Unilateral Biportal Endoscopy for Decompression of Extraforaminal Stenosis at the Lumbosacral Junction: Surgical Techniques and Clinical Outcomes

How I do it: minimally invasive surgical decompression for lumbosacral extraforaminal stenosis (Far-Out Syndrome)

BACKGROUND

Accurate diagnosis of extraforaminal entrapment of the L5 nerve root, commonly referred to as "far-out syndrome," is challenging due to its unique anatomical characteristics, which differ from those of other lumbar regions. Inadequate decompression may lead to poor outcomes.

METHOD

A minimally invasive paraspinal approach utilizing a tubular retractor was used to decompress extraforaminal entrapment of the L5 nerve root. Procedures and discussions regarding indications, diagnoses, surgical endpoints, and ways to avoid complications were described.

CONCLUSION

Adequate decompression requires sufficient resection of the L5 lower vertebral body bony spur, transverse process, and sacral ala as a ventral margin.

Biportal endoscopic non-facetectomy foraminal decompression and discectomy (ligamentum flavum turn-down technique)

This study introduces a novel biportal endoscopic foraminal decompression technique that minimizes bone removal while ensuring safe and effective nerve root decompression. Leveraging the accessory process as a key surgical landmark, this technique enables precise navigation and controlled turn-down of the ligamentum flavum (LF). A key advantage of this technique is its reduced requirement for bone resection, differing from traditional microscopic or uniportal endoscopic surgeries that often necessitate resection of the lateral isthmus or superior articular process. This technique is particularly beneficial for foraminal and extraforaminal herniated nucleus pulposus cases, where bony decompression needs are relatively lower compared to foraminal stenosis. Using the accessory process as a landmark also enhances surgical precision and reduces the risk of nerve root injury, providing a valuable advantage for less experienced surgeons. Despite these advantages, challenges exist, particularly at the L5-S1 level, where the less prominent accessory process and limited workspace due to anatomical constraints can pose difficulties. In cases of severe bony compression, additional bone removal may be necessary to achieve adequate decompression. In conclusion, the Non-facetectomy LF turn-down technique (non-facetectomy foraminal decompression) offers a safe and effective minimally invasive alternative for treating various foraminal pathologies.

Unilateral biportal endoscopy: review and detailed surgical approach to extraforaminal approach

Foraminal and extraforaminal lumbar disc herniations are common sources of pain and disability. Classic surgical treatments, such as open approach through Witsel technique, often involve resection of the superior articular process to decompress the foraminal space. Unilateral biportal endoscopy (UBE) has emerged as a minimally invasive alternative, providing enhanced visualization and precision while minimizing soft tissue damage. The extraforaminal approach using UBE offers a more effective solution for extraforaminal herniations, requiring less bone resection, reducing the risk of pars fracture and enhancing visualization. This article presents a comprehensive methodology for the extraforaminal approach, supported by an illustrated guide, surgical tips and highlights of UBE's advantages over traditional techniques.

Open Midline Decompression with Ligament Reconstruction for Multiple-Level Spinal Stenosis in Elderly Patients

(1) Background: Multiple lumbar spinal stenosis (LSS) is a degenerative disease that is increasingly prevalent with global aging. Multilevel fusion surgery is burdensome to perform in elderly patients, especially with osteoporosis and underlying disease. This study introduces open midline decompression (OMD) with ligament reconstruction as an alternative stabilization technique for elderly patients with multilevel LSS. (2) Methods: A retrospective review included 42 elderly patients aged 70 or older diagnosed with LSS at three or more levels and who underwent OMD with ligament reconstruction. Pre- and postoperative clinical and radiologic data were analyzed. (3) Results: Thirty-three patients underwent three-level surgeries, and twelve patients underwent four-level surgeries. The mean operative time was 240 ± 42.2 min (74.6 ± 14.9 min per level) with a mean blood loss of 282.9 ± 167.1 cc. Clinical outcome (VAS) and quality of life parameters (SF-12) showed significant improvement after surgery. Postoperative MRI showed sufficient decompression. Dynamic X-rays showed improvement in instability after surgery, but it was statistically insignificant. (4) Conclusions: OMD with ligament reconstruction provides effective neural decompression while preserving the posterior arch and offers soft stabilization with artificial ligaments. It is a safe and viable surgical option for elderly patients with multilevel LSS.

Comparison of Learning Curves and Clinical Outcomes in Unilateral Biportal Endoscopic Spinal Surgery Versus Percutaneous Transforaminal Endoscopic Surgery: A Cumulative Sum Analysis

Purpose

Endoscopic spine surgery has been widely performed to treat degenerative spinal diseases to mitigate the risks and complications associated with traditional open surgery. However, endoscopic procedures pose challenges, including a limited field of view and a restricted operating space, which can affect the surgeon's learning curve. This study aimed to evaluate the learning curves for unilateral biportal endoscopic spinal surgery (UBESS) and percutaneous transforaminal endoscopic surgery (PTES) by performing cumulative sum (CUSUM) analysis and to assess their efficacies in managing degenerative spinal diseases.

Patients and Methods

This retrospective cohort study included 100 consecutive patients who underwent PTES and 100 consecutive patients who received UBESS. CUSUM analysis was conducted to assess the learning curve, with cutoff points used to categorize the early and late phases. These two phases were analyzed in terms of differences in operative time, hospital stay, complications, and patient-reported outcome measures (PROMs). Additionally, PROMs between the PTES and UBESS groups, which were performed by the same surgeon, were compared.

