Learning Curve for Lumbar Decompressive Laminectomy in Biportal Endoscopic Spinal Surgery Using the Cumulative Summation Test for Learning Curve

Prospective comparative analysis of three types of decompressive surgery for lumbar central stenosis: conventional, full-endoscopic, and biportal endoscopic laminectomy

Conventional open laminectomy has long been considered one of the important surgical options for lumbar central stenosis owing to its positive outcomes. However, newer approaches have emerged as alternatives, including full-endoscopic and biportal endoscopic laminectomy. Therefore, a comparison of the outcomes that are associated with each of these surgical methods is warranted. This prospective multicenter trial, initiated in February 2019, compared the outcomes of three lumbar central stenosis surgical approaches: open laminectomy (OPEN), uniportal endoscopy (UNIPORT), and biportal endoscopy (BIPORT). Among 115 participants from seven centers, one-year follow-ups assessed laboratory, radiological, and clinical outcomes. Despite all groups showing adequate decompression and clinical improvement, the OPEN group exhibited less improvement in Visual analog scale (VAS) for back pain scores (p < 0.05) and significant postoperative increases in most laboratory markers. Furthermore, the OPEN group experienced a significant decrease in multifidus muscle cross-sectional area compared to endoscopic groups (p < 0.001). Each surgical techniques produced similar clinical outcomes and dural space expansion. However, endoscopic surgery was associated with better muscle preservation and better relief of back pain. Endoscopic surgery is a reasonable alternative to conventional laminectomy for treating lumbar central stenosis.This trial was registered on CRIS (Clinical Research Information Service, KCT0004355).

The Learning Curve and Clinical Outcomes With 250 Laser Ablations for Brain Tumors: A Pathway to Experience

BACKGROUND AND OBJECTIVES

Laser interstitial thermal therapy (LITT) has gained popularity as a minimally invasive technique for treating brain tumors. Despite its proven safety profile, LITT is not yet widely available, and there is a lack of data on the learning curve required to achieve proficiency. This study analyzes a 250-patient cohort of laser-ablated tumors to describe changes in patient selection and clinical outcomes over time and experience, with the aim of providing insight into the learning curve for incorporating LITT into a neuro-oncology program and identifying a cutoff point that distinguishes novice from expert performance.

METHODS

We retrospectively reviewed 250 patients with brain tumor who underwent LITT between 2013 and 2022. Demographic and clinical data were analyzed. Kaplan Meier curves were used for survival analysis. Operative time was evaluated using exponential curve-fit regression analysis to identify when consistent improvement began.

RESULTS

The patients were divided into quartiles (Q) based on their date of surgery. Mean tumor volume increased over time (Q1 = 5.7 and Q4 = 11.9 cm 3 , P = .004), and newly diagnosed lesions were more frequently ablated ( P = .0001). Mean operative time (Q1 v Q4 = 322.3 v 204.6 min, P < .0001) and neurosurgical readmission rate (Q1 v Q4 = 7.8% v 0%, P = .03) were reduced over time. The exponential curve-fit analysis showed a sustained decay in operative time after case #74. The extent of ablation ( P = .69), the recurrence ( P = .11), and the postoperative complication rate ( P = .78) did not vary over time.

CONCLUSION

After treating 74 patients, a downward trend in the operative time is observed. Patient selection is broadened as experience increases.

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.

Learning Curve of Biportal Endoscopic Spinal Surgery: A Retrospective 2-Center Study

OBJECTIVE

Biportal endoscopic spinal surgery (BESS) technique is a novel, useful, and minimally invasive therapeutic strategy for lumbar degenerative diseases, which has advantages over other surgical techniques. However, the degree of technical difficulty in learning BESS is controversial and not well established. This study aims to determine the learning curve of BESS technique through cumulative sum (CUSUM) analysis.

METHODS

A total of 144 consecutive patients who underwent BESS with lumbar decompressive discectomy between 2017 and 2023 were included. A retrospective bicenter study was performed.

RESULTS

Three doctors with endoscopy experience employed the BESS technique for 51, 42, and 46 procedures, respectively. The CUSUM test of the 3 doctors showed adequate technical ability at the 45th, 41st, and 44th operations respectively. Two doctors without endoscopy experience gave up further use of BESS technique due to technical difficulties after initial attempt. The overall complication rates of the 3 surgeons using the BESS technique were 3.92% (n = 2), 6.82% (n = 3), and 2.17% (n = 1), respectively.

CONCLUSIONS

Our study demonstrated that BESS is an effective treatment, and the learning curves of BESS for lumbar discectomy using CUSUM analysis were 41 ∼ 45 cases in trainees with endoscopic experience. Endoscopic experience contributes to the learning curve of the BESS technique.

Learning curve analyses in spine surgery: a systematic simulation-based critique of methodologies

BACKGROUND CONTEXT

Various statistical approaches exist to delineate learning curves in spine surgery. Techniques range from dividing cases into intervals for metric comparison, to employing regression and cumulative summation (CUSUM) analyses. However, their inherent inconsistencies and methodological flaws limit their comparability and reliability.

PURPOSE

To critically evaluate the methodologies used in existing literature for studying learning curves in spine surgery and to provide recommendations for future research.

STUDY DESIGN

Systematic literature review.

METHODS

A comprehensive literature search was conducted using PubMed, Embase, and Scopus databases, covering articles from January 2010 to September 2023. For inclusion, articles had to evaluate the change in a metric of performance during human spine surgery across time/a case series. Results had to be reported in sufficient detail to allow for evaluation of individual performance rather than group/institutional performance. Articles were excluded if they included cadaveric/nonhuman subjects, aggregated performance data or no way to infer change across a number of cases. Risk of bias was assessed using the Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) tool. Surgical data were simulated using Python 3 and then examined via multiple commonly used analytic approaches including division into consecutive intervals, regression and CUSUM techniques. Results were qualitatively assessed to determine the effectiveness and limitations of each approach in depicting a learning curve.

RESULTS

About 113 studies met inclusion criteria. The majority of the studies were retrospective and evaluated a single-surgeon's experience. Methods varied considerably, with 66 studies using a single proficiency metric and 47 using more than 1. Operating time was the most commonly used metric. Interval division was the simplest and most commonly used method yet inherent limitations prevent collective synthesis. Regression may accurately describe the learning curve but in practice is hampered by sample size and model choice. CUSUM analyses are of widely varying quality with some being fundamentally flawed and widely misinterpreted however, others provide a reliable view of the learning process.

CONCLUSION

There is considerable variation in the quality of existing studies on learning curves in spine surgery. CUSUM analyses, when correctly applied, offer the most reliable estimates. To improve the validity and comparability of future studies, adherence to methodological guidelines is crucial. Multiple or composite performance metrics are necessary for a holistic understanding of the learning process.

Preliminary Clinical and Radiological Outcomes of the "No-Punch" Decompression Techniques for Unilateral Biportal Endoscopic Spine Surgery

OBJECTIVE

To avoid the most offending surgical instrument for dural tears, we develop a "no-punch" decompression technique for unilateral biportal endoscopic (UBE) spine surgery.

METHODS

This retrospective study enrolled 68 consecutive patients with degenerative lumbar spinal stenosis segments. The treatment results were evaluated using the visual analogue scale (VAS) for low back and leg pain, the Japanese Orthopaedic Association (JOA) scores, and the Oswestry Disability Index (ODI). Radiological outcomes were evaluated using the preoperative and postoperative magnetic resonance imaging.

RESULTS

This study included 36 male and 32 female patients who received 109 segments of decompression, with an average age of 68.7 (37-90 years). The average operation time was 52.2 minutes. The average hospital stay was 3.1 days. There were no dural tears but 3 minor surgical complications, all treated conservatively. The VAS for low back and leg pain improved from 4.6 and 7.0 to 0.8 and 1.2. The JOA score improved from 16.2 to 26.8, with an improvement rate of 82.0%. The ODI improved from 50.1 to 18.7. All these improvements were statistically significant. The cross-sectional dural area improved from 61.1 to 151.3 mm2, with an average increase of 90.2 mm2 and 205.3%. 87.1% of the ipsilateral facet joints and 84.7% of the contralateral facet joints were preserved. In 61% of the decompressed segments, the ipsilateral facet joints were preserved better than the contralateral facet joints.

CONCLUSION

The UBE "no-punch" decompression technique effectively avoids the dural tears. It provides effective neural decompression, excellent facet joint preservation, and good treatment outcomes.

Percutaneous endoscopic transforaminal discectomy and unilateral biportal endoscopic discectomy for lumbar disc herniation: a comparative analysis of learning curves

OBJECTIVE

The purpose of this study was to investigate the learning curve of percutaneous endoscopic transforaminal discectomy (PETD) and interlaminar unilateral biportal endoscopic discectomy (UBED) in the treatment of lumbar disc herniation (LDH).

METHODS

Between 2018 and 2023, 120 consecutive patients with lumbar disc herniation (LDH) treated by endoscopic lumbar discectomy were retrospectively included. The PETD group comprised 87 cases, and the UBED group comprised 33 cases. Cumulative sum analysis was used to evaluate the learning curve, with the occurrence of complications or unresolved symptoms defined as surgical failure, and variables of different phases of the learning curve being compared.

RESULTS

The learning curve analysis identified the cutoff point at 40 cases in the PETD group and 15 cases in the UBED group. In the mastery phase, both PETD and UBED demonstrated a significant reduction in operation times (approximately 38 min for PTED and 49 min for UBED). In both PETD and UBED groups, the surgical failure rates during the learning and mastery phases showed no statistically significant differences. The visual analogue scale at the last follow-up was significantly lower than before surgery in both the PETD and UBED groups.

CONCLUSION

PETD and UBED surgery are effective in the treatment of LDH with a low incidence of complications. However, achieving mastery in PETD necessitates a learning curve of 40 cases, while UBED requires a minimum of 15 cases to reach proficiency.

