in the control group. The lumbar lordosis did not change significantly. In dGEMRIC studies, the discs accumulated in average 410.08 units /cm2 of gadolinium before surgery and 272.45 units/cm2 after surgery, without significant changes in the control group.

CONCLUSION

Our study shows an improvement of PG quantity in degenerated IVD due to a decrease in gadolinium binding seen in dGEMRIC study. Thus, we can ameliorate IVD homeostasis by eliminating mechanical stress, which could be a step towards the process of disc regeneration.

Evolution, Current Trends, and Latest Advances of Endoscopic Spine Surgery

Background: The aging of the population in developing and developed countries has led to a significant increase in the health burden of spinal diseases. These elderly patients often have a number of medical comorbidities due to aging. The need for minimally invasive techniques to address spinal disorders in this elderly population group cannot be stressed enough. Minimally invasive spine surgery (MISS) has several proven benefits, such as minimal muscle trauma, minimal bony resection, lesser postoperative pain, decreased infection rate, and shorter hospital stay. Methods: A comprehensive search of the literature was performed using PubMed. Results: Over the past 40 years, constant efforts have been made to develop newer techniques of spine surgery. Endoscopic spine surgery is one such subset of MISS, which has all the benefits of modern MISS. Endoscopic spine surgery was initially limited only to the treatment of lumbar disc herniation. With improvements in optics, endoscopes, endoscopic drills and shavers, and irrigation pumps, there has been a paradigm shift. Endoscopic spine surgery can now be performed with high magnification, thus allowing its application not only to lumbar spinal stenosis but also to spinal fusion surgeries and cervical and thoracic pathology as well. There has been increasing evidence in support of these newer techniques of spine surgery. Conclusions: For this report, we studied the currently available literature and outlined the historical evolution of endoscopic spine surgery, the various endoscopic systems and techniques available, and the current applications of endoscopic techniques as an alternative to traditional spinal surgery.

Epidural, Inadvertent Subdural, and Combined Epidural-Subdural Anesthesia in Lumbar Spine Surgery: A Retrospective Analysis

This study aimed to categorize contrast media images associated with epidural, subdural, and combined epidural-subdural anesthesia in patients who had undergone fluoroscopy-guided epidural anesthesia using contrast media combined with monitored anesthesia care (MAC) targeted at deep sedation, incorporating capnography over 5 years. Additionally, a correlation was established between the anesthetic effects and radiographic findings according to the categorized imaging appearances. This study included 628 patients who underwent endoscopic, open, or fusion surgery under epidural anesthesia at Nanoori Hospital in Gangnam between March 2018 and September 2023. Fluoroscopy-guided epidural anesthesia using contrast media combined with MAC and capnography was used. The dataset included detailed radiographic imaging, nursing, and anesthesia records. Distinct patterns of anesthesia administration were observed, with 49%, 19.6%, and 31% of patients receiving epidural, subdural, and combined epidural-subdural anesthesia, respectively. The incidence and duration of motor block were significantly different among the three groups. Additionally, subdural anesthesia displayed a higher incidence of motor block and a prolonged motor deficit duration than epidural anesthesia. Fluoroscopic guidance using a contrast medium for epidural and subdural anesthesia ensures precise space identification and prevents serious anesthetic complications. Our findings suggest the potential to achieve stable anesthesia, particularly using subdural and combined epidural-subdural anesthesia.

Exoscope Use in Spine Surgery: A Systematic Review of Applications, Benefits, and Limitations

BACKGROUND

Exoscopes were recently developed as an alternative to the operative microscope (OM) and endoscope for intraoperative visualization during neurosurgery. Prior reviews studying mixed cranial and spinal surgical cohorts reported advantages with exoscope use, including improved ergonomics and teaching. In recent years, there has been an increase in exoscope research, with no updated systematic review focused exclusively on the benefits and limitations of exoscope use in spine surgery. Thus, we sought to systematically synthesize the literature related to exoscope-assisted spine surgery.

METHODS

A literature search was conducted using the PubMed, Embase, Scopus, Cochrane, and Web of Science databases to identify relevant studies reported between 2010 and September 2023. Data, such as the exoscope model used, procedure types performed, and user observations, were then collected.

RESULTS

A total of 31 studies met our inclusion criteria, including 481 patients with spine pathologies who underwent a surgical procedure using 1 of 9 exoscope models. The lumbar region was the most frequently operated area (n = 234; 48.6%), and discectomies comprised the most overall procedures (n = 273; 56.8%). All patients benefited clinically. The reported advantages of exoscopes compared with OMs or endoscopes were improved focal distance, surgeon posture, trainee education, compactness, and assistant participation. Other aspects such as stereopsis, illumination, and cost had various observations.

CONCLUSIONS

Exoscopes have advantages compared with OMs or endoscopes during spine surgery. The user learning curve is minimal, and no negative patient outcomes have been reported. However, some aspects of exoscope use necessitate longer term prospective research before exoscopes can be considered a standard tool in the armamentarium of intraoperative visualization strategies.

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.

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.

Clinical efficacy of nucleoplasty for uncontained lumbar disc herniation: a retrospective study

BACKGROUND

There are insufficient in-depth studies on whether percutaneous lumbar nucleoplasty (PLN) is effective and safe for the treatment of uncontained lumbar disc herniation (ULDH). This study aimed to investigate the clinical efficacy of PLN on radiating leg pain caused by ULDH.

METHODS

Patients who underwent PLN for ULDH and met the inclusion criteria between June 2018 and July 2022 were included. Clinical outcomes were evaluated using the numeric rating scale (NRS) for radiating pain preoperatively; at 1 day, 1 week, and 1 month postoperatively; and at the last follow-up. Patient satisfaction was assessed using MacNab criteria.

RESULTS

Forty-one patients were enrolled. The mean age was 50.2 years (range 24-73 years). The mean and standard deviation of the preoperative NRS in 39 patients with radiating pain was 9.0 ± 1.2. The NRS scores at 1 day, 1 week, and 1 month postoperatively and at the last follow-up were 4.6 ± 3.2, 3.6 ± 3.3, 2.9 ± 3.2, and 1.4 ± 2.0, respectively, showing significant improvement (all, p < 0.001). The number of patients (percentage) with excellent or good satisfaction according to the MacNab criteria was 29 (70.7%). Major complications were not observed. Three patients underwent additional surgery after PLN because of persistent radiating pain.