Results

CUSUM analysis revealed that the operative time for PTES and UBESS decreased after 35 and 28 cases, respectively. Both early- and late-phase cases exhibited significant improvement in all PROMs postoperatively. Furthermore, PROMs did not differ between patients who underwent PTES and those who underwent UBESS.

Conclusion

Both procedures achieved comparable clinical outcomes with low complication incidences. However, achieving proficiency in PTES required a learning curve of at least 35 cases, whereas that in UBESS required a minimum of 28 cases.

Percutaneous paravertebral endoscopic decompression for the treatment of far-out syndrome involving the L5 nerve root: technical report and preliminary results

OBJECTIVE

The aim of this study was to describe the technique of percutaneous paravertebral endoscopic decompression for the treatment of far-out syndrome and to analyze the early clinical results of this technique.

METHODS

From April 2021 to June 2023, a retrospective study was conducted on patients with far-out syndrome who underwent percutaneous paravertebral endoscopic decompression at Hospital of Chengdu University of Traditional Chinese Medicine. The Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), and modified MacNab criteria were utilized for the assessment of leg pain, quality of life, and clinical efficacy, respectively. Clinical outcomes were assessed at the day before surgery, 1 day, 1 month, 3 months, 6 months after surgery, and the last follow-up. Meanwhile, the incidence rate of foraminal stenosis, surgery time, and complications were recorded for comprehensive evaluation.

RESULTS

This study included a cohort of 16 patients, with a mean age at the time of surgery of 70.94 ± 4.04 years. The average duration of symptoms was 10.81 ± 5.13 months, while the mean follow-up period lasted for 16.69 ± 5.84 months. The results revealed significant improvements in VAS scores and ODI scores at each time point following the operation (P < 0.05). According to the modified MacNab criteria, excellent or good outcomes were observed in 15 cases (93.70%). Four patients presented with postoperative numbness, which was effectively alleviated through conservative treatment. One case with a fair outcome exhibited residual radicular symptoms.

CONCLUSION

The current technical report presents a successful treatment strategy for far-out syndrome, demonstrating promising preliminary efficacy and safety.

Delta large-channel endoscopy versus unilateral biportal endoscopy decompressive laminectomy for lumbar spinal stenosis: a prospective randomized controlled trial

BACKGROUND

Delta large-channel endoscopy and unilateral biportal endoscopy (UBE) are prominent minimally invasive techniques for treating lumbar spinal stenosis, known for minimal tissue damage, clear visualization, and quick recovery. However, rigorous controlled research comparing these procedures is scarce, necessitating further investigation into their respective complications and long-term effectiveness. This randomized controlled trial aims to compare their perioperative outcomes, focusing on postoperative recovery and complications over time.

METHODS

In total, 101 participants were randomly assigned to Delta large-channel endoscopy group (n = 50) or UBE group (n = 51). Primary measures were Oswestry Disability Index (ODI) scores and operation time. Secondary measures included VAS, EQ-5D, JOA scores, intraoperative blood loss, hospital stay duration, and costs. Perioperative complications such as dural tears, incision infections, hematomas, thrombosis, and reoperation rates were recorded.

RESULTS

The Delta group consistently showed lower mean ODI scores throughout the follow-up than UBE group, with significant differences at 2 weeks postoperative (P = 0.048), though they were not significant by 1 month (P = 0.124), 2 months (P = 0.821) and 3 months (P = 0.350). Operation times were shorter in the Delta group (P < 0.001). Hospitalization costs and intraoperative blood loss were slightly higher in the UBE group (P < 0.001). No significant differences were noted in the other secondary outcomes at various post-surgery intervals, such as VAS, EQ-5D, JOA scores, hospital stay duration and complications.

CONCLUSION

Both techniques are safe and effective when performed by experienced surgeons. Compared to UBE, Delta large-channel endoscopy can shorten surgery time and reduce blood loss, and more importantly, it promotes faster recovery of lumbar function in the early postoperative period.

RESEARCH REGISTRATION UNIQUE IDENTIFYING NUMBER (UIN)

Name of the registry: Chinese Clinical Trial Registry chictr.org.cn. ( http://www.chictr.org.cn/index.aspx ). Unique Identifying number or registration ID: ChiCTR2300076237. Hyperlink to your specific registration (must be publicly accessible and will be checked): https://www.chictr.org.cn/showproj.html?proj=207 ,844.

Learning curve and complications of unilateral biportal endoscopy-unilateral laminectomy bilateral decompression for lumbar spinal stenosis

INTRODUCTION

The unilateral biportal endoscopic (UBE) technique has been widely adopted for treat‑ ment of lumbar disc herniation and lumbar spinal stenosis. Understanding its learning curve, as well as the factors that influence perioperative complications, is crucial for mastering and effectively learning this technique.

AIM

Our aim was to analyze the learning curve of UBE‑unilateral laminectomy bilateral decompression (ULBD) and risk factors associated with perioperative complications.

MATERIALS AND METHODS

Consecutive patients who underwent UBE from June 2021 to December 2023 at the Department of Orthopedics, Beijing Friendship Hospital, were retrospectively analyzed. Baseline information, perioperative data, and preoperative and postoperative subjective scores were recorded for all patients. The learning curve and identified risk factors for complications were analyzed.

