Transforaminal endoscopic surgery for symptomatic lumbar disc herniations: a systematic review of the literature. Eur Spine J. 2010;19:181-204. [PMID: 19756781 PMCID: PMC2899820 DOI: 10.1007/s00586-009-1155-x]

Endoscopic Treatment of Lumbar Degenerative Disc Disease: A Narrative Review of Full-Endoscopic and Unilateral Biportal Endoscopic Spine Surgery

BACKGROUND

Degenerative lumbar spine disease is the leading cause of disability and work absenteeism worldwide. Lumbar microdiscectomy became the standard treatment for herniated discs and stenotic disease. With the evolution of different techniques, endoscopic spinal surgery emerged to minimize the surgical footprint while providing at least non-inferior results. Currently, two different types of endoscopic spine procedures are dominating the surgical scenario: "Full-Endoscopic" (FE) and Unilateral Biportal Endoscopic" (UBE) Spine Surgery. The aim of this study is to describe and analyze their indications, their technical characteristicswithitsadvantagesanddisadvantagesofbothtechniquesandtheirfuture trends.

METHODS

We performed a narrative review of the most relevant articles published up to August 2023 through a Pub Med search. The search terms " FE Spine Surgery" and " UBE Spine Surgery" were used. The articles selected, were independently reviewed by 3 authors and 55 full text articles were reviewed.

RESULTS

The FE and UBE Spine Surgery techniques were described. The FE technique is performed with a monoportal access under constant saline irrigation. The FE comprises the transforaminal and the interlaminar approaches, and the indication depends from the pathology to treat, and still remains controversial. UBE can approach also the spine from a posterior, postero lateral,and para spinal route. It uses two different ports addressed to a target with continuous irrigation. The process of establishing these two portals is called triangulation.

CONCLUSIONS

FE and UBE spine surgery have demonstrated outcomes comparable to open surgery, minimizing complications and surgical footprint.

Transforaminal Endoscopic Ventral Stenosis Decompression in Calcified Lumbar Disc Herniation: A Long Term Outcome in 79 Patients

BACKGROUND

Calcified lumbar disc herniations (CLDH) causing calcified ventral stenosis pose a therapeutic challenge to the treating surgeon due to their neural adhesions, location, and hardness.

METHODS

This retrospective study analyzed all the cases of CLDH/calcified ventral stenosis managed by transforaminal endoscopic lumbar discectomy with a minimum follow-up of 24 months. The preoperative images were analyzed for the level, migration; and grade (Lee's migration zones), and location (Michigan State University classification). Detailed surgical technique and intraoperative parameters including the duration of surgery and complications have been recorded. The clinical parameters including visual analog scale (VAS), Oswestry disability index (ODI), length of stay in hospital, days of return to basic work, and patient satisfaction index were analyzed. Postoperatively the images were analyzed for the adequacy of decompression.

RESULTS

The mean VAS for back pain and leg pain was 4.7 ± 2.6 (0-9), and 7.45 ± 2.2 (1-10), respectively. The mean preoperative ODI was 78.2 ± 13.2 (63.2-95.6). Nineteen patients (24%) had neurological deficits preoperatively. The mean duration of surgery was 90.5 ± 15.8 (58-131) minutes. Postoperative magnetic resonance imaging revealed adequate decompression in 97.5% (n = 77). The mean duration of hospital stay was 1.05 ± 0.22 (1-2) days, and the postoperative back and leg pain VAS was 1.14 ± 1.2 (0-3) (P < 0.05) and 1.7 ± 0.5 (0-6) (P < 0.05), respectively. The ODI at final follow-up was 6.5 ± 3.7 (2.2-18) (P < 0.05). Neurological recovery occurred in 17 (89.5%) patients and they returned to basic work/jobs in 19.5 ± 3.3 (14-26) days. The mean patient satisfaction index was 1.18 ± 0.47 (1-2) at a mean follow-up of 5.52 ± 2.91 (2-12.75) years.

CONCLUSIONS

Transforaminal endoscopic lumbar discectomy is a complete, safe, and efficacious procedure in patients with CLDH with earlier recovery considering the surgery is performed with the patient being awake.