CONCLUSIONS

PLN is a safe and feasible treatment option for ULDH. Treatment outcomes were favorable on average; however, the lack of consistency was a drawback.

Pros and Cons of Minimally Invasive Spine Surgery

This paper reviews current knowledge on minimally invasive spine surgery (MISS). Although it has significant advantages, such as less postoperative pain, short hospital stay, quick return to work, better cosmetics, and less infection rate, there are also disadvantages. The long learning curve, the need for special instruments and types of equipment, high costs, lack of tactile sensation and biplanar imaging, some complications that are hard to treat, and more radiation to the surgeon and surgical team are the disadvantages.Most studies remark that the outcomes of MISS are similar to traditional surgery. Although patients demand it more than surgeons, we predict the broad applications of MISS will replace most of our classical surgical approaches.

The Call for Neuroendoscopy Cadaveric Workshops in Lower-Middle Income Countries

OBJECTIVE

This study aims to assess the impact of the workshops organized during Neuroendocon 23 on the perspective and confidence of neurosurgeons toward endoscopy in a lower-middle income country.

METHODS

Neuroendocon 23 had cranial and spinal endoscopy cadaveric workshops with 30 delegates each. A pre and postworkshop survey was disseminated among the delegates, and statistical analysis was performed with SPSS (version 26) using P < 0.05.

RESULTS

A total of 24 delegates (40%) consented to participate in the study, with only 1 female respondent (4.17%). After the cranial endoscopy workshop, there was an increase in the level of confidence of delegates in cranial endoscopic approaches (P < 0.001). Similarly, after the spine endoscopy workshop, the respondents had increased confidence in managing spine conditions with the endoscopic approach (P = 0.040), to the extent that they preferred the endoscopic over the microsurgical technique (P < 0.001). All respondents (n = 24, 100%) believed that endoscopy should be promoted in lower-middle income countries and integrated into residency curricula.

CONCLUSIONS

Cranial and spinal endoscopy cadaveric workshops could be the first step in stimulating the interest of neurosurgeons in endoscopy.

CLAD-Net: cross-layer aggregation attention network for real-time endoscopic instrument detection

As medical treatments continue to advance rapidly, minimally invasive surgery (MIS) has found extensive applications across various clinical procedures. Accurate identification of medical instruments plays a vital role in comprehending surgical situations and facilitating endoscopic image-guided surgical procedures. However, the endoscopic instrument detection poses a great challenge owing to the narrow operating space, with various interfering factors (e.g. smoke, blood, body fluids) and inevitable issues (e.g. mirror reflection, visual obstruction, illumination variation) in the surgery. To promote surgical efficiency and safety in MIS, this paper proposes a cross-layer aggregated attention detection network (CLAD-Net) for accurate and real-time detection of endoscopic instruments in complex surgical scenarios. We propose a cross-layer aggregation attention module to enhance the fusion of features and raise the effectiveness of lateral propagation of feature information. We propose a composite attention mechanism (CAM) to extract contextual information at different scales and model the importance of each channel in the feature map, mitigate the information loss due to feature fusion, and effectively solve the problem of inconsistent target size and low contrast in complex contexts. Moreover, the proposed feature refinement module (RM) enhances the network's ability to extract target edge and detail information by adaptively adjusting the feature weights to fuse different layers of features. The performance of CLAD-Net was evaluated using a public laparoscopic dataset Cholec80 and another set of neuroendoscopic dataset from Sun Yat-sen University Cancer Center. From both datasets and comparisons, CLAD-Net achieves the A P 0.5 of 98.9% and 98.6%, respectively, that is better than advanced detection networks. A video for the real-time detection is presented in the following link: https://github.com/A0268/video-demo.

Relationship Between Types of Warming Devices and Surgical Site Infection in Patients Who Underwent Posterior Fusion Surgery Based on National Data

OBJECTIVE

Perioperative hypothermia can lead to various complications. Although various warming techniques have been used to prevent perioperative hypothermia, the effect of these techniques on surgical site infection (SSI) during posterior fusion surgery is unclear. The effects of warming devices on SSI rates were therefore analyzed using data complied by the Health Insurance and Review Assessment (HIRA) Service in Korea.

METHODS

This study included 5,406 patients in the HIRA Service database who underwent posterior fusion surgery during the years 2014, 2015, and 2017. Factors related to SSI in these patients, including warming devices, antibiotics, and transfusion, were analyzed.

RESULTS

The incidence of SSI was higher in patients who underwent forced air warming than in those who did not undergo active warming (odds ratio [OR], 1.73; p = 0.039), especially above 70 years old (OR, 4.11; p = 0.014). By contrast, the incidence of SSI was not significantly higher in patients who underwent device using conduction. Infection rates were higher in patients who received prophylactic antibiotics within 20 minutes before incision, than within 21 to 60 minutes (OR, 2.07; p = 0.001) and who received more blood transfusions (1 pint < volume ≤ 2 pint; OR, 1.75; p = 0.008, > 2 pint; OR, 2.73; p = 0.004).

CONCLUSION

SSI rates were higher in patients who underwent warming with forced air devices than with devices using conduction, as well as being higher in patients who older age, received blood transfusions and administered antibiotics within 20 minutes before incision. Devices using conduction have more advantages in preventing SSI than forced air warming device. In addition, the reduction of other risk factors for SSI may improve postoperative results.

Saving Stabilizing Structure Treatment With Bilateral-Contralateral Decompression for Spinal Stenosis in Degenerative Spondylolisthesis Using Unilateral Biportal Endoscopy

OBJECTIVE

This study aimed to evaluate the treatment of spinal stenosis with spondylolisthesis using bilateral-contralateral unilateral biportal endoscopic (UBE) decompression to minimize facet joint damage.