RESULTS

A total of 122 consecutive patients who underwent single‑segment UBE‑ULBD were included in this study. The surgical time curve fitting indicated that the surgeon nearly mastered the technique by the 38th case. Consequently, the cohort was divided into 2 distinct phases: a learning phase (cases 1-38) and a mastery phase (cases 39-122). Operative time, estimated blood loss, and drainage volume were higher in the learning phase group than in the mastery phase group, although hidden blood loss in the learning phase group was lower than in the mastery phase group. The visual analogue scale and Oswestry Disability Index scores at the last follow‑up showed significant improvement in both groups as compared with the preoperative period (P <0.05). Complication rate was 7.9% in the learning phase and 3.6% in the mastery phase. Univariate analysis showed that age, body mass index, alcohol consumption, and estimated blood loss were significantly associated with complication rate.

CONCLUSIONS

UBE is an effective minimally‑invasive spinal endoscopic technique for treating lumbar spinal stenosis, offering short time to achieving surgical mastery and a low complication rate.

Comparative Efficacy of Unilateral Biportal Endoscopy vs Traditional Surgery in Lumbar Degenerative Disorders

BACKGROUND Lumbar degenerative diseases, such as lumbar disc herniation, cause significant pain and neurological deficits. Traditional surgeries like posteriior lumbar interbody fusion (PLIF) have drawbacks, including extensive tissue damage. We sought to evaluate the efficacy of unilateral biportal endoscopy (UBE) compared with PLIF, with a focus on clinical outcomes and complication rates. MATERIAL AND METHODS This retrospective study (January 2020 to January 2023) included 109 patients with lumbar degenerative diseases; 53 treated with UBE and 56 with PLIF. We followed Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines with ethical approval. The statistical analyses used t-tests and Chi-square tests (P<0.05). RESULTS The UBE group showed significantly shorter surgery times (107.3±11.2 minutes) and less intraoperative blood loss (50.2±5.7 mL) compared with the PLIF group (113.5±15.7 minutes; 91.3±9.0 mL). Postoperative pain reduction was greater in the UBE group, with a mean Visual Analogue Scale (VAS) score of 3.50±0.85 vs 4.10±0.95 in the PLIF group (P<0.001). The UBE group also had better lumbar function recovery, with higher Japanese Orthopaedic Association scores (19.80±2.30 vs 17.20±2.05; P<0.001). The incidence of postoperative complications was lower in the UBE group (5.67%) compared with the PLIF group (14.29%), although this difference was not statistically significant (P=0.14). CONCLUSIONS UBE could offer significant clinical efficacy in treating lumbar degenerative diseases. It may improve surgical outcomes, reduce postoperative pain, and present a favorable safety profile. These findings suggest UBE might be a viable, minimally invasive option, promoting better recovery and fewer complications.

O-Arm Navigation-Guided Unilateral Biportal Endoscopic Decompression of Far-Out Syndrome

The main aim of this video article is to demonstrate the combined use of O-arm navigation and unilateral biportal endoscopy (UBE) to manage far-out syndrome (FOS). In FOS there is entrapment and compression of the fifth lumbar nerve beyond the foramen and between L5 transverse process and the sacral ala at the lumbosacral junction. Conventional microscopic decompression using a paraspinal approach had been the gold standard for its management. However, the surgery is technically challenging due to the deep location of the pathology and intricate anatomy of extraforaminal space. There have been some published reports of unsatisfactory outcomes with microscopic decompression for FOS. We decided to integrate navigation with UBE to increase precision for the management of FOS. A 70-year-old female presented to us with chief complaint of left lower limb radiculopathy since 1 year. She also complained of numbness and paresthesias in her left leg and foot. She was unable to walk for more than 10 minutes due to pain. Her magnetic resonance imaging scan revealed compression of left L5 nerve root in the extraforaminal region. UBE decompression via paraspinal approach was performed for her under O-arm navigation. She experienced immediate relief of her symptoms in the postoperative period. O-arm-navigation-guided UBE is an effective and safer alternative to microsurgical decompression for the management of FOS. This video demonstrates the step-by-step implementation of O-arm navigation with endoscopy and its precise execution.

Paramedian Unilateral 'Bitubular' Endoscopic Access for a Far Lateral Disc Herniation: A Novel Approach for Far Lateral Lumbar Pathologies

We present a novel technique to approach far lateral lumbar pathologies using a bitubular, biportal endoscopic system and a paramedian approach. Background: Conventional approaches for lumbar far lateral discectomy range from open approaches to newer minimally invasive approaches such as tubular discectomy and single portal endoscopic discectomy. We present a case of a patient suffering with a left L3-4 and left L4-5 extraforaminal disc herniation who was treated successfully with a left sided bitubular, biportal endoscopic 2 level far lateral discectomy. A paramedian 'bitubular' biportal endoscopic approach is safe and effective for far lateral lumbar pathologies with excellent visualisation due to good outflow of irrigation fluid.

Unilateral biportal endoscopic vs. open surgery in the treatment of young obese patients' lumbar degenerative diseases: a retrospective study

Background

Obesity accelerates the development of lumbar disease and increase the risk during surgery. Unilateral biportal endoscopic discectomy (UBE) is a newly developed minimally invasive technique, which refers to the spinal surgery under unilateral double-channel endoscopic surgery. Therefore, the purpose of this study is whether UBE decompression alone can bring good clinical results to young obese patients with lumbar degenerative diseases.