Unilateral biportal endoscopic discectomy versus microdiscectomy for lumbar disc herniation: a systematic review and meta-analysis

PURPOSE

This study aimed to compare unilateral biportal endoscopic discectomy (UBED) with microdiscectomy (MD) for treating lumbar disk herniation (LDH).

METHODS

A comprehensive literature search was conducted in the Embase, PubMed, Cochrane Library, CNKI, and Web of Science databases from database inception to April 2023 to identify studies comparing UBED and MD for treating LDH. This study evaluated the visual analog scale (VAS) score, Oswestry disability index (ODI), Macnab scores, operation time, estimated blood loss, hospital stay, and complications, estimated blood loss, visual analog scale (VAS) score, Oswestry disability index (ODI), and Macnab scores at various pre- and post-surgery stages. The meta-analysis was performed using RevMan 5.4 software.

RESULTS

The meta-analysis included 9 distinct studies with a total of 1001 patients. The VAS scores for low back pain showed no significant differences between the groups at postoperative 1-3 months (P = 0.09) and final follow-up (P = 0.13); however, the UBED group had lower VAS scores at postoperative 1-3 days (P = 0.02). There were no significant differences in leg pain VAS scores at baseline (P = 0.05), postoperative 1-3 days (P = 0.24), postoperative 1-3 months (P = 0.78), or at the final follow-up (P = 0.43). ODI comparisons revealed no significant differences preoperatively (P = 0.83), at postoperative 1 week (P = 0.47), or postoperative 1-3 months (P = 0.13), and the UBED group demonstrated better ODI at the final follow-up (P = 0.03). The UBED group also exhibited a shorter mean operative time (P = 0.03), significantly shorter hospital stay (P < 0.00001), and less estimated blood loss (P = 0.0002). Complications and modified MacNab scores showed no significant differences between the groups (P = 0.56 and P = 0.05, respectively).

CONCLUSION

The evidence revealed no significant differences in efficacy between UBED and MD for LDH treatment. However, UBED may offer potential benefits such as shorter hospital stays, lower estimated blood loss, and comparable complication rates.

Early Clinical and Radiologic Evaluation of Unilateral Biportal Endoscopic Unilateral Laminotomy and Bilateral Decompression in Degenerative Lumbar Spinal Stenosis: A Retrospective Study

BACKGROUND

 The aim of this study is to evaluate the changes in radiologic parameters and clinical outcomes following unilateral biportal endoscopic unilateral laminotomy and bilateral decompression (UBE ULBD) for treatment of central lumbar spinal stenosis.

METHODS

 Forty-one central lumbar spinal stenosis patients who underwent UBE ULBD were enrolled from April 2021 to February 2023. Visual analog scale (VAS) for back pain and leg pain, Oswestry Disability Index (ODI) score, and the modified MacNab criteria were assessed preoperatively and postoperatively. The preoperative and postoperative cross-sectional area of the spinal canal (CSAC), anteroposterior diameter, horizontal width, and ipsilateral and contralateral lateral recess height were calculated from axial computed tomography (CT) scans. Percentage of facet joint preservation measured on axial CT scans was obtained preoperation and postoperation.

RESULTS

 The VAS for back and leg pain improved from 7.24 ± 0.80 and 7.59 ± 0.59 preoperatively to 2.41 ± 0.55 and 2.37 ± 0.62 (p < 0.05) postoperatively and 1.37 ± 0.54 and 1.51 ± 0.55 at the last follow-up (p < 0.05). For ODI, improvement from 60.37 ± 4.44 preoperatively to 18.90 ± 4.66 (p < 0.05) at the last follow-up was observed. CT scans demonstrated that the postoperative CSAC increased significantly from 287.84 ± 87.81 to 232.97 ± 88.42 mm (p < 0.05). The mean postoperative anteroposterior diameter and horizontal width increased significantly from 18.01 ± 3.13 and 19.57 ± 3.80 to 22.19 ± 4.56 and 21.04 ± 3.72 mm, respectively (p < 0.05). The ipsilateral lateral recess height and contralateral lateral recess height were 3.39 ± 1.12 and 3.20 ± 1.14 mm preoperatively and 4.03 ± 1.37 and 3.83 ± 1.32 mm (p < 0.05) postoperatively, with significant differences. The ipsilateral and contralateral facet joint preservations were 88.17 and 93.18%, respectively.

CONCLUSION

 The UBE ULBD surgery is a safe and effective treatment for central lumbar spinal stenosis, associated with significant improvement in clinical outcomes and radiologic parameters. Studies with larger samples and longer follow-up periods are needed for further research.

A Comparison of 2 Cage Sizes in Biportal Endoscopic Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Retrospective study.

OBJECTIVE

This study compared the fusion and subsidence rate and clinical outcomes when using different-sized static PEEK cages in BE-TLIF.

SUMMARY OF BACKGROUND DATA

Biportal endoscopic techniques for transforaminal lumbar interbody fusion (BE-TLIF) have been shown to have similar clinical and fusion outcomes with faster clinical recovery in comparison to tubular surgery. Subsidence of the interbody, however, could be a complication.

METHODS

Patients who underwent 1 or 2 level BE-TLIF for degenerative and isthmic spondylolisthesis between January 2019 and January 2022 were included. A 32×10 mm cage (group A) and a 40×15 mm cage (group B) were compared. The visual analog scale (VAS) for back and leg symptoms, and Oswestry disability index (ODI) were collected. Plain radiographs and computed tomography assessed fusion and subsidence at a minimum of 12 months.

RESULTS

Of the 69 enrolled patients, 39 group A patients (51 levels) and 30 group B patients (32 levels) were compared. The operation time per level was 123 ± 15.8 and 138 ± 10.5 minutes per fusion level in groups A and B, respectively (P < 0.05). ODI improved from 64.8 ± 6.2 to 15.7 ± 7.1 in group A and from 65.3 ± 5.6 to 15.1 ± 6.3 in group B at the final follow-up (P < 0.05). VAS leg and back score improvement between the groups did not differ; however, the 3-month postoperative VAS back improvement was significantly higher in group B. The final fusion rate at the final follow-up did not significantly differ; however, the fusion ratio at 1 year was higher in group B (P < 0.05). Subsidence occurred in 5 cases (9.8%) in group A and none in group B (P < 0.05).

CONCLUSION

BE-TLIF using a larger cage can be performed safely with similar patient-reported outcome measures with a faster fusion rate with less subsidence risk.

LEVEL OF STUDY

III.

Complications in endoscopic spine surgery: a systematic review

PURPOSE

This systematic review aims to investigate the complication rate of endoscopic spine surgeries, stratifying them by technique, district and kind of procedure performed.

METHODS

This study was conducted according to the PRISMA statement. The literature search was conducted in MEDLINE, CINAHL, EMBASE, Cochrane Register, OTseeker and ScienceDirect database. Types of studies included were observational studies (cohort studies, case-control studies and case series) and randomised or quasi-randomised clinical with human subjects. No restrictions on publication year were applied. Repeated articles, reviews, expert's comments, congress abstracts, technical notes and articles not in English were excluded. Several data were extracted from the articles. In particular, data of perioperative (≤ 3 months) and late (> 3 months) complications were collected and grouped according to: (1) surgical technique [uniportal full-endoscopic spine surgery (UESS) or unilateral biportal endoscopic spine surgery (UBESS)]; (2) spinal district treated [cervical, thoracic or lumbar] and (3) type of procedure [discectomy/decompression or fusion]. Complication analysis was performed in subgroups with at least 100 patients to have clinically meaningful statistical validity.

RESULTS

A total of 117 full-text articles were assessed for eligibility. Of the 117 records included, 95 focused their research on UESS (14 LOE V, 33 LOE IV, 43 LOE III and five LOE II) and 23 on UBESS (three LOE V, eight LOE IV, 10 LOE III and two LOE II). A total of 20,020 patients were extracted to investigate the incidence of different perioperative and late complications, 10,405 for UESS and 9615 for UBESS.

CONCLUSION

The present study summarises the complications reported in the literature for spinal endoscopic procedures. On the one hand, the most relevant described were perioperative complications (transient neurological deficit, dural tear and dysesthesia) that are especially meaningful for endoscopic discectomy and decompression. On the other hand, late complications, such as mechanical implant failure, are more common in endoscopic interbody fusion.

LEVEL OF EVIDENCE

I.

Comparing the efficacy of unilateral biportal endoscopic transforaminal lumbar interbody fusion and minimally invasive transforaminal lumbar interbody fusion in lumbar degenerative diseases: a systematic review and meta-analysis

OBJECTIVE

To compare the efficacy and safety of unilateral biportal endoscopic transforaminal lumbar interbody fusion (BE-TLIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in lumbar degenerative diseases.

METHODS

This study was registered on International Prospective Register of Systematic Reviews (PROSPERO) (ID: CRD42023432460). We searched PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wan Fang Database, and Wei Pu Database by computer to collect controlled clinical studies on the efficacy and safety of unilateral BE-TLIF and MIS-TLIF in lumbar degenerative diseases from database establishment to May 2023. Two researchers screened the literature, extracted data and evaluated the risk of bias of the included studies, recorded the authors, and sample size, and extracted the intraoperative blood loss, operation time, postoperative drainage, Oswestry disability index, Visual analogue scale, lumbar lordosis, disk height, hospital length stay, fusion rate, and complications in each study. Meta-analysis was performed using Revman 5.4 software provided by Cochrane Library.

RESULTS

A total of 14 cohort studies with a total of 1007 patients were included in this study, including 472 patients in the BE-TLIF group and 535 patients in the MIS-TLIF group. The BE-TLIF group had lower intraoperative blood loss than the MIS-TLIF group [mean difference (MD) = - 78.72, 95% CI (- 98.47, - 58.97), P < 0.00001] and significantly reduced postoperative drainage than the MIS-TLIF group [MD = - 43.20, 95% CI (- 56.57, - 29.83), P < 0.00001], and the operation time was longer than that of the MIS-TLIF group [MD = 22.68, 95% CI (12.03, 33.33), P < 0.0001]. Hospital length stay in BE-TLIF group was significantly less than that in MIS-TLIF group [MD = - 1.20, 95% CI (- 1.82, - 0.57), P = 0.0002].