METHODS

We retrospectively evaluated 42 patients with grade 1 spondylolisthesis who underwent bilateral-contralateral UBE decompression between July 2018 and September 2019. To identify segmental instability, static and dynamic images from preoperative and postoperative procedures and final follow-up radiographs were reviewed. Lateral radiograph slippage ratio, sagittal motion, and facet joint preservation were evaluated. Clinical assessments were conducted using the visual analogue scale (VAS), Oswestry Disability Index (ODI), and modified MacNab criteria.

RESULTS

The average final follow-up period was 26.5 ± 1.3 months. The average preoperative slip percentage was 15.70% ± 5.25%, which worsened to 18.80% ± 5.41% at the final follow-up (p < 0.005). The facet joint preservation rate was 95.6% ± 4.1% on the contralateral side. Improvements in the VAS scores (leg pain: from 7.9 ± 2.2 to 3.1 ± 0.7; p < 0.005; back pain: from 7.2 ± 3.0 to 2.8 ± 1.0; p < 0.005) were observed at the final follow-up. The mean preoperative ODI was 26.19 ± 3.42, which improved to 9.6 ± 1.0 (p < 0.005). Thirteen patients exhibited delayed focal segmental instability following decompression. Despite the absence of symptoms or improvement with conservative treatment in the majority of patients with delayed instability, two patients required fusion surgery to address the instability. Additionally, 2 patients developed facet synovial cysts, while 2 experienced spinous process fractures.

CONCLUSION

Bilateral decompression with a contralateral UBE approach could be an effective and alternative treatment method to reduce instability in spinal stenosis with grade 1 spondylolisthesis.

An algorithm for selection of full endoscopic approach for symptomatic nerve root decompression

Background Context

Both Transforaminal (TF) and Interlaminar (IL) endoscopic approaches are established techniques of decompression for lumbar compressive radiculopathy. In the absence of adequate literature, there is always some dilemma in selecting the approach for endoscopic decompression leading to long learning curves and high chances of inadequate decompression, iatrogenic instability, dural tear, or dysesthesia. Hence authors propose a new surgical nomenclature and algorithm for selection of endoscopic approach.

Methods

This retrospective study included 396 of 626 consecutive patients who met the inclusion criteria, who underwent either TF (n=302) or IL (n=202) full endoscopic spine surgery. MRI findings of every patient were classified as per FAPDIS (Facet angle, Anterior pathology, Posterior pathology, Dorsal, Inferior, and Superior migration) algorithm. Inter-observer variations were calculated. The targeted nomenclature was used to define the selection of endoscopic TF or IL approach for symptomatic nerve root decompression. All patients were followed up for preop and postop 6 months VAS and Oswestry Disability Index score for validation of FAPDIS algorithm.

Results

Median age: 46.8 years; Sides and levels operated 330 single-level ipsilateral, 54 multiple-level ipsilateral, 6 single-level bilateral, and 6 multiple-level bilateral. Interobserver agreement in the selection of TF approach was 0.873 and IL approach was 0.882. Interobserver variability was also calculated for each FAPDIS factor, selection of P3 and P4 pathology was the main reason for disagreement. All other FAPDIS factors show good to excellent correlation. The overall VAS score decreased from a preoperative value of 9 to 1 at 6 months follow-up (p-value < 0.001), and the overall Oswestry Disability Index score improved from 89 to 12 (p-value <.001).

Conclusions

The author's new FAPDIS surgical nomenclature and algorithm is a reliable tool for describing the symptomatic nerve root compression for the selection of endoscopic surgical approach to achieve adequate decompression of offending neural structure with minimum challenges to minimize perioperative complication rate.

Unilateral Bi/Multi-Portal Endoscopy for the Treatment of Complicated Lumbar Degenerative Diseases with Utilization of Uniaxial Spinal Endoscope, Instead of Arthroscope: Technique Note and Clinical Results

Objective

This article aims to discuss a novel surgical strategy, referred to as unilateral bi/multi-portal endoscopy (UME), which used a uniaxial spinal endoscope instead of an arthroscope in the traditional unilateral biportal endoscopy (UBE) surgical procedure in our study of the treatment of complicated lumbar degenerative diseases.

Methods

This retrospective study included 42 patients diagnosed with high-migrated lumbar disc herniation and bilateral spinal stenosis who underwent UME surgery from January 2021 to December 2021. Patients included 20 men and 22 women, with an average age of 55.97±14.92 years. The average follow-up period was 13.19 months. The demographic data, operation time (min), and complications were recorded and analyzed. The visual analogue scale (VAS), Oswestry Disability Index (ODI) scores were used to evaluate the surgical outcomes. Three-dimensional CT scans and MRI were conducted to evaluate the radiographic improvement.

Results

A total of 26 patients were diagnosed with lumbar disc herniation and 16 with lumbar spinal stenosis. All 42 patients underwent UME surgery and achieved satisfactory outcomes. The operation time was 154.46±46.09 min. The average follow-up time was 13.19±1.33 months. The preoperative back pain (VAS-Back) and the last follow-up VAS-Back were 3.84±1.00 and 0.70±0.46, respectively (P < 0.05). The preoperative leg pain (VAS-Leg) and the last follow-up VAS-Leg were 6.46±1.08 and 1.03±0.64, respectively (P <0.05). Significant differences existed between preoperative ODI scores (58.70±11.22%) and the last follow-up ODI scores (9.24±3.04%; P<0.05). All patients achieved significant pain relief and functional improvement after the surgery. No severe complications occurred, except for two cases of postoperative dysesthesia and one case suffered from vertebral compression fractures induced by a postoperative accidental injury. Symptoms of numbness disappeared within one week with treatment using dexamethasone and neurotrophic drugs. The vertebral fracture case recovered with percutaneous kyphoplasty treatment.

Conclusion

This study suggests that UME is a promising treatment strategy for high-migrated disc herniation and bilateral spinal stenosis.

Clinical outcomes of uniportal compared with biportal endoscopic decompression for the treatment of lumbar spinal stenosis: a systematic review and meta-analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

Lumbar spinal stenosis (LSS) treatment has evolved with the introduction of minimally invasive surgery (MIS) techniques. Endoscopic methods take the concepts applied to MIS a step further, with multiple studies showing that endoscopic techniques have outcomes that are similar to those of more traditional approaches. The aim of this study was to perform an updated meta-analysis and systematic review of studies comparing the outcomes between both available endoscopic techniques (uni and biportal) for the treatment of LSS.