Methods

The patients with lumbar diseases who underwent UBE and open surgery (open discectomy) in our hospital from February 2020 to February 2022 were selected as young (age ≤ 44 years old) and obesity (BMI ≥ 30 kg/m2). The patients were evaluated with VAS, ODI, JOA and modified Macnab score before operation, 1 month, 6 months and 12 months after operation. Nerve root function sensation, muscle strength and tendon reflex were evaluated. The operation time, estimated blood loss, postoperative hospital stay, incidence of postoperative complications and reoperation rate were recorded. MRI quantitative lumbar multifidus muscle (LMM) comparison was performed 12 months after operation.

Results

77 patients were included, and the scores of VAS, ODI and JOA were similar in the two groups during the last follow-up. There were no difference in nerve root function sensation, muscle strength or tendon reflex. However, one month after operation, the VAS back score and ODI improvement in the UBE group were significantly better than those in the open group, which were 2.44 ± 0.97, 33.10 ± 6.78 and 2.93 ± 0.79 and 36.13 ± 5.84, respectively, with a statistically significant difference (p = 0.020 and 0.038). According to the modified Macnab criteria, UBE group, the excellent and good rate was 97.2%. The excellent and good rate of open group was 97.6%. The estimated blood loss and postoperative hospital stay in UBE group (36.81 ± 17.81, 3.92 ± 1.32) were significantly better than those in open group (104.88 ± 31.41, 6.41 ± 1.94), with a statistically significant difference (p = 0.010). There was no significant difference in operation time between the two groups (p = 0.070). The number of complications in UBE group was 2 (5.6%) and open group was 4 (9.8%). The fat infiltration rate of 19.3%+11.0% in UBE group was significantly lower than that of 27.0%±13.9% in open group (p = 0.010).

Conclusion

UBE has the advantage of early recovery in the treatment of lumbar degenerative diseases in young obese patients, and reduces the damage to LMM, so it has a good clinical effect.

Single-Level Unilateral Biportal Endoscopic versus Tubular Microdiscectomy: Comparing Surgical Outcomes and Opioid Consumption

BACKGROUND

Unilateral biportal endoscopic (UBE) microdiscectomy is an emerging minimally invasive surgery technique for treating symptomatic lumbar disc herniation. There is limited literature regarding outcomes. Here, we assess surgical outcomes and pain medication consumption for UBE vs. tubular lumbar microdiscectomy.

METHODS

This was a retrospective cohort study of adult patients undergoing primary, single-level UBE or tubular lumbar microdiscectomy surgery at a high-volume institution between 2018 and 2023. Variables of interest included operative time, complications and reoperations, as well as postoperative opioid and nonopioid pain medication consumption from discharge to 6 months. Opioid consumption was converted to morphine milligram equivalents. Standard statistical analyses were performed for comparative analyses.

RESULTS

One hundred two patients-48 UBE and 54 tubular-were included. Average operative time (minutes) was higher for UBE patients (133.1 UBE vs. 86.6 tubular, P < 0.001), which trended downward over time but did not reach statistical significance (P = 0.07). There were no differences in complication or reoperation rates. Average daily MME was lower from discharge to 2-week follow-up in the UBE group (11.1 v. 14.1, P = 0.02), but were comparative thereafter. Nonopioid medication prescription was lower in the UBE cohort from discharge to 2 weeks (70.8% vs. 92.6%, P = 0.01) and 2 to 6 weeks (52.1% vs. 85.2%, P < 0.001), with no significant differences thereafter.

CONCLUSIONS

UBE microdiscectomy is associated with longer operating times. Both opioid and nonopioid pain medication consumption were lower for UBE patients during the initial postoperative period, perhaps owing to the less-invasive nature of the surgery.

Unilateral biportal endoscopic discectomy via translaminar approach for highly upward-migrated lumbar disc herniation: a technical note and preliminary treatment outcomes

STUDY DESIGN

A technical note and retrospective case series.

OBJECTIVE

Highly upward-migrated lumbar disc herniation (LDH) is challenging due to its problematic access and incomplete removal. The most used interlaminar approach may cause extensive bony destruction. We developed a novel translaminar approach using the unilateral portal endoscopic (UBE) technique, emphasizing effective neural decompression, and preserving the facet joint's integrity.

METHODS

This retrospective study included six patients receiving UBE translaminar discectomy for highly upward-migrated LDHs from May 2019 to June 2021. The migrated disc was removed through a small keyhole on the lamina of the cranial vertebra. The treatment results were evaluated by operation time, hospital stays, complications, visual analog scale (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) score, and modified MacNab criteria.

RESULTS

The mean pre-operative VAS for back pain (5.0 ± 4.9), VAS for leg pain (9.2 ± 1.0), JOA score (10.7 ± 6.6), and ODI (75.7 ± 25.3) were significantly improved to 0.3 ± 0.5, 1.2 ± 1.5, 27.3 ± 1.8, 5.0 ± 11.3 respectively at the final follow-up. Five patients had excellent, and one patient had good outcomes according to the Modified MacNab criteria. The hospital stay was 2.7 ± 0.5 days. No complication was recorded. The MRI follow-up showed complete disc removal, except for one patient with an asymptomatic residual disc.