Access to the Lumbosacral Spine: A Current View

The surgical approach to the lumbosacral spine has been the subject of experimental and scientific anatomical studies since the Hippocratic era. However, it was in the 20th century that, with the evolution of asepsis and antibiotic therapy, spine surgery began to evolve at breakneck speed, and the various possibilities of access roads became objects of development and discussion. As a result, pathologies of the lumbosacral spine can be accessed in different ways and positions, from the traditional posterior approach in the prone position to the anterior, oblique, lateral, and endoscopic approaches. The current article brings state-of-the-art access routes to the lumbosacral spine. This article objective is to elucidate the possibilities of accesses the lumbar spine for any purposes, as decompression, fusion, tumour resections, reconstruction or deformity correction, despites type of implants or implants positioning.

Endoscopic Lumbar Disc Surgery Experience with the TESSYS Technique in 253 Case Series

Background: Herniated lumbar disc (HLD) is a widespread medical problem which can require surgery. Minimally invasive surgical management can represent an extremely valuable option for patients suffering from HLDs. Transforaminal endoscopic lumbar discectomy is an alternative to classical microdiscectomy which was proposed more than two decades ago and has evolved technologically with time. Methods: The transforaminal endoscopic spine system (TESSYS) technique has been introduced in recent years and offers the advantage of performing a controlled foraminal augmentation with full nerve root protection. We started using this technique in 2016 and prospectively evaluated the results of endoscopic TESSYS-based operations performed in a three-year period until the end of 2019. Selection criteria were very strict, and we included only patients with unilateral radicular pain with no instability who failed conservative therapy. Out of the 253 patients operated on in that time span, 183 were available for follow-up evaluation. Results: After surgery, there was a clinically significant improvement of all symptoms which basically lasted in the long-term follow-up. Complications were limited and generally minor. Redo surgery with microdiscectomy was required only in four cases. Obesity did not play a clear negative role in patients' outcome. Conclusions: Endoscopic transforaminal discectomy with the TESSYS technique represents a valuable management option for patients harbouring unilateral herniated lumbar disc located laterally.

Evaluation of Spin in Systematic Reviews and Meta-Analyses of Minimally Invasive Surgical Techniques and Standard Microdiscectomies for Treating Lumbar Disc Herniation

STUDY DESIGN

Systematic review.

OBJECTIVES

Spin in scientific literature is defined as bias that overstates efficacy and/or underestimates harms of procedures undergoing review. While lumbar microdiscectomies (MD) are considered the gold standard for treating lumbar disc herniations (LDH), outcomes of novel procedures are being weighed against open MD. This study identifies the quantity and type of spin in systematic reviews and meta-analyses of LDH interventions.

METHODS

A search was conducted on the PubMed, Scopus, and SPORTDiscus databases for systematic reviews and meta-analyses evaluating the outcomes of MD against other LDH interventions. Each included study's abstract was assessed for the presence of the 15 most common types of spin, with full texts reviewed during cases of disagreement or for clarification. Full texts were used in the assessment of study quality per AMSTAR 2.

RESULTS

All 34 included studies were observed to have at least 1 form of spin, in either the abstract or full text. The most common type of spin identified was type 5 ("The conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studies"), which was observed in ten studies (10/34, 29.4%). There was a statistically significant association between studies not registered with PROSPERO and the failure to satisfy AMSTAR type 2 (P < .0001).

CONCLUSION

Misleading reporting is the most common category of spin in literature related to LDH. Spin overwhelmingly tends to go in the positive direction, with results inappropriately favoring the efficacy or safety of an experimental intervention.

Surgical techniques and perioperative surgical outcomes after discectomy for calcified lumbar disc herniation: a review and meta-analysis

INTRODUCTION

Calcified lumbar disc herniation (CLDH) poses surgical challenges due to longstanding disease and adherence of herniated disc to the surrounding neural structures. The data regarding outcomes after surgery for CLDH are limited. This review was conducted to analyse the surgical techniques, perioperative findings and the postoperative clinical outcomes after surgery for CLDH.