METHODS

Following PRISMA guidelines, we conducted a systematic literature search and compared the randomized controlled trials and retrospective studies of uniportal and biportal endoscopy in the treatment of LSS from several databases. Bias was assessed using quality assessment criteria and funnel plots. Meta-analysis using a random-effects model was used to synthesize the metadata. The authors used Review Manager 5.4 to manage the date and perform the review.

RESULTS

After a preliminary selection of 388 studies from electronic databases, the full inclusion criteria were applied; three studies were found to be eligible for inclusion. There were 184 patients from three unique studies. Meta-analysis of visual analog scale score for low back pain and leg pain showed no significant difference at the final follow-up (P = 0.51 and P = 0.66). ODI score after biportal surgery was lower than uniportal surgery [SMD = 0.34, 95% CI (0.04, 0.63), P = 0.02]. The mean operation time was similar in the unilateral biportal endoscopy (UBE) and uniportal groups (P = 0.53). The UBE group was associated with a shorter length of hospital stay (P = 0.05). Complications were similar in both groups (P = 0.89).

CONCLUSIONS

Current evidence shows no significant differences in most clinical outcomes between uniportal and biportal surgery. UBE may have a better ODI score at the end of the follow-up compared to uniportal. Further studies are required before drawing a definite conclusion.

STUDY REGISTRATION

PROSPERO prospective register of systematic reviews: Registration Nº. CRD42022339078, Available from: https://www.crd.york.ac.uk/prospero/displayrecord.php?ID=CRD42022339078.

Minimally Neural Retractive, Total Annular Resection, Transforaminal Endoscopic (TARTE) Approach for Severely Canal Compromising Lumbar Disk Herniation Accompanied by a Neurologic Deficit

OBJECTIVE

 Treatment of severely canal compromising lumbar disk herniations (LDH), occupying more than 50% of the canal area, are associated with technical difficulty and worse outcomes. This study aimed to describe new techniques of transforaminal endoscopic lumbar diskectomy (TELD) with less neural retraction, and total annular resection for broad-based severely canal compromising disk herniation. We also evaluated the feasibility and safety of the techniques, and analyzed the clinical and radiologic outcomes of 32 patients presenting with neurologic deficits.

METHODS

 A retrospective cohort study was performed with 32 consecutive patients who underwent TELD for broad-based severely canal compromising LDH between January 2018 and January 2020. We removed the LDH using two novel techniques: (1) the "mobile outside-in" approach and total annular resection method and (2) internal decompression and subsequent pushdown method of the migrated fragment. The cross-sectional area (CSA) on magnetic resonance image was evaluated preoperatively and compared with the postoperative image within 7 days and between 6 months and 1 year. The visual analog scale (VAS) for back and leg pain, Oswestry disability index (ODI), MacNab's criteria, and motor power of the involved lower extremities were evaluated pre- and postoperatively.

RESULTS

 A total of 32 patients, with an average age of 37.5 years (range: 17-66), underwent surgery. The mean VAS score for back pain improved from 7.84 ± 1.02 to 1.31 ± 0.54 and the ODI score improved from 74.3 ± 7.82 to 20.4 ± 3.71 at final follow-up. According to MacNab's criteria, 23 patients had excellent and 9 patients had good outcomes at final follow-up. All patients operated on at the L4-L5 level had great toe/ankle dorsiflexion and/or ankle plantar flexion weakness; knee extension weakness was found at the L2-L3 and L3-L4 levels. Motor function improved significantly; the mean values and range preoperatively, and at 1 month, 3 months, and final follow-up, were 3.41 ± 0.95 (1-4), 4.56 ± 0.56 (3-5), 4.88 ± 0.34 (4-5), and 4.97 ± 0.18 (4-5), respectively (p < 0.001, at all follow-up). The mean values and range of the preserved CSA proportion, preoperatively and within 1 week after surgery, and at final follow-up were 34.9 ± 10.9 (15-61), 81.06 ± 10.24 (63-97), and 93.03 ± 5.37 (76-99), respectively (p < 0.001, at all follow-up).

CONCLUSION

 The transforaminal endoscopic approach for broad-based severely canal compromising LDH can be considered a feasible surgical option for an experienced surgeon. With total annular resection and pushdown of migrated fragments, safe and complete removal of LDH was possible in patients with a neurologic deficit. Total annular resection may increase the overall but not the early recurrence rate.

Development of an Endoscopic Spine Surgery Program: Overview and Basic Considerations for Implementation

Endoscopic spine surgery (ESS) is an innovative technique allowing for minimally invasive, direct visualization of spinal abnormalities. The growth of ESS in the United States has been stunted by high start-up costs, low reimbursement rates, and the steep learning curve associated with mastering endoscopic techniques. Hergrae, we describe the current state and future direction of ESS and provide key action items for ESS program implementation.

Inpainting surgical occlusion from laparoscopic video sequences for robot-assisted interventions

Purpose

Medical technology for minimally invasive surgery has undergone a paradigm shift with the introduction of robot-assisted surgery. However, it is very difficult to track the position of the surgical tools in a surgical scene, so it is crucial to accurately detect and identify surgical tools. This task can be aided by deep learning-based semantic segmentation of surgical video frames. Furthermore, due to the limited working and viewing areas of these surgical instruments, there is a higher chance of complications from tissue injuries (e.g., tissue scars and tears).

Approach

With the aid of digital inpainting algorithms, we present an application that uses image segmentation to remove surgical instruments from laparoscopic/endoscopic video. We employ a modified U-Net architecture (U-NetPlus) to segment the surgical instruments. It consists of a redesigned decoder and a pre-trained VGG11 or VGG16 encoder. The decoder was modified by substituting an up-sampling operation based on nearest-neighbor interpolation for the transposed convolution operation. Furthermore, these interpolation weights do not need to be learned to perform upsampling, which eliminates the artifacts generated by the transposed convolution. In addition, we use a very fast and adaptable data augmentation technique to further enhance performance. The instrument segmentation mask is filled in (i.e., inpainted) by the tool removal algorithms using the previously acquired tool segmentation masks and either previous instrument-containing frames or instrument-free reference frames.