CONCLUSION

Compared with MIS-TLIF, BE-TLIF for lumbar degenerative diseases has the advantages of less intraoperative blood loss, less early postoperative low back and leg pain, shorter postoperative hospital length stay, and faster early functional recovery.

Unilateral biportal endoscopic transforaminal lumbar interbody fusion versus conventional interbody fusion for the treatment of degenerative lumbar spine disease: a systematic review and meta-analysis

BACKGROUND

This meta-analysis compares the efficacy of unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) to conventional interbody fusion in lumbar degenerative diseases (LDD).

METHODS

An extensive literature search was conducted in PubMed, Web of Science, and the Cochrane Library. Research related to UBE-TLIF published up to November 2022 was reviewed. The relevant articles were selected based on inclusion and exclusion criteria, as well as an evaluation of the quality of the data extraction literature. Meta-analysis was performed using Review Manager 5.3 software.

RESULTS

This meta-analysis included six high-quality case-control trials (CCTs) involving 621 subjects. The clinical outcomes assessment showed no statistical differences in complication rates, fusion rates, leg pain VAS scores, or ODI scores. After UBE-TLIF, low back pain VAS scores were significantly improved with less intraoperative blood loss and a shorter hospital stay. A longer time was required for UBE-TLIF, however.

CONCLUSION

Despite the lack of sufficient high quality randomized controlled trials (RCTs) in this study, the results of this meta-analysis suggest that UBE-TLIF is more effective than open surgery in terms of length of stay, blood loss reduction during surgery, and improved low back pain after surgery. Nevertheless, the evidence will be supplemented in the future by more and better quality multicenter randomized controlled trials.

Midterm Outcomes of Muscle-Preserving Posterior Lumbar Decompression via Sagittal Splitting of the Spinous Process: Minimum 5-Year Follow-up

Background

To overcome several disadvantages of conventional laminectomy for degenerative lumbar spinal stenosis (DLSS), several types of minimally invasive surgery have been developed. The purpose of the present study was to report the clinical and radiological mid-term outcomes of spinous process-splitting decompression (SPSD) for DLSS.

Methods

Seventy-three consecutive patients underwent SPSD between September 2014 and March 2016. Of these, 42 (70 segments) who had at least 5 years of follow-up were analyzed retrospectively. The visual analog scale for back pain and leg pain, Oswestry disability index, and walking distance without resting were scored to assess clinical outcomes at the preoperative and final follow-up. A subgroup analysis was performed according to the union status of the split spinous processes (SPs). For radiological outcomes, slip in the neutral position as a static parameter, anterior flexion-neutral translation, and posterior extension-neutral translation as a dynamic parameter were measured before and at the final follow-up after surgery. Spinopelvic parameters were also measured. Reoperation rate at the index levels was investigated, and predictive risk factors for reoperation were evaluated using multivariate logistic regression. Survival analysis was performed with reoperation as the endpoint to estimate the longevity of the SPSD for DLSS.

Results

All clinical outcomes improved significantly at the final follow-up compared to those at the initial visit (p < 0.05). The clinical outcomes did not differ according to the union status of the split SP. There were no cases of definite segmental instability and no significant changes in the static or dynamic parameters after surgery. Sacral slope and lumbar lordosis increased, and pelvic tilt decreased significantly at the follow-up (p < 0.05), despite no significant change in the sagittal vertical axis. The mean longevity of the procedure before the reoperation was 82.9 months. Five patients (11.9%) underwent reoperation at a mean of 52.2 months after the SPSD. There were no significant risk factors for reoperation; however, the preoperative severity of foraminal stenosis had an odds ratio of 7.556 (p = 0.064).

Conclusions

SPSD for DLSS showed favorable clinical and radiological outcomes at the mid-term follow-up. SPSD could be a good surgical option for treating DLSS.

Technical Feasibility and Early Clinical Outcome of Biportal Endoscopic Transforaminal Lumbar Interbody Fusion Using Larger Cage

BACKGROUND

Transforaminal lumbar interbody fusion with biportal endoscopic guidance (BE-TLIF) has been previously reported with promising clinical results. However, complications such as delayed union or subsidence occurred as with open surgery. We assumed using larger cages would result in less occurrence of such complications. We aimed to analyze the clinical outcome and technical feasibility of BE-TLIF using larger cages, initially designed for oblique lumbar interbody fusion.

METHODS

We enrolled cases that underwent single-level BE-TLIF between January 2021 and January 2022. Polyetheretherketone cages that were larger than the conventional size were used. Diagnoses were degenerative spondylolisthesis or isthmic spondylolisthesis. Visual analog scale scores of the back and leg and Oswestry Disability Index were collected perioperatively. Modified Macnab criteria were used to evaluate the patients at the final follow-up. Radiologic outcome of interbody fusion rate and perioperative complications were analyzed.

RESULTS

A total of 35 cases were included in this study. The mean age was 67.5 ± 8.4 and consisted of 13 male patients, and the mean follow-up duration was 18.3 ± 3.7 months. The majority (32/35, 91.3%) of the index level was located within the lower lumbar region, L4-S1. Oswestry Disability Index scores improved from 65.4 ± 5.4 preoperatively to 15.4 ± 6.1 at the final follow-up (P < 0.001). Visual analog scale scores of the leg decreased from 7.9 ± 1.5 to 1.7 ± 1.5 at the final follow-up (P < 0.001). Per the modified Macnab criteria on the final follow-up, 94% of the patients reported good/excellent. Most (94.2%) of the patients showed fusion grade I and II at the 1-year follow-up. No patient showed subsidence or other postoperative complication.

CONCLUSIONS

BE-TLIF using a larger cage was safely performed without risk of subsidence during the 1-year follow-up. A cage with a larger footprint may be advantageous in BE-TLIF in the aspect of interbody fusion and subsidence.

A Beginner's Perspective on Biportal Endoscopic Spine Surgery in Single-Level Lumbar Decompression: A Comparative Study with a Microscopic Surgery

Background

The application of biportal endoscopic spinal surgery (BESS) in spine surgery is increasing. However, the clinical results of related studies have been inconsistent. In this study, the perioperative and clinical outcomes of two techniques in single-level lumbar decompression surgery were compared using the perspective of a spine surgeon experienced in microscopic surgery but inexperienced in BESS.

Methods

This is a retrospective study performed with prospectively collected data. From April 2019, 50 consecutive patients who underwent a single-level lumbar decompression surgery with BESS were evaluated. Additionally, the data of 150 consecutive patients who underwent the same microscopic surgery before April 2019 were collected. We performed 1 : 1 ratio propensity score matching for these two groups to adjust for baseline variables. The postoperative patient-reported outcome measures included the Oswestry Disability Index (ODI) and numeric rating scale for the back and leg preoperatively and at 6 months after surgery. The laboratory data (C-reactive protein [CRP, mg/L] and hemoglobin [Hb, g/dL]) were measured preoperatively and 3 times (1, 2, and 3 or 4 days) postoperatively. In these periods, the peak and lowest CRP and Hb concentrations were evaluated. The perioperative outcomes, operation time (from skin incision to dressing), length of hospital stay, drainage (for 24 hours after surgery), and surgery-related complications were also evaluated.

Results

Forty-seven patients (27 men and 20 women) were included in each group. The postoperative 6-month ODI was significantly lower in the BESS group than in the microscope group (6.90 ± 5.98 vs. 11.54 ± 9.70). The peak CRP concentration (16.63 ± 19.41 vs. 42.40 ± 37.73, p < 0.001) and CRP increment (peak CRP minus preoperative CRP, 14.69 ± 19.47 vs. 40.71 ± 37.32, p < 0.001) were significantly higher in the microscope group. Operation time (83.72 ± 35.71 vs. 70.27 ± 23.24, p = 0.047) was significantly longer in the BESS group. Surgery-related complications were found in 6 and 3 cases in the BESS group (3 revisions, 2 dural tears, and 1 conversion to open surgery) and microscope group (2 revisions and 1 hematoma), respectively.

Conclusions

BESS as a new technique resulted in satisfying short-term outcomes. It was a well-tolerated option for surgical treatment of single-level lumbar degenerative disease. The relatively high incidence of recurrence at the index level and incidental dural tears should be considered for surgeons new to BESS; however, these were manageable complications.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Pin-assisted retraction technique in unilateral biportal endoscopic discectomy: a retrospective cohort study

OBJECTIVE

Unilateral biportal endoscopic (UBE) discectomy is a reliable endoscopic technique in the treatment of lumbar disc herniation. However, UBE discectomy involves a single-handed manipulation, which may compromise the utility of the procedure. The present study was performed to examine the efficacy and safety of a novel pin-assisted retraction technique.

METHODS

This single-center retrospective cohort study involved 57 consecutive patients who underwent UBE lumbar discectomy from July 2021 to May 2022. The patients were randomly divided into the pin-assisted UBE discectomy group (P-UBE group) and the traditional UBE discectomy group (T-UBE group). The patients' perioperative data, clinical outcomes, and radiologic outcomes were collected and compared between the two groups.

RESULTS

The operative time, intraoperative blood loss, endoscopic irrigation volume, and overall complication rate were significantly lower in the P-UBE group than in the T-UBE group. There were no significant differences in the clinical outcome data between the two groups.

CONCLUSION

P-UBE discectomy may have superior safety and efficacy over the traditional technique, and it has the potential to serve as an optional method in UBE lumbar surgery.