METHODS

PRISMA guidelines were followed whilst conducting this systematic review and meta-analysis. The literature review was conducted on 3 databases (PubMed, EMBASE, and CINAHL). After thorough screening of all search results, 9 studies were shortlisted from which data were extracted and statistical analysis was done. Pooled analysis was done to ascertain the perioperative and postoperative outcomes after surgery for CLDH. Additional comparative analysis was done compared to CLDH with non-calcified lumbar disc herniation (NCLDH) cases.

RESULTS

We included 9 studies published between 2016 and 2022 in our review, 8 of these were retrospective. A total of 356 cases of CLDH were evaluated in these studies with a male preponderance (56.4%). Mean operative time was significantly lower in NCLDH cases compared to CLDH cases. The mean estimated blood loss showed a negative correlation with the percentage of males. Satisfactory clinical outcomes were observed in majority of patients. The risk of bias of the included studies was moderate to high.

CONCLUSION

Surgical difficulties in CLDH cases leads to increase in operative time compared to NCLDH. Good clinical outcomes can be obtained with careful planning; the focus of surgery should be on decompression of the neural structures rather than disc removal.

Transforaminal Endoscopic Lumbar Diskectomy versus Open Microdiskectomy for Symptomatic Lumbar Disk Herniation: A Comparative Cohort Study on Costs and Long-Term Outcomes

BACKGROUND

 Transforaminal endoscopic lumbar diskectomy (TELD) is considered an effective treatment for lumbar disk herniation (LDH). There is a paucity of studies comparing in detail the costs and long-term clinical outcomes of TELD and open microdiskectomy (MD), especially in developing countries. Thus, we sought to provide a multidimensional insight into this matter by comparing the direct costs and long-term outcomes of TELD with those of MD.

METHODS

 The electronic health records of 434 patients with LDH who underwent either TELD or MD were collected from February 2011 to October 2014. Within a 7-year follow-up period, 412 patients, comprising 203 patients treated with TELD and 209 patients treated with MD, were fully evaluated. Patient characteristics, operative time, intraoperative blood loss (IBL), postoperative hospital stay, time to return to work (RTW), perioperative complications, and direct costs were collected. Clinical outcomes were assessed using the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and modified MacNab criteria.

RESULTS

 The postoperative ODI and VAS scores improved significantly in both groups (p < 0.001). In accordance with the modified MacNab criteria, the rate of excellent and good outcomes was 88.67 and 88.03% in the TELD and MD groups, respectively. There were no significant differences between the groups in the clinical outcomes and perioperative complications. However, IBL, hospital stay, and RTW were significantly reduced in the TELD group (p < 0.05). Twenty-one cases in the TELD group and nine in the MD group underwent reoperation due to recurrence (p < 0.05). Total inpatient cost per patient was $1,596 in the TELD group and $1,990 in the MD group (p < 0.05).

CONCLUSION

 TELD for the treatment of symptomatic LDH could be an affordable strategy, providing certain advantages of minimally invasive procedures such as shorter hospital stay and earlier recovery along with comparable clinical outcomes to the conventional surgical method.

Development and validation of a multimodal feature fusion prognostic model for lumbar degenerative disease based on machine learning: a study protocol

INTRODUCTION

Lumbar degenerative disease (LDD) is one of the most common reasons for patients to present with low back pain. Proper evaluation and treatment of patients with LDD are important, which clinicians perform using a variety of predictors for guidance in choosing the most appropriate treatment. Because evidence on which treatment is best for LDD is limited, the purpose of this study is to establish a clinical prediction model based on machine learning (ML) to accurately predict outcomes of patients with LDDs in the early stages by their clinical characteristics and imaging changes.