Results

We have shown the effectiveness of the proposed surgical tool segmentation/removal algorithms on a robotic instrument dataset from the MICCAI 2015 and 2017 EndoVis Challenge. We report a 90.20% DICE for binary segmentation, a 76.26% DICE for instrument part segmentation, and a 46.07% DICE for instrument type (i.e., all instruments) segmentation on the MICCAI 2017 challenge dataset using our U-NetPlus architecture, outperforming the results of earlier techniques used and tested on these data. In addition, we demonstrated the successful execution of the tool removal algorithm from surgical tool-free videos that contained moving surgical tools that were generated artificially.

Conclusions

Our application successfully separates and eliminates the surgical tool to reveal a view of the background tissue that was otherwise hidden by the tool, producing results that are visually similar to the actual data.

Clinical and Radiological Outcomes of a Comparative Study of Anterior Cervical Decompression and Fusion with Partial Pediculotomy, Partial Vertebrotomy (PPPV) Posterior Endoscopic Cervical Decompression (PECD) for Cervical Foraminal Pathology

Background and Objectives: The purpose was to compaSre medium-term clinical and radiological outcomes of Partial Pediculotomy, Partial Vertebrotomy (PPPV) Posterior Endoscopic Cervical Decompression (PECD) surgery versus Anterior Cervical Discectomy and Fusion (ACDF) for patients with cervical disc herniations and foraminal pathologies. Materials and Methods: A prospective registry of patients who had undergone either PPPV PECD surgery or ACDF surgery for cervical disc herniation or foraminal pathologies under a single fellowship-trained spine surgeon was performed. The baseline characteristics and operative details including complications were recorded for all included patients. The clinical outcomes evaluated include VAS, MJOA, motor score, and NDI and MacNab's score. The radiological parameters in neutral-measured facet length, facet area, disc height, C2-C7 angle, neck tilt angle, T1 slope and thoracic inlet angle were also evaluated. Results: A total of 55 patients (29 PPPV PECD, 26 ACDF) were included, with mean follow-up periods of 21.9 and 32.3 months, respectively. Each cohort was noted to have a single case of surgical complication. Statistically significant changes of facet area (49.05 ± 14.50%) and facet length (52.71 ± 15.11%) were noted in the PPPV PECD group. At neutral alignment of the neck on a lateral X-ray, compared to ACDF, PPPV PECD had a statistically significant change in neck tilt angle (-11.68 ± 17.35°) and T1 slope angle (-11.69 ± 19.58°). Whilst both PPPV PECD and ACDF had significant improvements in VAS, MJOA and NDI postoperatively, PPPV PECD was found to be superior across all above scores at various follow-up timepoints compared to its ACDF counterparts. Conclusions: PPPV PECD surgery achieved a satisfactory radiological correction of neck alignment and significantly improved clinical outcomes at medium-term follow-up for our cohort of patients, highlighting its feasibility in treating patients with cervical disc herniations and foraminal pathologies.

Awake transforaminal endoscopic lumbar discectomy in an ambulatory surgery center: early clinical outcomes and complications of 100 patients

PURPOSE

Transforaminal endoscopic discectomy has been found to have equivalent outcomes to traditional discectomy techniques. Controversy exists concerning whether this should be performed under general anesthetic with neuromonitoring or can be safely performed on awake patients without neuromonitoring. This study aimed to evaluate the safety and effectiveness of awake transforaminal endoscopic discectomy in an ambulatory setting.

METHODS

100 consecutive patients with lumbar disc herniations treated with transforaminal endoscopic discectomy by a single surgeon were enrolled in the study. All procedures were performed under conscious sedation with local anesthetic. Preoperative and postoperative visual analog scale (VAS) scores were recorded and compared. Time spent in recovery prior to discharge home and complications were also recorded.

RESULTS

Average VAS score improved from a mean of 6.85 to 0.74 (median 7 to 0) immediately postoperatively. The average time spent in Post Anesthesia Care Unit (PACU) prior to discharge was 56.7 min. Average VAS score at 2 weeks was 3.07 (median 2.5). Complication rates were commensurate with published results in the literature. The most common complication was radiculitis, which appears to be more likely with foraminal/extraforaminal herniations at a rate of 20.7%, versus 2.6% for central/paracentral herniations. There were no cases that required conversion to general anesthetic or transfer to a hospital and no permanent nerve injuries in this cohort.

CONCLUSIONS

Endoscopic discectomy can safely and successfully be performed in an ambulatory surgery center under conscious sedation and local anesthetic without neuromonitoring. This procedure leads to rapid recovery in the PACU and significantly improved VAS scores postoperatively.

LEVEL OF EVIDENCE

Level IV.

Less correction with minimally invasive surgery for adolescent idiopathic scoliosis compared to open surgical correction

PURPOSE

In this study, we investigated the relationship between the results of thoracic curve correction using minimally invasive surgeries in 35 patients and open surgical correction in 47 patients with adolescent idiopathic scoliosis.

METHODS

The correlations between the Cobb's angle of the primary and postoperative curves, angle of thoracic kyphosis and lumbar lordosis, correction percentage, derotation values, estimated blood loss, duration of surgery, and period of hospitalization after surgery were assessed by calculating the mean and standard deviation. Calculation and comparison were performed using Pearson correlation.

RESULTS

The Cobb's angle correction ranged from 53.4° ± 11.8° to 6.7° ± 5.2° (p < 0.001) in the open surgical correction group and from 51.2° ± 11.4° to 11.7° ± 5.8° (p < 0.001) in the minimally invasive surgery group before and after surgery, respectively. The percentage of curvature correction was 88.2% ± 8.0% and 77.7% ± 10.7% (p < 0.001) in the open surgical correction and minimally invasive surgery groups, respectively. The estimated blood loss was higher in the open surgical correction group than in the minimally invasive surgery group (208.7 ± 113.4 vs 564.3 ± 242.7 mL). Axial rotation was changed from 29.1°± 7.5 to 17.1°± 6.8 (p < 0.001) in the open surgical correction group and from 28.9°± 7.8 to 19.4°± 6.4 (p < 0.001) in the minimally invasive surgery group. The duration of surgery was shorter in the open surgical correction group than in the minimally invasive surgery group (266.6 ± 64.3 vs 346.2 ± 70.5 min). A positive correlation between time of operation and Cobb's angle correction (in °) in open surgical correction (r = 0.37) and minimally invasive surgery (r = 0.43) was found.