Clinical outcomes and complications after biportal endoscopic spine surgery: a comprehensive systematic review and meta-analysis of 3673 cases

PURPOSE

Current literature suggests that biportal spinal endoscopy is safe and effective in treating lumbar spine pathology such as lumbar disc herniation, lumbar stenosis, and degenerative spondylolisthesis. No prior study has investigated the postoperative outcomes or complication profile of the technique as a whole. This study serves as the first comprehensive systematic review and meta-analysis of biportal spinal endoscopy in the lumbar spine.

METHODS

A PubMed literature search provided over 100 studies. 42 papers were reviewed and 3673 cases were identified with average follow-up time of 12.5 months. Preoperative diagnoses consisted of acute disc herniation (1098), lumbar stenosis (2432), and degenerative spondylolisthesis (229). Demographics, operative details, complications, and perioperative outcome and satisfaction scores were analyzed.

RESULTS

Average age was 61.32 years, 48% male. 2402 decompressions, 1056 discectomies, and 261 transforaminal lumbar Interbody fusions (TLIFs) were performed. Surgery was performed on 4376 lumbar levels, with L4-5 being most common(61.3%). 290 total complications occurred, 2.23% durotomies, 1.29% inadequate decompressions, 3.79% epidural hematomas, and < 1% transient nerve root injuries, infections, and iatrogenic instability. Significant improvement in VAS-Back, VAS-Leg, ODI, and Macnab Scores were seen across the cohort.

CONCLUSION

Biportal spinal endoscopy is a novel method to address pathology in the lumbar spine with direct visualization through an endoscopic approach. Complications are comparable to previously published rates. Clinical outcomes demonstrate effectiveness. Prospective studies are required to assess the efficacy of the technique as compared to traditional techniques. This study demonstrates that the technique can be successful in the lumbar spine.

Biportal endoscopic surgery for lumbar spine herniated discs: a narrative review of its clinical application and outcomes

Lumbar disk herniation (LDH) is a common condition affecting millions worldwide. The management of LDH has evolved over the years, with the development of newer surgical techniques that aim to provide better outcomes with minimal invasiveness. One promising emerging technique is biportal endoscopic spinal surgery (BESS), which utilizes specialized endoscopic equipment to treat LDH through two small incisions. This review aims to assess the effectiveness of BESS as a management option for LDH by analyzing the available literature on surgical outcomes and potential complications associated with the technique. Our review shows that BESS is associated with favorable postoperative results as judged by clinical scoring systems, such as visual analog scale, Oswestry disability index, and MacNab criteria. BESS has several advantages over traditional open surgery, including minimized blood loss, a shorter duration of hospitalization, and an expedited healing process. However, the technique has limitations, such as a steep learning curve and practical challenges for surgeons. Our review offers recommendations for the optimal use of BESS in clinical practice, and provides a foundation for future research and development in this field, aiming to improve patient outcomes and quality of life.

Uniportal versus biportal endoscopic spine surgery: a comprehensive review

INTRODUCTION

Endoscopic spine surgery techniques are minimally invasive alternatives to conventional open surgery for degenerative spinal diseases. Clinical studies and meta-analyses have proven the usefulness of uniportal full-endoscopic spine procedures. However, a steep learning curve is a critical barrier for endoscopic procedures. Recently, biportal endoscopic spine surgeries have been developed to make it easier for spine surgeons to learn and perform. Consequently, the biportal approach has gained popularity among aspiring endoscopic spine surgeons. This review compared the characteristics of uniportal and biportal surgeries to help spine surgeons perform endoscopic procedures more effectively.

AREA COVERED

The review analyzed English-language clinical literature in Core databases and compared uniportal and biportal endoscopic spine surgery techniques. Clinical studies have compared the technical principles of both techniques, and the authors suggested appropriate strategies for learning and practicing endoscopic procedures.

EXPERT OPINION

Uniportal, full-endoscopic spine surgery is a minimally invasive procedure that preserves muscles and uses a keyhole approach under local anesthesia. In contrast, biportal surgery is more familiar to a surgeon and can be performed more widely, although the keyhole approach is limited. Aspiring endoscopic spine surgeons can learn either method according to the surgeon's preference and the clinical situation.

Clinical Efficacy of Bilateral Decompression Using Biportal Endoscopic Versus Minimally Invasive Transforaminal Lumbar Interbody Fusion for the Treatment of Lumbar Degenerative Diseases

OBJECTIVE

The study purpose was to compare unilateral biportal endoscopic lumbar interbody fusion (ULIF) with minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for the treatment of lumbar degenerative diseases in terms of surgical trauma and short-to medium-term postoperative results.

METHODS

Forty-nine patients with lumbar degenerative diseases (25 underwent ULIF, 24 underwent MIS-TLIF) who were treated between May 2019 and October 2021, were included in this retrospective analysis. We compared the 2 groups' blood loss, serum C-reactive protein (CRP), visual analog scale (VAS) scores for low back and leg pain, and the Oswestry Disability Index (ODI) score and slip percentage (SP). The modified Macnab score was obtained at the last follow-up.

RESULTS

On the postoperative day, the CRP levels (P < 0.05) were considerably lower in the ULIF group than those in the MIS-TLIF group. In addition, the ULIF group had significantly decreased intraoperative blood loss (P = 0.00) and postoperative blood loss (P = 0.00). After surgery, there was significant improvement in both groups in the VAS scores for low back and leg pain and in the ODI scores (P < 0.05). Two weeks after surgery, the ODI and VAS scores for low back pain of the ULIF group were considerably lower than those of the MIS-TLIF group (P < 0.05). The excellent and good rates of the Macnab criteria between the 2 groups were not significantly different at the last follow-up (P = 0.95).

CONCLUSIONS

The ULIF technique can effectively treat short-segment lumbar degenerative diseases and is a feasible alternative to the traditional minimally invasive surgery.

Learning curve for biportal endoscopic posterior cervical foraminotomy determined using the cumulative summation test

BACKGROUND

Learning curves describe the rate of performance improvements corresponding to the surgeon's caseload, followed by a plateau where limited further improvements are observed. This study aimed to determine the learning curve for biportal full-endoscopic posterior cervical foraminotomy (BE-PCF) for the unilateral cervical foraminal disc.

METHODS

The learning curve was evaluated using a learning curve cumulative summation test (LC-CUSUM). The goal for the operation time was set to 78 min, which is the mean operation time (mOT) of percutaneous full-endoscopic posterior cervical foraminotomy (PE-PCF) performed by a senior surgeon. Moreover, clinical outcomes and post-operative complications were compared between the early and late learning periods 1 year post-operatively.

RESULTS

This study enrolled the first 50 patients who underwent single-level BE-PCF, performed by a single surgeon. The LC-CUSUM signalled competency for surgery at the 20th operation, indicating that sufficient evidence was obtained to prove that the surgeon was competent. The mOT was 71.29 ± 11.69 min in BE-PCF, 71.84 ± 12.61 min in the early learning period, and 67.83 ± 10.31 min in the late learning period (p = 0.254). There was no statistical difference in clinical outcomes, visual analogue scale scores, and neck disability index between both periods (p > 0.05). Four complications were recorded throughout the whole period, with three in the early period and one in the late period (p = 0.285).

CONCLUSION

Our study shows that BE-PCF has a learning curve of 20 caseloads to achieve 90% proficiency, and it significantly reduces the operation time based on the performance of a senior surgeon proficient in PE-PCF.

Complications of Unilateral Biportal Endoscopic Spinal Surgery for Lumbar Spinal Stenosis: A Meta-Analysis and Systematic Review

BACKGROUND

In recent years, unilateral biportal endoscopic spinal surgery has been used for the treatment of lumbar spinal stenosis with good results. Some investigators counted the total incidence of complications in unilateral biportal endoscopic surgery for lumbar spinal stenosis, but none have analyzed the incidence of specific complications. The present study further counted the incidence of specific complications and gave the possible causes of the complications.

METHODS

English databases including PubMed were searched to collect relevant literature on unilateral biportal endoscopic spinal surgery for lumbar spinal stenosis. The inquiry period is from January 1, 2015, to July 1, 2022. The literature was screened, information extracted, and risk of bias evaluated by the researchers, followed by Meta analysis using R4.2.1 and RStudio statistical software.

RESULTS

In total, we included 14 studies involving 707 patients. The included studies were retrospective case series, The results of the single-arm rate meta-analysis showed that the total complication rate of unilateral biportal endoscopic surgery treatment of lumbar spinal stenosis was 8.1% (95% confidence interval [CI] [0.060; 0.103]); of which, the highest incidence of dural tear was 4.5% (95% CI [0.030; 0.064]), the incidence of symptomatic postoperative spinal epidural hematoma was approximately 1.1% (95% CI [0.001; 0.027]), the incidence of incomplete decompression was 2.0% (95% CI [0.007; 0.038]), the incidence of transient palsy was 2.6% (95% CI [0.005; 0.057]).

CONCLUSIONS

The incidence of total complications of unilateral biportal endoscopic surgery for lumbar spinal stenosis was 8.1%, dural tear remained a major complication with an incidence of 4.5%, incomplete decompression was 2.0%, transient palsy was 2.6%, and, unexpectedly, symptomatic postoperative spinal epidural hematoma was only 1.1%.

Delta large-channel technique versus microscopy-assisted laminar fenestration decompression for lumbar spinal stenosis: a one-year prospective cohort study

PURPOSE

When it comes to treating lumbar spinal stenosis (LSS), a procedure known as microscope-assisted fenestration decompression has expediently become the gold standard. With the advancement of spinal endoscopy, the Delta large-channel approach has shown promising clinical outcomes in the management of lumbar spinal stenosis. However, case studies of this method being used to treat lumbar spinal stenosis are still uncommon. The purpose of this research was to examine how well microscopy-assisted laminectomy and the Delta large-channel approach work in treating LSS in the clinic.