CONCLUSIONS

UBE translaminar discectomy is a safe and effective minimally invasive procedure for highly upward-migrated LDH with satisfactory treatment outcomes and nearly 100% facet joint preservation.

Lumbar Decompression Using the Far-Lateral Approach: Patient-Reported Outcome is Associated With the Involved Vertebral Level and Coronal Segmental Angle

STUDY DESIGN

A single-centre retrospective study of prospectively collected data.

OBJECTIVE

Analyse factors associated with the patient-reported outcome after far lateral decompression surgery (FLDS) for lumbar nerve root compression using the far-lateral approach.

SUMMARY OF BACKGROUND DATA

To date, no studies have investigated the influence of vertebral level, coronal segmental Cobb angle, and the nature of the compressive tissue (hard or soft) on the patient-reported outcome following FLDS.

PATIENTS AND METHODS

Patients who had undergone FLDS between 2005 and 2020 were included. Coronal segmental angle (CSCA) was measured on preoperative, posteroanterior radiographs. The primary outcome measure was the core outcome measures index (COMI) score at two years' follow-up (2Y-FU). Patients who had undergone microsurgical decompression using a midline approach served as a comparator group.

RESULTS

There were 148 FLDS and 463 midline approach patients. In both groups, there was a significant improvement in the COMI score from preoperative to 2Y-FU ( P <0.0001), with greater improvement in patients treated at higher vertebral levels than in those treated at L5/S1 ( P =0.014). Baseline COMI, American Society of Anesthesiologists grade, body mass index, and low back pain as the "chief complaint" all had a significant association with the two-year COMI score. The nature of compressive tissue showed no association with the COMI score at 2Y-FU. In the FLDS group, there was a statistically significant correlation between the preoperative CSCA and the change in COMI score preoperatively to 2Y-FU ( P <0.001). The association was retained in the multiple regression analysis, controlling for confounders. A one-degree increase in CSCA was associated with a 0.35-point worse COMI score at 2Y-FU ( P =0.003).

CONCLUSION

Treatment of far lateral nerve root compression showed an overall good patient-reported outcome, but with less improvement with advanced CSCA. Modified approaches and techniques might be preferable for levels L5/S1.

Outcomes of FETD versus UBE in the treatment of L5S1 foraminal stenosis: A comparative study

Background

The L5S1 level exhibits unique anatomical features compared with other levels. This makes minimally invasive surgery for L5S1 foraminal stenosis (FS) challenging. This study compared the surgical outcomes of full endoscopic transforaminal decompression (FETD) and unilateral biportal endoscopy with the far-lateral approach (UBEFLA) in patients with L5S1FS.

Methods

In this retrospective study, 49 patients with L5S1FS were divided into two groups. Of these, 24 patients underwent FETD, 25 patients underwent UBEFLA. The study assessed demographic data, leg pain visual analog scale (VAS) score, back pain VAS score, Oswestry Disability Index (ODI), modified MacNab outcome scale, and radiographic parameters including postoperative lateral facet preservation (POLFP).

Results

The Mann-Whitney U test revealed that the UBEFLA group exhibited a higher VAS score for back pain at one week after the operation, whereas the FETD group exhibited a higher leg pain VAS score 6 weeks after the operation. All four undesired MacNab outcomes in the FETD group were attributed to residual leg pain, whereas all five undesired MacNab outcomes in the UBEFLA group were due to recurrent symptoms. Radiographically, the FETD group exhibited greater POLFP.

Conclusions

When L5S1FS is performed, there may be challenges in adequately clearing the foraminal space in FETD. On the other hand, UBEFLA allowed for a more comprehensive clearance. However, this advantage of UBEFLA was associated with spinal instability as a future outcome.

Clinical effects of arthroscopic-assisted uni-portal spinal surgery and unilateral bi-portal endoscopy on unilateral laminotomy for bilateral decompression in patients with lumbar spinal stenosis: a retrospective cohort study

OBJECTIVE

To investigate the clinical effectiveness of Arthroscopic-assisted Uni-portal Spinal Surgery (AUSS) in the treatment of lumbar spinal stenosis.

METHODS

A total of 475 patients with lumbar spinal stenosis from January 2019 to January 2023 were included in this study. Among them, 240 patients were treated with AUSS (AUSS group); the other 235 patients were treated with unilateral bi-portal endoscopy treatment (UBE group). The differences in surgery-related clinical indicators, pain degree before and after surgery, Oswestry Disability Index (ODI), CT imaging parameters of spinal stenosis, and clinical efficacy were compared between the two groups.

RESULTS

Patients in the AUSS group had a shorter operative time than those in the UBE group, and the length of incision and surgical bleeding were less than those in the UBE group, with statistically significant differences (P < 0.05). Before operation, there was no significant difference in the VAS score of low back pain and leg pain between the two groups (P > 0. 05). After operation, patients in both groups showed a significant reduction in low back and leg pain, and their VAS scores were significantly lower than before the operation (P < 0.05). Three months after surgery, the results of CT re-examination in both groups showed that the spinal stenosis of the patients was well improved, and the measurements of lumbar spinal interspace APDC, CAC, ICA, CAD and LAC were significantly higher than those before surgery (P < 0. 05). Besides, the lumbar function of patients improved significantly in both groups, and ODI measurements were significantly lower than those before surgery (P < 0.05).