CONCLUSION

The open surgical correction procedures were more effective than minimally invasive surgery in correcting the spinal curve. The increase in the duration of open surgical correction increases the estimated blood loss, but it also more significantly improves the correction of Cobb's angle.

LEVEL OF EVIDENCE

III.

Less correction with minimally invasive surgery for adolescent idiopathic scoliosis compared to open surgical correction

Purpose:

In this study, we investigated the relationship between the results of thoracic curve correction using minimally invasive surgeries in 35 patients and open surgical correction in 47 patients with adolescent idiopathic scoliosis.

Methods:

The correlations between the Cobb’s angle of the primary and postoperative curves, angle of thoracic kyphosis and lumbar lordosis, correction percentage, derotation values, estimated blood loss, duration of surgery, and period of hospitalization after surgery were assessed by calculating the mean and standard deviation. Calculation and comparison were performed using Pearson correlation.

Results:

The Cobb’s angle correction ranged from 53.4° ± 11.8° to 6.7° ± 5.2° ( p < 0.001) in the open surgical correction group and from 51.2° ± 11.4° to 11.7° ± 5.8° ( p < 0.001) in the minimally invasive surgery group before and after surgery, respectively. The percentage of curvature correction was 88.2% ± 8.0% and 77.7% ± 10.7% ( p < 0.001) in the open surgical correction and minimally invasive surgery groups, respectively. The estimated blood loss was higher in the open surgical correction group than in the minimally invasive surgery group (208.7 ± 113.4 vs 564.3 ± 242.7 mL). Axial rotation was changed from 29.1°± 7.5 to 17.1°± 6.8 ( p < 0.001) in the open surgical correction group and from 28.9°± 7.8 to 19.4°± 6.4 ( p < 0.001) in the minimally invasive surgery group. The duration of surgery was shorter in the open surgical correction group than in the minimally invasive surgery group (266.6 ± 64.3 vs 346.2 ± 70.5 min). A positive correlation between time of operation and Cobb’s angle correction (in °) in open surgical correction ( r = 0.37) and minimally invasive surgery ( r = 0.43) was found.

Conclusion:

The open surgical correction procedures were more effective than minimally invasive surgery in correcting the spinal curve. The increase in the duration of open surgical correction increases the estimated blood loss, but it also more significantly improves the correction of Cobb’s angle.

Level of evidence:

III.

Unilateral Biportal Endoscopy for Lumbar Spinal Stenosis and Lumbar Disc Herniation

Background

Unilateral biportal endoscopy (UBE) is a novel minimally invasive technique for the treatment of lumbar spinal stenosis and lumbar disc herniations. Uniportal endoscopy was utilized prior to the advent of UBE and has been considered the workhorse of endoscopic spine surgery (ESS) for lumbar discectomy and decompressive laminectomy. However, there are theoretical advantages to UBE compared with traditional uniportal endoscopy, including that the procedure utilizes typical spinal equipment that should be readily available, requires less capital cost and optical instrumentation, and provides greater operative flexibility as a result of utilizing both a working and a viewing portal7,8.

Description

A 0-degree arthroscope is typically utilized for discectomy and lumbar laminectomies. The use of a radiofrequency ablator is critical to help coagulate osseous and muscle bleeders. For irrigation, gravity or a low-pressure pump, typically <40 mm Hg, can be utilized9,10. Further details regarding irrigation pressure are provided in "Important Tips." The use of a standard powered burr is typical to help osseous decompression, and Kerrison ronguers, pituitaries, osteotomes, and probes utilized in open or tubular cases suffice. Two incisions are made approximately 1 cm lateral to the midline. If working from the left side for a right-handed surgeon, the working portal is typically made at the lower laminar margin of the target level. The camera portal is then made typically 2 to 3 cm cephalad. A lateral radiograph is then utilized to confirm the portal placements. From the right side, the working portal is cephalad and the camera portal is caudal. Because of the switch, the portals may be shifted more distally.The first step is creating a working space because there is no true joint space in the spine. With use of radiofrequency ablation, a working space is created in the interlaminar space. Next, with use of a powered burr or a chiseled osteotomy, the base of the cephalad spinous process is thinned until the insertion of the ligamentum flavum is found. Next, the ipsilateral and contralateral laminae are thinned in a similar fashion. Once the osseous elements are removed, the ligamentum flavum is removed en bloc. The traversing nerve roots are checked under direct high-magnification visualization to ensure that they are decompressed. If a discectomy is necessary, standard nerve-root retractors can be utilized to retract the neural elements. With use of a blunt-tip elevator, the anular defect can be incised and the herniated disc can be removed under direct high-power visualization. In addition, a small curet can be utilized to create a defect in the weakened anulus or membrane covering the extruded disc material in order to help deliver the herniated disc material. Epidural veins are coagulated typically with use of a fine-point bipolar radiofrequency device.

Alternatives

Nonoperative treatments include oral anti-inflammatory drugs, physical therapy, and epidural injections; if these fail, alternative surgical treatments include open lumbar laminectomy and/or discectomy, tubular lumbar laminectomy and/or discectomy, and other minimally invasive techniques, such as microendoscopy, uniportal endoscopy, and microscopy-assisted decompression.