METHODS

From May 2018 to June 2020, 149 patients diagnosed with LSS were divided into 80 patients in Delta large-channel technique groups (FE group) and 69 patients in microscope groups (Micro group). Lower back and lower limb pain were measured using the visual analogue scale (VAS-LBP and VAS-LP), while lower limb numbness was evaluated using the 11-point numerical rating scale (NRS-LN); modified Oswestry Disability Index (ODI) was used to evaluate the quality of life, and modified MacNab criteria were used to assess the clinical efficacy before surgery and at one week, three months, six months, and 12 months after surgery. All patients had single-level lumbar spinal stenosis, and clinical data such as hospital stay, operation time, intraoperative blood loss were statistically analyzed.

RESULTS

Finally, 111 patients (62 in FE group and 49 in Micro group) completed follow-up. Compared with preoperative results, postoperative VAS-LBP, VAS-LP, NRS-LN score and modified ODI score were significantly improved in 2 groups (P < 0.05), but there was no significant difference in postoperative follow-up at each time point (P > 0.05), Except 1 week after surgery, VAS-LBP in FE group was lower than that in Micro group (P < 0.05). It is noteworthy that the FE group had a shorter hospital stay, less intraoperative blood loss, and a quicker time of getting out of bed when compared with the microscope group，but the operation time was just the opposite (P < 0.05). The excellent and good rate was 83.87% in FE group and 85.71% in Micro group (P > 0.05).

CONCLUSIONS

Both microscope-assisted laminar fenestration decompression and Delta large-channel procedures provide satisfactory treatment outcomes, however the Delta large-channel approach has some potential advantages for the treatment of LSS, including quicker recovery and sooner reduced VAS-LBP. Long-term consequences, however, will necessitate additional follow-up and research.

Biportal endoscopic versus microscopic discectomy for lumbar herniated disc: a randomized controlled trial

BACKGROUND CONTEXT

Biportal endoscopic discectomy has been frequently performed in recent years and has shown acceptable clinical outcomes. However, evidence regarding its efficacy and safety remains limited.

PURPOSE

This study aimed to compare the clinical efficacy and safety of biportal endoscopic with that of open microscopic discectomy in patients with single-level herniated lumbar discs.

STUDY DESIGN

Prospective, randomized, multicenter, open-label, assessor-blind, non-inferiority controlled trial.

PATIENT SAMPLE

Sixty-four participants suffering from low back and leg pain with a single-level herniated lumbar disc and required discectomy.

OUTCOME MEASURES

Outcomes were assessed with the use of patient-reported outcome measures (PROMs), visual analog scale (VAS) pain score for surgical site, low back and lower extremity, Oswestry Disability Index (ODI) for lumbar disabilities, European Quality of Life-5 Dimensions value for quality of life, and painDETECT for neuropathic pain. Surgery-related outcomes such as hospital stay, operation time, and opioid usage were collected. Adverse events occurring during the follow-up period were also noted.

METHODS

All participants were randomly assigned in a 1:1 ratio to undergo biportal endoscopic (biportal group) or microscopic discectomy (microscopy group). The primary outcome was the difference in ODI scores at 12-months post surgically based on a modified intention-to-treat strategy, with a non-inferiority margin of 12.8 points. The secondary outcomes included PROMs, surgery-related outcomes, and adverse events.

RESULTS

The ODI score at the 12-month follow-up was 11.97 in the microscopy group and 13.89 in the biportal group (mean difference, 1.92; 95% confidence interval [CI], -3.50 to 7.34), showing the non-inferiority of biportal group. The results for the secondary outcomes were similar to those for the primary outcome. Creatinine phosphokinase ratios were low in the biportal group. Early surgical site pain was slightly lower in the biportal group (mean difference of VAS pain score at 48-hr, -0.98; 95% CI, -1.77 to -0.19). Adverse events including reoperation showed no significant difference between the groups.

CONCLUSION

Biportal endoscopic discectomy was non-inferior to microscopic discectomy over a 12 month period. Biportal endoscopic discectomy is suggested to be a relatively safe and effective surgical technique with the slight advantage of reduced muscle damage. However, the clinical implications of surgical site pain should be carefully considered.

Training to be a spinal endoscopic surgeon: What matters?

Objective

Spinal endoscopic surgery has been promoted rapidly in the past decade, attracting an increasing number of young, dedicated surgeons. However, it has long been denounced for its long learning curve as a factor impeding the development of this state-of-the-art technique. The aim of the present study was to discover what really matters in the educational process of becoming a spinal endoscopic surgeon.

Methods

An online survey consisting of 14 compulsory questions was distributed in April and May 2022 through the First Chinese Spinal Endoscopic Surgeons Skills Competition. Reminders were sent to increase response rates.

Results

Of the 893 emails that were sent, we received 637 responses. A total of 375 (76.7%) surgeons most frequently used endoscopic techniques in their practices. Regardless of their different backgrounds, 284 (75.7%) surgeons thought it would be necessary for a young spinal endoscopic surgeon to perform 300 cases independently in order to become proficient, followed by 500 (n=43, 11.5%), 100 (n=40, 10.7%), and 1,000 (n=8, 2.1%) cases. According to the surgeons, the most difficult aspect of mastering the endoscopic technique is a disparate surgical view (n=255, 68%), followed by adaption to new instruments (n=86, 22.9%) and hand-eye coordination (n=34, 9.1%). The most helpful training method for helping the spinal endoscopic surgeons of younger generations improve is operating on simulation models or cadaver courses (n=216, 57.6%), followed by online or offline theoretical courses (n=67, 17.9%), acquiring opportunities during surgeries (n=51, 13.6%), and frequently participating in surgeries as an assistant (n=41, 10.9%).

Conclusion

From the perspective of surgeons, to be skilled in spinal endoscopic surgery means overcoming a steep learning curve. However, training systems should be given more attention to make them more accessible to younger surgeons so they can work on simulation models or take cadaver courses.

Recent Updates on Minimally Invasive Spine Surgery: Techniques, Technologies, and Indications

A number of minimally invasive spine surgeries (MISSs) have been developed to address the drawbacks of open spine surgery. Their advantages include small skin incisions, reduction in tissue damage, quick recovery, and short hospital stay. However, the clinical outcomes are comparable to open surgery. There was a cap on the number of indications that could be set for all spinal illnesses. The indications for MISSs have been expanding owing to mechanical and technological advances in medical equipment. Thus, this review presents the various MISSs developed to date, surgical indications, surgical techniques, and their advantages and disadvantages.

Complications of Unilateral Biportal Endoscopic Spinal Surgery for Lumbar Spinal Stenosis: A Systematic Review of the Literature and Meta-analysis of Single-arm Studies

PURPOSE

This article aims to summarize the incidence of these complications through a meta-analysis, analyze the causes of complications and provide clinical promotion and recommendations.

METHODS

Databases and retrieval platform including PubMed, Web of science, Springer link, Cochrane clinical trials, ProQuest, ScienceDirect, Europe PMC, Wiley online, OVID, Clinical trials, CNKI and WanFang, and supplement the literature through Google Scholar, collect all the unilateral biportal endoscopy (UBE) controlled trials and non-controlled trials of UBE in the treatment of lumbar spinal stenosis (LSS). The search time limit is from January 1, 2000 to December 25, 2021. After two reviewers independently screened the literature, extracted data and evaluated the risk of bias in the included studies, meta-analysis was performed using Stata 15.1 software.

RESULTS

Finally, 24 studies were included, including 999 patients. The results of a single-arm rate meta-analysis showed that the overall complication rate of UBE treatment of LSS was 6.27% [95% CI (0.0412, 0.0876)], and the incidence of dural tear was 2.49% [95% CI (0.0133, 0.0390)], the incidence of transient paresthesia was 0.14% [95% CI (0.0000, 0.0072)], the incidence of postoperative spinal epidural hematoma was 0.27% [95% CI (0.0000, 0.0096)], the incidence of postop headache, inadequate decompression, root injury and infection was 0.00%.

CONCLUSION

Current evidence shows that the complication rate of UBE in the treatment of LSS is low, mainly due to dural tears. Limited by the number and quality of included studies, the above conclusions still need to be confirmed by more studies.

Results of single-incision distal biceps tendon repair for early-career upper-extremity surgeons

Background

The purpose of this investigation was to assess surgical outcomes after distal biceps tendon (DBT) repair for upper-extremity surgeons at the beginning of their careers, immediately following fellowship training. We aimed to determine if procedure times, complication rates, and clinical outcomes differed during the learning curve period for these early-career surgeons.

Methods

All cases of DBT repairs performed by 2 fellowship-trained surgeons from the start of their careers were included. Demographic data as well as operative times, complication rates, and patient reported outcomes were retrospectively collected. A cumulative sum chart (CUSUM) analysis was performed for the learning curve for both operative times and complication rate. This analysis continuously compares performance of an outcome to a predefined target level.

Results

A total of 78 DBT repairs performed by the two surgeons were included. In the CUSUM analysis of operative time for surgeon 1 and 2, both demonstrated a learning curve until case 4. In CUSUM analysis for complication rates, neither surgeon 1 nor surgeon 2 performed significantly worse than the target value and learning curve ranged from 14 to 21 cases. Mean Disabilities of Arm, Shoulder, and Hand score (QuickDASH) (10.65 ± 5.81) and the pain visual analog scale scores (1.13 ± 2.04) were comparable to previously reported literature.

Conclusions

These data suggest that a learning curve between 4 and 20 cases exists with respect to operative times and complication rates for DBT repairs for fellowship-trained upper-extremity surgeons at the start of clinical practice. Early-career surgeons appear to have acceptable clinical results and complications relative to previously published series irrespective of their learning stage.