CONCLUSION

Both AUSS and UBE with unilateral laminotomy for bilateral decompression can achieve good clinical results in the treatment of lumbar spinal stenosis, but the former has the advantages of simpler operation, shorter operation time, shorter incision length, and less surgical blood loss.

Study on early efficacy of UBED and PEID in the treatment of L5/S1 intervertebral disc herniation

INTRODUCTION

This study aimed to compare early efficacy of UBED and PEID in the treatment of L5/S1 IDH.

MATERIAL AND METHODS

Forty-two patients who underwent surgical treatment for L5/S1 IDH were divided into two groups: UBED and PEID. Operation time, complications, VAS/ODI score were recorded. MacNab evaluation was completed one and three months postoperatively.

RESULTS

All patients were successfully operated without infection, nerve injury, or huge hematoma in the spinal canal. There were no significant differences in operation time and hospitalization days between the two groups (p > 0.05). All patients were followed up after the operation and low back/leg pain was significantly reduced. VAS for low back pain, VAS for leg pain, ODI scores in both groups one and three months after the operation were significantly lower than pre-operation (p < 0.05). There were no significant differences between one and three months after the operation in both groups (p > 0.05). There were no significant differences in VAS for low back pain, leg pain, ODI score, and overall efficacy between the two groups one and three months post-operation (p > 0.05).

CONCLUSION

UBED and PEID have very good early efficacy in treating L5/S1 IDH. Because UBED has a wider vision field and more flexible operation, it can be used as a useful complement to PEID.

[Main clinical characteristics of pain in patients with lumbosacral transitional vertebrae]

OBJECTIVE

Based on an analysis of modern medical literature, to study the main clinical characteristics of pain in patients with transitional lumbosacral vertebrae.

MATERIAL AND METHODS

A search was made for articles in the scientific electronic libraries CYBERLENINKA, eLIBRARY, Google Scholar, and the electronic database of biomedical publications PubMed. Sixty-eight scientific publications corresponded to the stated goal.

RESULTS

The review of literature shows that the localization of pain in patients with transitional vertebrae corresponds to the zone of pseudarthrosis between the enlarged transverse process of the LV vertebra and the wing of the sacrum. In most patients, the pain is deep, not superficial. Pain intensity ranges from 3.0 to 8.4, reaching an average of 6.0 on the visual analog scale. Pain can radiate to one of the buttocks and the lower limb. The intensity of pain in the leg at the same time, on average, reaches 5.4 points. The pain syndrome can last for months, the course of the disease acquires a sluggish, undulating character with periodic exacerbations. The causes of exacerbations of pain may be excessive loads on the spine, concomitant vertebrogenic diseases and spinal injuries, excess weight, and in women, a history of pregnancy. Pain management can be either conservative or surgical. The scope of conservative treatment consists of using acupuncture and taking non-steroidal anti-inflammatory drugs. The greatest therapeutic effect is achieved with local injection therapy of analgesics and glucocorticoids at the neoarticulation point. The effectiveness of the course of therapeutic blockades reaches a period from several months to a year. The arsenal of surgical techniques includes pseudoartrectomy, radiofrequency denervation, minimally invasive endoscopic surgery, and transpedicular fusion. In most patients, after surgical treatment, complete relief of pain is noted.

CONCLUSION

The review provides information on the predominant localization of pain in patients with transitional vertebrae, its nature, intensity, irradiation, duration, causes of exacerbation, as well as the effectiveness of the methods of conservative and surgical treatment.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Comparative efficacy of unilateral biportal endoscopy and micro-endoscopic discectomy in the treatment of degenerative lumbar spinal stenosis: a systematic review and meta-analysis

BACKGROUND

Given the inconclusive literature on operative time, pain relief, functional outcomes, and complications, this meta-analysis aims to compare the efficacy of Unilateral Biportal Endoscopy (UBE) and Micro-Endoscopic Discectomy (MED) in treating Degenerative Lumbar Spinal Stenosis (DLSS).

METHODS

A thorough literature search was conducted in accordance with the PRISMA guidelines and based on the PICO framework. The study interrogated four primary databases-PubMed, Embase, Web of Science, and the Cochrane Library-on August 16, 2023, without time restrictions. The search employed a strategic selection of keywords and was devoid of language barriers. Studies were included based on strict criteria, such as the diagnosis, surgical intervention types, and specific outcome measures. Quality assessment was performed using the Newcastle-Ottawa Scale, and statistical analysis was executed through Stata version 17.

RESULTS

The meta-analysis incorporated 9 articles out of an initial yield of 1,136 potential studies. Considerable heterogeneity was observed in surgical duration, but no statistically significant difference was identified (MD = - 2.11, P = 0.56). For VAS scores assessing lumbar and leg pain, UBE was statistically superior to MED (MD = - 0.18, P = 0.013; MD = - 0.15, P = 0.006, respectively). ODI scores demonstrated no significant difference between the two surgical methods (MD = - 0.57, P = 0.26). UBE had a lower incidence of complications compared to those receiving MED (OR = 0.54, P = 0.036).

CONCLUSIONS

UBE and MED exhibited comparable surgical durations and disability outcomes as measured by ODI. However, UBE demonstrated superior efficacy in alleviating lumbar and leg pain based on VAS scores. The findings present an intricate evaluation of the two surgical interventions for DLSS, lending valuable insights for clinical decision-making.