Rationale

UBE is a minimally invasive surgical procedure that better preserves osseous and muscular structure compared with open and tubular techniques. Conventional lumbar laminectomy involves dissection and retraction of the multifidus muscle from the spinous process to the facet joint. This exposure can damage the delicate posterior dorsal rami. Long retraction time can also lead to pressure-induced muscle atrophy and potentially increased chronic low back pain. Alternatively, smaller incisions and shorter hospital stays are possible with UBE.Similar to UBE, tubular surgery can minimize soft-tissue damage compared with open techniques; however, in a randomized trial assessing techniques for spinal stenosis surgery, Kang et al. found that UBE and tubular surgery had similarly favorable clinical outcomes at 6 months postoperatively but UBE resulted in decreased operative time, drain output, opiate use, and length of hospital stay5.Furthermore, the use of an endoscope in the biportal technique allows ultra-high magnification of the spinal pathology, decreased capital costs, and the ability to use 2 hands with freedom of movement. UBE provides clear visualization of the neural elements while keeping maximal ergonomic efficiency with the surgeon's head looking straight forward, the shoulders relaxed, and the elbows bent to 90°. Continuous irrigation through the endoscope also helps with bleeding and decreasing the risk of infection.

Expected Outcomes

Long-term outcomes do not differ substantially between discectomies performed with use of the presently described technique and procedures done with more traditional minimally invasive (i.e., tubular) techniques; however, visual analogue scale scores for back pain may be better in the short term, and there is evidence of a shorter hospital stay with UBE2. Complication rates did not differ from other minimally invasive techniques. When comparing UBE and stenosis, Aygun and Abdulshafi found that UBE was associated with decreased hospital stays, operative time, and blood loss and better clinical outcomes up to 2 years postoperatively compared with tubular laminectomy12.

Important Tips

The optimal hydrostatic pressure is 30 to 50 mm Hg. Pressure is determined by the distance between the fluid source and the working space. Because the working space does not change, the height of the bag decides pressure. A simple formula for pressure is calculated by dividing the distance from the working field to the irrigation source by 1.36. A rule of thumb is that if the bag is 50 to 70 cm above the patient's back, the pressure should be adequate. The advantages of using gravity rather than a pressure pump are that excessive fluid solution pressure in the epidural space can cause neurological issues such as nuchal pain, headache, and seizure11. Additionally, if the intertransverse membrane or the lateral margins of the disc are violated, hydroperitoneum can occur unknowingly due to the high-pressure system.Gravity or pump pressure of >40 mm Hg may elevate epidural pressure and mask operative bleeding. When the pump is turned off at the end of the surgical procedure, a postoperative epidural hematoma may occur because the bleeding source may not have been recognized while the pump pressure was on.Excessive pump pressure may lead to an increase in intracranial pressure, causing headache or delayed recovery from general anesthesia with stiff posture and hyperventilation.Make sure fluid is emerging from the working portal and the muscle area is not swelling to prevent soft-tissue fluid extravasation.Epidural veins are coagulated typically with a fine-point bipolar radiofrequency device.Osseous bleeding can be controlled with bone wax or a high-speed burr.

Acronyms and Abbreviations

MRI = magnetic resonance imagingRF = radiofrequencyAP = anteroposterior.

Advancing Education in Endoscopic Spinal Navigation: Novel Methods and Technical Note

This report aims to demonstrate how to teach anatomy and understanding of spinal endoscopic vision and navigation using mnemonics. The authors present a new surgical technique for teaching endoscopic spinal navigation in a didactic manner with tips such as the "rule of the hand" and decomposition of the endoscopic navigation movement. We demonstrate how the surgery is seen and illustrate how images are projected onto the screen, then divide the navigation into spatial orientation and self-navigation. The article describes the proper puncture technique, how to introduce the working portal, and how to assimilate this new anatomical vision using the "rule of the hand." The surgeon projects their hand on the video screen to guide themselves when starting the navigation and uses the same technique to localize regions of interest during surgery. Finally, the authors break down the navigational movement into three components: forceps positioning, triangulation, and joystick motion. One of the biggest challenges when learning spinal endoscopic surgery is understanding the anatomy seen through the endoscope. By decomposing movements required for navigation, one can understand how to make proper use of the equipment as well as improve their knowledge of this "new anatomy." The learning methods taught in this article have the potential to decrease the learning curve and radiation exposure to those that are still acquainting themselves to spinal endoscopic navigation. We recommend that further studies measure and quantify the impact of these methods on surgical practice.

The Role and Future of Endoscopic Spine Surgery: A Narrative Review

Many types of surgeries are changing from conventional to minimally invasive techniques. Techniques in spine surgery have also changed, with endoscopic spine surgery (ESS) becoming a major surgical technique. Although ESS has advantages such as less soft tissue dissection and normal structure damage, reduced blood loss, less epidural scarring, reduced hospital stay, and earlier functional recovery, it is not possible to replace all spine surgery techniques with ESS. ESS was first used for discectomy in the lumbar spine, but the range of ESS has expanded to cover the entire spine, including the cervical and thoracic spine. With improvements in ESS instruments (optics, endoscope, endoscopic drill and shaver, irrigation pump, and multiportal endoscopic), limitations of ESS have gradually decreased, and it is possible to apply ESS to more spine pathologies. ESS currently incorporates new technologies, such as navigation, augmented and virtual reality, robotics, and 3-dimentional and ultraresolution visualization, to innovate and improve outcomes. In this article, we review the history and current status of ESS, and discuss future goals and possibilities for ESS through comparisons with conventional surgical techniques.

Retrospective Case Control Study: Clinical and Computer Tomographic Fusion and Subsidence Evaluation for Single Level Uniportal Endoscopic Posterolateral Approach Transforaminal Lumbar Interbody Fusion Versus Microscopic Minimally Invasive Transforaminal Interbody Fusion

STUDY DESIGN

Retrospective comparative study.

OBJECTIVE

Assessment of difference in clinical and computer tomographic outcomes between the 2 cohorts.

METHODS

Computer tomographic evaluation by Bridwell's grade, Kim's stage, Kim's subsidence grade and clinical evaluation by VAS, ODI and McNab's criteria on both cohorts.