Learning curve for microscopic unilateral laminectomy for bilateral decompression surgery using the cumulative summation test for learning curve

A retrospective observational study The purpose of this study was to characterize the learning curve for a single level unilateral laminectomy and bilateral decompression in lumbar spinal stenosis using a learning curve cumulative summation test. Unilateral laminectomy and bilateral decompression for lumbar spinal stenosis proposes a potential benefit with minimizing surgery-related instability compared to traditional bilateral laminectomy, by preserving posterior stabilizing structures and contralateral facet joint and neural arch. Due to a narrow surgical corridor, it is considered to exhibit a steep learning curve as other types of minimally invasive procedures. However, there are few reports available regarding learning curve of unilateral laminectomy and bilateral decompression. The learning curve of a single surgeon performing single level unilateral laminectomy and bilateral decompression was assessed using learning curve cumulative summation test analysis. The surgeon had minimal experience in open decompressive laminectomy but no previous experience in unilateral laminectomy and bilateral decompression. Procedure success was defined as an operation time less than 75 minutes. Surgery related complications were recorded. Total 194 consecutive patients, who underwent primary single level unilateral laminectomy and bilateral decompression by a single spine surgeon, were included. The mean operative time for unilateral laminectomy and bilateral decompression was 64.6 ± 23.6 minutes. The mean operative time in the early learning period (≤29th case) was 80.6 ± 20.9 minutes, and that in the late learning period (after 29th case) was 61.8 ± 22.7 minutes, respectively. The overall complication rate was 13.9%. Majority of complications occurred in the early learning period. The learning curve cumulative summation test signaled competency for unilateral laminectomy and bilateral decompression at the 29th operation, indicating that the surgeon reached the competent level. In addition, based on the cumulative summation test, the surgeon seemed to maintain his competency for the procedure. This study showed that surgical experience reduced the operation time and surgery related complications. For inexperienced surgeon to achieve an acceptable outcome in unilateral laminectomy and bilateral decompression, minimum 30 cases of unilateral laminectomy and bilateral decompression are required to reach competent level of surgery.

[Research of learning curves for unilateral biportal endoscopy technique and associated postoperative adverse events]

OBJECTIVE

To summarize the characteristics of the learning curve and the occurrence of postoperative adverse events during the development of unilateral biportal endoscopy (UBE) technique by comparing the clinical data of early and late patients treated with UBE technique.

METHODS

All patients who underwent single-level UBE technique between April 1, 2020 and December 31, 2021 were selected as the research subjects. According to the surgical options, all patients were allocated into 3 groups: unilateral decompression and discectomy (UDD) group, unilateral laminotomy for bilateral decompression (ULBD) group, and lumbar intervertebral fusion (LIF) group. The first 60 cases from each group were extracted and ranked orderly. The endoscopic operation time, the times of fluoroscopy during non-internal fixation implantation, the postoperative hospital stay, the drainage volume, the decrease of hemoglobin, the decrease of hematocrit, and the adverse events were collected. In each group, the patients were allocated into early and late cases according to the operation sequence. The first 30 cases of each group were classified as early cases, and the last 30 cases as late cases. Statistical analysis was performed on the above observation indicators between the early and late cases, and a scatter plot of relevant data changes was drawn to observe the change trend.

RESULTS

Compared with the early cases, the endoscopic operation time and the times of fluoroscopy during non-internal fixation implantation of late cases in each group were significantly lower ( P<0.05); the postoperative hospital stay of late cases in LIF group was significantly shorter ( P<0.05); the decreased values of hemoglobin and hematokrit of late cases in ULBD group and LIF group were significantly lower ( P<0.05); the postoperative drainage volume of late cases in ULBD group significantly decreased ( P<0.05). The endoscopic operation time and the times of fluoroscopy during non-internal fixation implantation of 3 groups showed a significant downward trend. The adverse events occurred in 3 early cases and 1 late case of the UDD group, in 6 and 3 cases of the UBLD group, and 8 and 3 cases of the LIF group, respectively. The difference was not significant between the early and late cases ( P>0.05).

CONCLUSION

In the early practice of UBE technique, there is a high incidence of complication, and the surgical trauma is relatively large, which is related to the lack of understanding of the UBE technique characteristics and insufficient surgical experience. With the proficiency of surgical techniques and accumulation of experience, the operation time and the incidence of postoperative adverse events were significantly reduced.

Efficacy and safety of unilateral biportal endoscopy versus other spine surgery: A systematic review and meta-analysis

Background

This study aimed to evaluate the efficacy and safety of unilateral biportal endoscopy (UBE) versus other forms of spine surgery.

Methods

Electronic databases were systematically searched up to February 2022. The authors used Review Manager 5.3 to manage the data and perform the review.

Results

After the preliminary selection of 239 studies from electronic databases, the full inclusion criteria were applied; 16 studies were found to be eligible for inclusion. These 16 studies enrolled 1,488 patients: 653 patients in the UBE group, 570 in the microendoscopic discectomy group, 153 in the percutaneous endoscopic lumbar discectomy group, and 70 in the posterior lumbar interbody fusion group. UBE was superior to microendoscopic discectomy regarding 1-day Visual Analog Scale(VAS) back pain scores (P < 0.00001). No difference was found between UBE and microendoscopic discectomy regarding 1-day Visual Analog Scale leg pain scores (P = 0.25), long-term VAS back pain scores (P = 0.06), long-term VAS leg pain scores (P = 0.05), Oswestry Disability Index scores (P = 0.09) or complications (P = 0.19). Pooled analysis indicated that UBE was similar to percutaneous endoscopic lumbar discectomy regarding 1-day VAS back pain scores (P = 0.71), 1-day VAS leg pain scores (P = 0.37), long-term VAS back pain scores (P = 0.75), long-term VAS leg pain scores (P = 0.41), Oswestry Disability Index scores (P = 0.07) and complications (P = 0.88). One study reported no difference between UBE and posterior lumbar interbody fusion regarding long-term VAS back pain, long-term VAS leg pain, or Oswestry Disability Index scores.

Conclusions

UBE is superior to microendoscopic discectomy to relieve back pain 1 day postoperatively. However, these two procedures are similar regarding 1-day leg pain relief, long-term effects, and safety. UBE and percutaneous endoscopic lumbar discectomy are similar regarding 1-day pain relief, long-term effects and safety. More evidence is needed to evaluate the efficacy and safety of UBE versus posterior lumbar interbody fusion.

Biportal endoscopic spine surgery for cervical disk herniation: A technical notes and preliminary report

Biportal endoscopic spine surgery (BESS) for cervical disk herniation (CDH) has been rarely reported. The aim of the article is to describe a novel BESS as a posterior approach for CDH and report the preliminary outcomes and complications. This single-centered retrospective chart review included 109 consecutive patients who underwent BESS for symptomatic single-level CDH. Working and viewing portals were created in each unilateral paravertebral area at the target disk level. Endoscopic exploration allowed for effective and minimally invasive decompression via safe access to the medial foramen with minimal laminectomy and facetectomy. Clinical outcomes, including the visual analog scale, neck disability index, Macnab criteria, and the motor function of the involved arm, were evaluated at 4, 8, 12, and 24 postoperative weeks. Visual analog scale and neck disability index improved significantly at 24 weeks postoperatively (P < .01). According to the Macnab criteria, "excellent," "good," and "fair" results were obtained for 55.9%, 30.3%, and 13.8% of patients, respectively. The post 24-week distribution of the involved upper extremity strength grade was significantly improved compared to the initial value (P = .02). One patient had a motor weakness with a decreased grade over 4 weeks from excessive irrigation. The posterior approach of BESS was efficient and feasible for the treatment of CDH.

Cost Analysis With Use of Expandable Cage or Cement in Single level Thoracic Vertebrectomy in Metastasis

STUDY DESIGN

Retrospective case series.

OBJECTIVE

Patient with metastatic cancer frequently require spinal operations for neural decompression and stabilization, most commonly thoracic vertebrectomy with reconstruction. Objective of the study was to assess economic aspects associated with use of cement versus expandable cage in patients with single level thoracic metastatic disease. We also looked at the differences in the clinical, radiological, complications and survival differences to assess non-inferiority of PMMA over cages.

METHODS

The electronic medical records of patients undergoing single level thoracic vertebrectomy and reconstruction were reviewed. Two groups were made: PMMA and EC. Totals surgical cost, implant costs was analyzed. We also looked at the clinical/ radiological outcome, complication and survival analysis.

RESULTS

96 patients were identified including 70 one-level resections. For 1-level surgeries, Implant costs for use of cement-$75 compared to $9000 for cages. Overall surgical cost was significantly less for PMMA compared to use of EC. No difference was seen in clinical outcome or complication was seen. We noticed significantly better kyphosis correction in the PMMA group.

CONCLUSIONS

Polymethylmethacrylate cement offers significant cost advantage for reconstruction after thoracic vertebrectomy. It also allows for better kyphosis correction and comparable clinical outcomes and non-inferior to cages.

Anterior controllable antedisplacement and fusion: quantitative analysis of a single surgeon's learning experience

BACKGROUND CONTEXT

Anterior controllable antedisplacement and fusion (ACAF) is a novel surgical technique for the treatment of ossification of the posterior longitudinal ligament (OPLL) but the surgical learning curve for this technique has not been previously characterized.

PURPOSE

The aim of this study was to quantify a surgeon's learning curve for ACAF and the effect of surgeon experience on postoperative outcomes.

STUDY DESIGN

Prospective study of a single institution and single surgeon experience with ACAF surgery.

PATIENT SAMPLE

A total of 70 consecutive patients with OPLL undergoing ACAF surgery by a single, non-ACAF trained surgeon between 2017 and 2020 were analyzed.

OUTCOME MEASURES

Intraoperative and postoperative outcomes (blood loss, operative time, errors of surgical procedure, length of hospital stay, Japanese Orthopedic Association (JOA) scoring system, and surgical complications) were assessed.

METHODS

We prospectively reviewed the first 70 ACAF procedures between 2017 and 2020 performed by a single, non-ACAF trained surgeon. The function relationship between the operative time and case number was fitted using a locally weighted scatterplot smoothing (LOESS) plot. Spearman's correlation analysis was performed to determine factors affecting the operative time. The operative time-related learning curve for ACAF was established and difficulty of each procedure was assessed using a cumulative sum (CUSUM) model. The association between the specific errors of surgical procedures and surgeon experience was further analyzed. A modified CUSUM model was also used to establish the surgical procedure-related learning curve, and thus whether these two learning curves matched with each other was observed. Postoperative outcomes in relation to surgeon experience was compared using a Wilcoxon rank sum test and Chi-squared test.