Risk Factors of Restenosis After Full Endoscopic Foraminotomy for Lumbar Foraminal Stenosis: Case-Control Study

OBJECTIVE

To investigate risk factors associated with postoperative restenosis after full endoscopic lumbar foraminotomy (FELF) in patients with lumbar foraminal stenosis (LFS).

METHODS

A single-center, retrospective case-control study was conducted on patients diagnosed with foraminal stenosis who underwent FELF between August 2019 and April 2022. The study included 56 patients, comprising 18 cases and 38 controls. Clinical data, radiologic assessments, and surgical types were compared between the groups. The cutoff values of radiologic parameters that differentiate the 2 groups were investigated.

RESULTS

No significant difference in age, sex distribution, or presence of adjacent segment disease or grade I spondylolisthesis was observed between the groups. Cases had a higher degree of disc wedging angle (DWA) (3.0° ± 1.1° vs. 0.5° ± 1.4°, p < 0.001), larger coronal Cobb angle (CCA) (8.8° ± 5.1° vs. 4.7° ± 2.5°, p = 0.004), and smaller segmental lumbar lordosis (SLL) than controls (11.0 ± 7.4 vs. 18.0 ± 5.4, p = 0.001). Optimal cutoff values for DWA, CCA, and SLL were estimated as 1.8°, 7.9°, and 17.1°, respectively. A significant difference in surgical types was observed between cases and controls (p = 0.004), with the case group having a higher distribution of patients undergoing discectomy in addition to TELF.

CONCLUSION

The study identified potential risk factors for restenosis after FELF in patients with LFS, including higher DWA, larger CCA, smaller SLL angle. We believe that discectomy should be perform with caution during FELF, as it can lead to subsequent restenosis.

Biportal endoscopic paraspinal decompressive foraminotomy for lumbar foraminal stenosis: clinical outcomes and factors influencing unsatisfactory outcomes

BACKGROUND

Lumbar foraminal stenosis (LFS) is an important pathologic entity that causes lumbar radiculopathies. Unrecognized LFS may be associated with surgical failure, and LFS remains challenging to treat surgically. This retrospective cohort study aimed to evaluate the clinical outcomes and prognostic factors of decompressive foraminotomy performed using the biportal endoscopic paraspinal approach for LFS.

METHODS

A total of 102 consecutive patients with single-level unilateral LFS who underwent biportal endoscopic paraspinal decompressive foraminotomy were included. We evaluated the Visual Analogue Scale (VAS) score and the Oswestry Disability Index (ODI) before and after surgery. Demographic, preoperative data, and radiologic parameters, including the coronal root angle (CRA), were investigated. The patients were divided into Group A (satisfaction group) and Group B (unsatisfaction group). Parameters were compared between these two groups to identify the factors influencing unsatisfactory outcomes.

RESULTS

In Group A (78.8% of patients), VAS and ODI scores significantly improved after biportal endoscopic paraspinal decompressive foraminotomy (p < 0.001). However, Group B (21.2% of patients) showed higher incidences of stenosis at the lower lumbar level (p = 0.009), wide segmental lordosis (p = 0.021), and narrow ipsilateral CRA (p = 0.009). In the logistic regression analysis, lower lumbar level (OR = 13.82, 95% CI: 1.33-143.48, p = 0.028) and narrow ipsilateral CRA (OR = 0.92, 95% CI: 0.86-1.00, p = 0.047) were associated with unsatisfactory outcomes.

CONCLUSIONS

Significant improvement in clinical outcomes was observed for a year after biportal endoscopic paraspinal decompressive foraminotomy. However, clinical outcomes were unsatisfactory in 21.2% of patients, and lower lumbar level and narrow ipsilateral CRA were independent risk factors for unsatisfactory outcomes.

Indications for and Outcomes of Three Unilateral Biportal Endoscopic Approaches for the Decompression of Degenerative Lumbar Spinal Stenosis: A Systematic Review

Objective: In this systematic review, we summarized the indications for and outcomes of three main unilateral biportal endoscopic (UBE) approaches for the decompression of degenerative lumbar spinal stenosis (DLSS). Methods: A comprehensive search of the literature was performed using Ovid Embase, PubMed, Web of Science, and Ovid’s Cochrane Library. The following information was collected: surgical data; patients’ scores on the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and Macnab criteria; and surgical complications. Results: In total, 23 articles comprising 7 retrospective comparative studies, 2 prospective comparative studies, 12 retrospectives case series, and 2 randomized controlled trials were selected for quantitative analysis. The interlaminar approach for central and bilateral lateral recess stenoses, contralateral approach for isolated lateral recess stenosis, and paraspinal approach for foraminal stenosis were used in 16, 2, and 4 studies, respectively. In one study, both interlaminar and contralateral approaches were used. L4-5 was the most common level decompressed using the interlaminar and contralateral approaches, whereas L5-S1 was the most common level decompressed using the paraspinal approach. All three approaches provided favorable clinical outcomes at the final follow-up, with considerable improvements in patients’ VAS scores for leg pain (63.6–73.5%) and ODI scores (67.2–71%). The overall complication rate was <6%. Conclusions: The three approaches of UBE surgery are effective and safe for the decompression of various types of DLSS. In the future, long-term prospective studies and randomized control trials are warranted to explore this new technique further and to compare it with conventional surgical techniques.