RESULTS

33 levels of Endo-TLIF and 22 levels of TLIF were included, with a mean follow up of 14.3 (10-24) and 22.9 (13-30) months respectively. Both Endo-TLIF and TLIF achieved significant improvement of pain and ODI at post-operative 4 week, 3 months and at final follow up with VAS 4.39 ± 0.92, 5.27 ± 1.16 and 5.73 ± 1.21in Endo-TLIF and 4.55 ± 1.16, 5.05 ± 1.11 and 5.50 ± 1.20 in TLIF respectively and ODI at post-operative 1 week, 3 months and final follow up were 43.15 ± 6.57, 49.27 ± 8.24 and 51.73 ± 9.09 in Endo-TLIF and 41.73 ± 7.98, 46.18± 8.46 and 49.09 ± 8.98 in TLIF respectively, P < 0.05. Compared to TLIF, Endo-TLIF achieved better VAS with 0.727 ± 0.235 at 3 months and 0.727 ± 0.252 at final follow up and better ODI with 3.88 ± 1.50 at 3months and 3.42 ± 1.63 at final follow up, P < 0.05. At 6 months radiological evaluation comparison of the Endo-TLIF and TLIF showed significant with more favorable fusion rate in Endo-TLIF of -0.61 ± 0.12 at 6 months and -0.49 ± 0.12 at 1 year in Bridwell's grading and 0.70 ± 0.15 at 6 months and 0.56 ± 0.14 at 1 year in Kim's stage.There is less subsidence of 0.606 ± 0.18 at 6 months and -0.561 ± 0.20 at 1 year of Kim's subsidence grade, P < 0.05.

CONCLUSION

Application of single level uniportal endoscopic posterolateral lumbar interbody fusion achieved better clinical outcomes and fusion rate with less subsidence than microscopic minimally invasive transforaminal lumbar interbody fusion in mid-term evaluation for our cohorts of patients.

Case-matched radiological and clinical outcome evaluation of interlaminar versus microsurgical decompression of lumbar spinal stenosis

PURPOSE

Endoscopic spine surgery is a globally expanding technique advocated as less invasive for spinal stenosis treatment compared to the microsurgical approach. However, evidence on the efficiency of interlaminar full-endoscopic decompression (FED) vs. conventional microsurgical decompression (MSD) in patients with lumbar spinal stenosis is still scarce. We conducted a case-matched comparison for treatment success with consideration of clinical, laboratory, and radiologic predictors.

METHODS

We included 88 consecutive patients (FED: 36/88, 40.9%; MSD: 52/88, 59.1%) presenting with lumbar central spinal stenosis. Surgery-related (operation time, complications, length of stay (LOS), American Society of Anesthesiologists physical status (ASA) score, C-reactive protein (CRP), white blood cell count, side of approach (unilateral/bilateral), patient-related outcome measures (PROMs) (Oswestry disability index (ODI), numeric rating scale of pain (NRS; leg-, back pain), EuroQol questionnaire (eQ-5D), core outcome measures index (COMI)), and radiological (dural sack cross-sectional area, Schizas score (SC), left and right lateral recess heights, and facet angles, respectively) parameters were extracted at different time points up to 1-year follow-up. The relationship of PROMs was analyzed using Spearman's rank correlation. Surgery-related outcome parameters were correlated with patient-centered and radiological outcomes utilizing a regression model to determine predictors for propensity score matching.

RESULTS

Complication (most often residual sensorimotor deficits and restenosis due to hematoma) rates were higher in the FED (33.3%) than MSD (13.5%) group (p < 0.05), while all complications in the FED group were observed within the first 20 FED patients. Operation time was higher in the FED, whereas LOS was higher in the MSD group. Age, SC, CRP revealed significant associations with PROMs. We did not observe significant differences in the endoscopic vs. microsurgical group in PROMs. The correlation between ODI and COMI was significantly high, and both were inversely correlated with eQ-5D, whereas the correlations of these PROMs with NRS findings were less pronounced.

CONCLUSIONS

Endoscopic treatment of lumbar spinal stenosis was similarly successful as the conventional microsurgical approach. Although FED was associated with higher complication rates in our single-center study experience, the distribution of complications indicated surgical learning curves to be the main factor of these findings. Future long-term prospective studies considering the surgical learning curve are warranted for reliable comparisons of these techniques.

Remodeling of Epidural Fluid Hematoma after Uniportal Lumbar Endoscopic Unilateral Laminotomy with Bilateral Decompression: Comparative Clinical and Radiological Outcomes with a Minimum Follow-up of 2 Years

STUDY DESIGN

Retrospective cohort study.

PURPOSE

To evaluate the clinical and radiological effects of epidural fluid hematoma in the medium term after lumbar endoscopic decompression.

OVERVIEW OF LITERATURE

There is limited literature comparing the effect of postoperative epidural fluid hematoma after uniportal endoscopic decompression.

METHODS

Magnetic resonance imaging (MRI) and clinical evaluation were performed for patients with single-level uniportal endoscopic lumbar decompression with a minimum follow-up of 2 years.

RESULTS

A total of 126 patients were recruited with a minimum follow-up of 26 months. The incidence of epidural fluid hematoma was 27%. Postoperative MRI revealed a significant improvement in the postoperative dura sac area at postoperative day 1 and at the upper endplate at 6 months in the hematoma cohort (39.69±15.72 and 26.89±16.58 mm2) as compared with the nonhematoma cohort (48.92±21.36 and 35.1±20.44 mm2), respectively (p <0.05); and at the lower endplate on postoperative 1 day in the hematoma cohort (51.18±24.69 mm2) compared to the nonhematoma cohort (63.91±27.92 mm2) (p <0.05). No significant difference was observed in the dura sac area at postoperative 1 year in both cohorts. The hematoma cohort had statistically significant higher postoperative 1-week Visual Analog Scale (VAS; 3.32±0.68) pain and Oswestry Disability Index (ODI; 32.65±5.56) scores than the nonhematoma cohort (2.99±0.50 and 30.02±4.84, respectively; p <0.05). No significant difference was found at the final follow-up VAS, ODI, and MRI dura sac area.

CONCLUSIONS

Epidural fluid hematoma is a common early postoperative MRI finding in lumbar endoscopic unilateral laminotomy with bilateral decompression. Conservative management is the preferred treatment option for patients who do not have a neurological deficit. Symptoms last only a few days and are self-limiting. A common endpoint is a remodeled fluid hematoma and the subsequent expansion of the dura sac area.