RESULTS

Operative time presented a specific pattern of fewer patient-dependent changes as the case number increased. Spearman's correlation analysis showed the operative time was more affected by the case number (r=-0.73) than the complexity of condition and number of levels hoisted. The operative time-related CUSUM model identified the early (first 29 cases) and late phase (late 41 cases) of the learning process, which was also confirmed by a modified CUSUM model based on surgical procedure. The critical point of the CUSUM model for bilateral osteotomies was at case number 29, and time reduction after the early phase was approximately 34 minutes. Length of hospital stay and blood loss were less during the late phase than during the early phase (p<.05). Although no significant difference was observed in postoperative JOA scores between two phases, patients in the late phase obtained higher recovery rates of neurologic function than those in the early phase (p<.01). There was significant difference in the number of specific errors between the two phases (p=.02). There were no significant differences in overall complication rates between two phases, but a higher incidence of certain complications caused by specific errors was observed in the early phase (p=.02), including CSF leakage, C5 palsy and incomplete decompression.

CONCLUSIONS

We described, for the first time, a detailed learning curve for ACAF surgery. About 29 cases were needed to achieve mastery of ACAF. Once mastered, the surgeon could deal with various OPLL presentations in a universal way regardless of condition complexity and number of surgical levels. Bilateral osteotomies were the most difficult part of ACAF and produced the greatest reduction in time after mastery. We found a close association between specific errors of surgical procedure for ACAF and surgeon experience. Furthermore, certain complications caused by these errors should be on the alert during the early phase of learning ACAF, including CSF leakage, C5 palsy and incomplete decompression.

[Comparison of unilateral biportal endoscopic transforaminal lumbar interbody fusion versus minimally invasive tubular transforaminal lumbar interbody fusion for lumbar degenerative disease]

OBJECTIVE

To compare the clinical and radiological outcomes of unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) and minimally invasive tubular TLIF (MT-TLIF) in treatment of lumbar degenerative diseases.

METHODS

A clinical data of 75 patients with lumbar degenerative diseases, who met the selection criteria between August 2019 and August 2020, was retrospectively analyzed, including 35 patients in the UBE- TLIF group and 40 patients in the MT-TLIF group. There was no significant difference in general data such as gender, age, body mass index, disease type and duration, and surgical segment between the two groups ( P>0.05), which was comparable. The operation time, intraoperative blood loss, hemoglobin (Hb) before operation and at 1 day after operation, the length of hospital stay, incidence of complications, and visual analogue scale (VAS) score of low back and leg pain, Oswestry Disability Index (ODI), Short-Form 36 Health Survey Scale (SF-36 scale), intervertebral disc height (IDH), sagittal Cobb angle, lumbar lordosis (LL), and the intervertebral fusion were compared between the two groups.

RESULTS

Compared with MT-TLIF group, UBE-TLIF group had significantly longer operation time but less intraoperative blood loss and shorter length of hospital stay ( P<0.05). The Hb levels in both groups decreased at 1 day after operation, but there was no significant difference in the difference before and after operation between the two groups ( P>0.05). All patients were followed up, and the follow-up time was (14.7±2.5) months in the UBE-TLIF group and (15.0±3.4) months in the MT-TLIF group, with no significant difference ( t=0.406, P=0.686). In both groups, the VAS score of low back pain, VAS score of leg pain, SF-36 scale, and ODI after operation significantly improved when compared with those before operation ( P<0.05). There was no significant difference between 1 month after operation and last follow-up ( P>0.05). There was no significant difference in the VAS score of low back pain, VAS score of leg pain, and SF-36 scale between the two groups before and after operation ( P>0.05). At 1 month after operation, the ODI in the UBE-TLIF group was significantly better than that in the MT-TLIF group ( P<0.05). At 1 month after operation, IDH, Cobb angle, and LL in both groups recovered when compared with those before operation ( P<0.05), and were maintained until last follow-up ( P>0.05). There was no significant difference in the IDH, Cobb angle, and LL between the two groups at each time point ( P>0.05). Thirty-three cases (89.2%) in the UBE-TLIF group and 35 cases (87.5%) in the MT-TLIF group achieved fusion, and the difference was not significant ( χ ²=0.015, P=0.901). In the UBE-TLIF group, 1 case of intraoperative dural tear and 1 case of postoperative epidural hematoma occurred, with an incidence of 5.7%. In the MT-TLIF group, 1 case of intraoperative dural tear, 1 case of postoperative epidural hematoma, and 1 case of superficial infection of the surgical incision occurred, with an incidence of 7.5%. There was no significant difference in the incidence of complications between the two groups ( χ ²=1.234, P=1.000).

CONCLUSION

Compared with MT-TLIF, UBE-TILF can achieve similar interbody fusion in the treatment of lumbar degenerative diseases, and has the advantages of smaller incision, less bleeding, and shorter length of hospital stay.

Simulation Training in Spine Surgery

Simulated surgery is part of a growing paradigm shift in surgical education as a whole. Various modalities from cadaver models to virtual reality have been developed and studied within the context of surgical education. Simulation training in spine surgery has an immense potential to improve education and ultimately improve patient safety. This is due to the inherent risk of operating the spine and the technical difficulty of modern techniques. Common procedures in the modern orthopaedic armamentarium, such as pedicle screw placement, can be simulated, and proficiency is rapidly achieved before application in patients. Furthermore, complications such as dural tears can be simulated and effectively managed in a safe environment with simulation. New techniques with steeper learning curves, such as minimally invasive techniques, can now be safely simulated. Hence, augmenting surgical education through simulation has great potential to benefit trainees and practicing orthopaedic surgeons in modern spine surgery techniques. Additional work will aim to improve access to such technologies and integrate them into the current orthopaedic training curriculum.

Global and Current Research Trends of Unilateral Biportal Endoscopy/Biportal Endoscopic Spinal Surgery in the Treatment of Lumbar Degenerative Diseases: A Bibliometric and Visualization Study

The study aimed to make a bibliometric analysis of the current research situation in unilateral biportal endoscopy/biportal endoscopic spinal surgery (UBE/BESS). Research data sets were acquired from the Web of Science database. The study chosed “biportal endoscopic spinal surgery” OR “two portal endoscopic spinal surgery” OR “percutaneous biportal endoscopic decompression” OR “unilateral biportal endoscopy” OR “irrigation endoscopic discectomy” as the search terms. The literature search was limited to articles published before March 5, 2021. We only included original articles and reviews. VOS viewer and Citespace software were used to analyze the data and generate visualization knowledge maps. Annual trend of publications, distribution, H‐index status, co‐authorship status, and research hotspots were analyzed. A total of 74 publications met the requirement. The sum number of citations was 31,204, in which 19,336 were no self‐citations. The average citation of all the papers was 21.84 times. The H‐index of all the publications was 85. South Korea's total number of articles was far higher than that of other countries and regions (61, 82.4%), followed by United Arab Emirates, Egypt, and Peoples Republic of China (three, ranking second, accounting for 12.2% of the total). For the most productive authors, Choi ranked first with 21 articles, Kim ranked second with 16 articles, and Heo ranked third with 12 articles. The journal with the greatest number of publications was World Neurosurgery, with a total of 18 (39.1%) papers. Clinics in Orthopedic Surgery ranked second with six (13.0%) papers. In third place, there were fix articles published by Asian Spine Journal and Neurospine, accounting for 21.8% of the total articles. These top three journals accounted for 73.9% of all the papers. Spondylolisthesis and endoscopic decompression were the research hotspots in recent years. The number of publications has showed an upward trend with a stable rise in recent years. South Korea is the country with the highest productivity, not only in quality, but also in quantity. Barun Hosp and Leon Wiltse Mem Hosphave published most articles. Choi is the most productive author. World Neurosurgery is the most productive journal. Spondylolisthesis and endoscopic decompression are the research hotspots in recent years. Indeed, this study provides new insight into the growth and development of UBE/BESS.

Comparing the efficacy and safety of minimally invasive biportal endoscopic spine surgery versus conventional microscopic discectomy in single-level lumbar herniated intervertebral disc (ENDO-BH Trial): a multicenter, prospective, randomized controlled equivalence trial study protocol

Background

Biportal endoscopic surgery has recently been performed in lumbar discectomy, with advantages over conventional surgery, such as less skin scarring and muscle damage. However, the clinical results have not been established. Although previous studies reported no difference between the biportal endoscopic and microscopic discectomy clinical results, the evidence was weak. Therefore, this study aims to evaluate the efficacy and safety of the biportal endoscopic discectomy versus the microscopic discectomy.

Methods

This prospective multicenter randomized controlled equivalence trial is designed to compare the efficacy and safety outcomes of patients who underwent lumbar discectomy using biportal endoscopy or microscopy. We will include 100 participants (50 per group) with a lumbar herniated disc. The primary outcome will be the Oswestry Disability Index (ODI) score 12 months after surgery based on a modified intention-to-treat strategy. The secondary outcomes will include the visual analog scale score for low back and lower extremity radiating pain, the ODI score, the Euro-Qol-5-Dimensions score, surgery satisfaction, walking time, postoperative return to daily life period, postoperative surgical scar, and surgery-related variables, such as postoperative drainage, operation time, admission duration, postoperative creatine kinase, and implementation status of conversion to open surgery. Radiographic outcomes will also be analyzed using magnetic resonance imaging (MRI) or computed tomography (CT) and simple radiographs. Safety will be assessed by evaluating all adverse and severe adverse events and surgery-related effects. The participants will be assessed by a blinded assessor before surgery (baseline) and 2 weeks and 3, 6, and 12 months after surgery.