Decompression via unilateral biportal endoscopy for severe degenerative lumbar spinal stenosis: A comparative study with decompression via open discectomy

Background

Previous studies have shown that the Unilateral Biportal Endoscopy is an effective and safety surgery for sufficient decompression of degenerative lumbar spinal stenosis. However, data are lacking in terms of its benefits when compared with conventional open lumbar discectomy (OLD), especially in patients with severe degenerative lumbar spinal stenosis (DLSS).

Aim

To compare the clini cal outcomes of two types decompressive surgery: unilateral biportal endoscopy-unilateral laminectomy bilateral decompression (UBE-ULBD) and conventional open lumbar discectomy (OLD) in severe degenerative lumbar spinal stenosis (DLSS).

Methods

We retrospectively analyzed patients who underwent UBE-ULBD (n = 50, operated at 50 levels; UBE-ULBD group) and conventional open lumbar discectomy (n = 59, operated at 47 levels; OLD group) between February 2019 and July 2021. All patients were diagnosed with severe stenosis based on the Schizas classification (Grade C or D) on MRI. We compared radiographic and clinical outcome scores [including the visual analog scale (VAS), Oswestry Disability Index (ODI), and Zurich Claudication Questionnaire (ZCQ)] between the 2 groups at 1 year of follow-up. The radiographic evaluation included the cross-sectional area (CSA) of the thecal sac and paraspinal muscles on MRI. Fasting blood was drawn before and 1 and 7 days after the operation to detect creatine kinase (CK). Surgical data perioperative complications were also investigated.

Results

The baseline demographic data of the 2 groups were comparable, including VAS, ODI and ZCQ scores, the cross-sectional area of the thecal sac and paraspinal muscles and creatine kinase levels. The dural sac CSA significantly increased post -operatively in both groups, which confirmed they benefited from comparable decompressive effects. The operative duration in the OLD group was less than the UBE-ULBD group (43.9 ± 5.6 min vs. 74.2 ± 9.3 min, p < 0.05). The OLD group was associated with more estimated blood loss than the UBE-ULBD group (111.2 ± 25.0 ml vs. 41.5 ± 22.2 ml, P < 0.05). The length of hospital stay (HS) was significantly longer in the OLD group than in the UBE-ULBD group (6.8 ± 1.6 vs. 4.0 ± 1.4 days, P < 0.05). The VAS, ODI, and ZCQ scores improved in both groups after the operation. Serum creatine kinase values in the UBE-ULBD group were significantly lower than in the OLD group at 1 day after surgery (108. 1 ± 11.9 vs. 347.0 ± 19.5 U/L, P < 0.05). The degree of paraspinal muscle atrophy in the UBE-ULBD group was significantly lower than in the OLD group at 1 year (4.50 ± 0.60 vs. 11.42 ± 0.87, P < 0.05).

Conclusions

UBE-ULBD and conventional OLD demonstrate comparable short-term clinical outcomes in treating severe DLSS. However, UBE-ULBD surgery was associated with a shorter hospital stay, less EBL and paravertebral muscle injury than OLD surgery.

An overview of lumbar anatomy with an emphasis on unilateral biportal endoscopic techniques: A review

Unilateral biportal endoscopy (UBE) is a major surgical technique used to treat degenerative lumbar diseases. The UBE technique has the advantages of flexible operation, high efficiency, and a large observation and operation space. However, as a typical representative of minimally invasive techniques, UBE still needs to complete a wide range of decompression and tissue resection in a narrow working space, resulting in many surgery-associated injuries. Therefore, it is necessary to reduce complications by familiarity with the anatomy of the lumbar spine. Based on the UBE technique, this review article provides historical and current information on the anatomical structures of the lumbar vertebrae, such as the articular process, pedicle, lamina, ligamentum flavum, nerve root, intervertebral disc, and artery supply.

Learning Curve and Complications of Unilateral Biportal Endoscopy: Cumulative Sum and Risk-Adjusted Cumulative Sum Analysis

OBJECTIVE

The purpose of this study was to investigate the learning curve and complications of unilateral biportal endoscopy (UBE) in the treatment of lumbar disc herniation (LDH) and lumbar spinal stenosis (LSS).

METHODS

This was a retrospective cohort analysis of 197 consecutive patients who received UBE unilateral laminotomy bilateral decompression (UBE-ULBD) or lumbar discectomy (UBE-LD) surgery, including 107 males and 90 females with an average age of 64.83 ± 14.29 years. Cumulative sum (CUSUM) and risk-adjusted cumulative sum analysis (RA-CUSUM) were used to evaluate the learning curve, with the occurrence of complications defined as surgical failure, and variables of different phase of the learning curve were compared.

RESULTS

The cutoff point of learning curve of UBE surgery was 54 cases according to CUSUM analysis. The learning curve of UBE-ULBD and UBE-LD were divided into 3 phases. The first cutoff points were 31 and 12 cases, and the second cutoff point were 67 and 32 cases respectively. With the progress of the learning curve, the operation time and postoperative hospital stays decreased. The visual analogue scale and Oswestry Disability Index at the last follow-up were significantly lower than that before surgery. The incidence of surgical failure was 6.11% and began to decrease after the 89th case based on RA-CUSUM analysis. The surgical failure rate decreased from 10.11% to 2.78 after the 89th case with significant different.

CONCLUSION

UBE surgery is effective in the treatment of LDH and LSS with low incidence of complications. But a learning curve of at least 54 cases still required for mastering UBE surgery.