Discussion

This trial will be the first prospective, multicenter, randomized controlled trial to analyze the efficacy and safety of biportal endoscopic discectomy in lumbar herniated disc.

This trial is designed for evaluating the equivalence of the results between biportal endoscopic and microscopic discectomy including adequate sample size, blinded analyses, and prospective registration to reduce bias. This trial will provide enough data on the effectiveness and safety of biportal endoscopic surgery and will be an important study that allows clear conclusions.

Trial registration

Clinical Research Information Service (cris.nih.go.kr.) (KCT0006191). Registered on 27 March 2021

Perspective on the integration of optical sensing into orthopedic surgical devices

SIGNIFICANCE

Orthopedic surgery currently comprises over 1.5 million cases annually in the United States alone and is growing rapidly with aging populations. Emerging optical sensing techniques promise fewer side effects with new, more effective approaches aimed at improving patient outcomes following orthopedic surgery.

AIM

The aim of this perspective paper is to outline potential applications where fiberoptic-based approaches can complement ongoing development of minimally invasive surgical procedures for use in orthopedic applications.

APPROACH

Several procedures involving orthopedic and spinal surgery, along with the clinical challenge associated with each, are considered. The current and potential applications of optical sensing within these procedures are discussed and future opportunities, challenges, and competing technologies are presented for each surgical application.

RESULTS

Strong research efforts involving sensor miniaturization and integration of optics into existing surgical devices, including K-wires and cranial perforators, provided the impetus for this perspective analysis. These advances have made it possible to envision a next-generation set of devices that can be rigorously evaluated in controlled clinical trials to become routine tools for orthopedic surgery.

CONCLUSIONS

Integration of optical devices into surgical drills and burrs to discern bone/tissue interfaces could be used to reduce complication rates across a spectrum of orthopedic surgery procedures or to aid less-experienced surgeons in complex techniques, such as laminoplasty or osteotomy. These developments present both opportunities and challenges for the biomedical optics community.

Evaluation of the efficacy and safety of conventional and biportal endoscopic decompressive laminectomy in patients with lumbar spinal stenosis (ENDO-B trial): a protocol for a prospective, randomized, assessor-blind, multicenter trial

BACKGROUND

Recent studies on biportal endoscopic spine surgery in patients with lumbar spinal stenosis have reported good clinical results. However, these studies have been limited by the small sample sizes and use of a retrospective study design. Therefore, we aim to compare the efficacy and safety of biportal endoscopic decompressive laminectomy with those of conventional decompressive laminectomy in a multicenter, prospective, randomized controlled trial.

METHODS

This study will include 120 patients (60 per group, aged 20-80 years) with 1- or 2-level lumbar spinal stenosis, who will be recruited from six hospitals. The study will be conducted from July 2021 to December 2024. The primary outcome (Oswestry Disability Index at 12 months after surgery) will be evaluated through a modified intention-to-treat method. The secondary outcomes will include the following: visual analog scale score for low back and lower extremity radiating pain, EuroQol 5-dimensions score, surgery satisfaction, walking time, postoperative return to daily life period, postoperative surgical scars, and some surgery-related variables. Radiographic outcomes will be analyzed using magnetic resonance imaging or computed tomography. All outcomes will be evaluated before the surgery and at 2 weeks, 3 months, 6 months, and 12 months postoperatively. This protocol adheres to the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guidelines for reporting of clinical trial protocols.

DISCUSSION

It is hypothesized that the efficacy and safety of biportal endoscopic and conventional decompressive laminectomy will be comparable in patients with lumbar spinal stenosis. The results of this trial will provide a high level of evidence for the efficacy and safety of the biportal endoscopic technique in patients with lumbar spinal stenosis and facilitate the development of clinical practice guidelines. Furthermore, the results of this study may indicate the feasibility of the biportal endoscopic technique for other types of spinal surgery.

TRIAL REGISTRATION

The ENDO-B trial is registered at Clinical Research Information Service (CRIS, cris.nih.go.kr ) (KCT0006057; April 52,021).

Efficacy and safety of unilateral biportal endoscopy compared with microscopic decompression in the treatment of lumbar spinal stenosis: A protocol for systematic review and meta-analysis

OBJECTIVE

Systematic evaluation of the efficacy and safety of unilateral biportal endoscopic decompression in the treatment of lumbar spinal stenosis.

METHODS

We conducted a systematic literature search and compared the randomized controlled trials (RCTs) and retrospective studies of unilateral biportal endoscopy (UBE) and microscopic decompression (MD) in the treatment of lumbar spinal stenosis from several databases.

RESULTS

Seven studies were included. The results of meta-analysis showed that the operation time of UBE was shorter than that of MD. [SMD = -0.443, 95% CI (-0.717, -0.169), P  = .002]. Compared with MD, the patients' back pain was slighter on the 1st day, 1-2 months and 6 months after UBE. During the long-term follow-up, there was no significant difference in back pain between MD and UBE [SMD = -0.519, 95% CI (-0.934, -0.104), P  = .014]. There was no significant difference in lower limb visual analogue score (VAS) score between UBE decompression and MD [SMD = -0.105, 95% CI (-0.356, 0.146), P  = .412]. The results of meta-analysis showed that the C-reactive protein (CRP) level of UBE was lower than that of MD [weighted mean difference = -1.437, 95% CI (-2.347, -0.527), P  = .002]. There was no significant difference in other clinical effects between the 2 groups.

CONCLUSION

The operation time of UBE was shorter than that of MD, and it was superior to micro decompression in early back VAS score, lower limb VAS score and early postoperative CRP level. There was no statistical difference between UBE and MD in other outcomes.

Minimally invasive transforaminal lumbar interbody fusion using the biportal endoscopic techniques versus microscopic tubular technique

BACKGROUND CONTEXT

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) with microscopic tubular technique is an established surgical procedure with several potential advantages, including decreased surgical-related morbidity, reduced length of hospital stay, and accelerated early rehabilitation. A recently introduced biportal endoscopic technique for spine surgery presents familiar surgical anatomy and can be conducted using a conventional approach with a minimal footprint; it is also applicable to TLIF.

PURPOSE

To compare the clinical and radiological outcomes of biportal endoscopic technique transforaminal lumbar interbody fusion (BE-TLIF) and microscopic tubular technique transforaminal lumbar interbody (MT-TLIF) in patients with single- or two-segment lumbar spinal stenosis with or without spondylolisthesis.

STUDY DESIGN

A retrospective cohort study.

PATIENT SAMPLE

One hundred two participants with neurogenic intermittent claudication or lumbar radiculopathy with single- or two-level lumbar spinal stenosis with or without spondylolisthesis.

OUTCOME MEASURES

Clinical outcomes were assessed using the visual analog scale (VAS) score for the back and leg pain, Oswestry Disability Index (ODI), and the Short Form-36 health survey Questionnaire (SF-36). Demographic data, operative data (total operation time, estimated blood loss, amount of surgical drain, postoperative transfusion, and length of hospital stay), and laboratory results (plasma hemoglobin, serum creatine phosphokinase, and C-reactive protein) were also evaluated. The fusion rate was assessed using the Bridwell interbody fusion grading system. Postoperative complications were also noted.

METHODS

Patients were divided into two groups: group A (BE-TLIF) and group B (MT-TLIF). The clinical outcomes, including VAS-Back and VAS-Leg, ODI, and SF-36 scores, were evaluated at 1 month, 6 months, and 1 year after surgery. Differences in demographics, operative data, and the laboratory and radiological results were assessed between the two groups. The fusion rate was assessed using standard standing lumbar radiographs and computed tomography scans conducted 1 year after surgery.

RESULTS

Seventy-nine patients were analyzed in this study, 47 from group A and 32 from group B. Demographic and operative data were comparable for both the groups. The VAS-Back and SF-36 scores were more significantly improved in group A than in group B at 1 month after surgery. However, there were no significant differences between groups for the mean VAS-Back, VAS-Leg, ODI, and SF-36 scores at 1year after the surgery. Although the total operation time was significantly longer in group A, the estimated blood loss and the amount of surgical drainage was significantly higher in group B (p < .001). There were no between-group differences for the fusion rate and postoperative complications.

CONCLUSION

Both BE-TLIF and MT-TLIF provided equivalent and favorable clinical outcomes and fusion rates. Further large-scale, randomized, controlled trials with long-term follow-ups are warranted.

Learning Curve For Lateral Meniscal Allograft Transplantation: Preventing Meniscal Extrusion

PURPOSE

This study analyzes the large number of lateral meniscal allograft transplantation (LMAT) procedures conducted by a single surgeon over 23 years to determine whether the absolute amount of graft subluxation and the incidence of extrusion are different at the present time compared to the early MAT era.

METHODS

We reviewed 320 cases of LMAT performed by a single surgeon between 1996 and 2019. This cohort was chronologically divided into 8 groups (of 40 subjects). The absolute amount of subluxation was measured by the coronal sections of magnetic resonance images taken 1 year after operation. Subluxation by more than 3 mm was considered as extrusion. The graft extrusion learning curve was plotted in each series using the learning curve cumulative summation test (LC-CUSUM).

RESULTS

Extrusion incidence was 41.6%, and the mean absolute amount of graft subluxation was 3.4 ± 2.2 mm for all subjects. There were significant between-group differences in extrusion incidence and absolute amount of graft subluxation (extrusion incidence, P < .001; absolute amount of graft subluxation, P < .001), and the extension incidence and graft subluxation decreased from Group I (72.5%, 4.6 ± 1.7) to Group VIII (27.5%, 2.5 ± 2.1). LC-CUSUM analysis signaled that the surgeon had achieved predefined acceptable outcomes in avoiding extrusion after 128 cases.

CONCLUSION

The incidence of extrusion and absolute amount of graft subluxation decreased significantly over a period of 23 years, and the surgeon achieved a certain level of proficiency after 128 cases.

LEVEL OF EVIDENCE

Level IV, Case series.