METHODS AND ANALYSIS

In this study, we develop and validate a clinical prognostic model to determine whether patients will experience complications within 6 months after percutaneous endoscopic lumbar discectomy (PELD). Baseline data will be collected from patients' electronic medical records. As of now, we have recruited a total of 580 participants (n=400 for development, n=180 for validation). The study's primary outcome will be the incidence of complications within 6 months after PELD. We will use an ML algorithm and a multiple logistic regression analysis model to screen factors affecting surgical efficacy. We will evaluate the calibration and differentiation performance of the model by the area under the curve. Sensitivity (Sen), specificity, positive predictive value and negative predictive value will be reported in the validation data set, with a target of 80% Sen. The results of this study could better illustrate the performance of the clinical prediction model, ultimately helping both clinicians and patients.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the medical ethics committee of the Affiliated Hospital of Gansu University of Traditional Chinese Medicine (Lanzhou, China; No. 2022-57). Findings and related data will be disseminated in peer-reviewed journals, at conferences, and through open scientific frameworks.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Register (www.chictr.org.cn) No. ChiCTR2200064421.

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.

Are there correlations between facet joint parameters and lumbar disk herniation laterality in young adults?

OBJECTIVE

We aimed to determine whether there is an association, in young adults, between the occurrence of lumbar disk herniation (LDH) at a given segment and the segment's facet joint parameters [facet orientation (FO) and tropism (FT)]. In addition, associations between facet joint parameters in the corresponding segment and LDH laterality were also investigated.

METHODS

We retrospectively analyzed data from 529 patients who were between 18 and 35 years old, who had experienced single-level LDH (L4-5 or L5-S1) between June 2017 and December 2019, and with<2 years of clinical history. We included an additional 122 patients with no history of LDH as an age-matched control group. LDH were classified by laterality (left-sided, right-sided, or central herniation). At each level, we investigated the relationship between facet joint parameters and herniation laterality.

RESULTS

FO_A values at the L4-L5 level and the L5-S1 level were significantly lower and FT was higher for the LDH group compared with those for the control group. The level at which LDH occurred, FO_L, FO_R, and FT differed significantly among the three groups. There was a significant association between herniationlaterality and FO at the L4-L5 level but not at the L5-S1 level.

CONCLUSIONS

Abnormal facet joint parameters are significantly associated with LDH. Young adults with higher FT should be paid more attention, to prevent the occurrence of LDH. Compared with L5-S1 level, intervertebral disk herniation at the L4-L5 level tended to occur ipsilateral to the side with a lower facet joint angle when FT was present.

Lumbar endoscopic spine surgery for persistent genital arousal disorder/genitopelvic dysesthesia resulting from lumbosacral annular tear-induced sacral radiculopathy

BACKGROUND

Persistent genital arousal disorder/genitopelvic dysesthesia (PGAD/GPD) is characterized by distressing, abnormal genitopelvic sensations, especially unwanted arousal. In a subgroup of patients with PGAD/GPD, cauda equina Tarlov cyst-induced sacral radiculopathy has been reported to trigger the disorder. In our evaluation of lumbosacral magnetic resonance images in patients with PGAD/GPD and suspected sacral radiculopathy, some had no Tarlov cysts but showed lumbosacral disc annular tear pathology.

AIM

The aims were 2-fold: (1) to utilize a novel multidisciplinary step-care management algorithm designed to identify a subgroup of patients with PGAD/GPD and lumbosacral annular tear-induced sacral radiculopathy who could benefit from lumbar endoscopic spine surgery (LESS) and (2) to evaluate long-term safety and efficacy of LESS.

METHODS

Clinical data were collected on patients with PGAD/GPD who underwent LESS between 2016 and 2020 with at least 1-year follow-up. LESS was indicated because all had lumbosacral annular tear-induced sacral radiculopathy confirmed by our multidisciplinary management algorithm that included the following: step A, a detailed psychosocial and medical history; step B, noninvasive assessments for sacral radiculopathy; step C, targeted diagnostic transforaminal epidural spinal injections resulting in a temporary, clinically significant reduction of PGAD/GPD symptoms; and step D, surgical intervention with LESS and postoperative follow-up.

OUTCOMES

Treatment outcome was based on the validated Patient Global Impression of Improvement, measured at postoperative intervals.

RESULTS

Our cohort included 15 cisgendered women and 5 cisgendered men (mean ± SD age, 40.3 ± 16.8 years) with PGAD/GPD who fulfilled the criteria of lumbosacral annular tear-induced sacral radiculopathy based on our multidisciplinary management algorithm. Patients were followed for an average of 20 months (range, 12-37) post-LESS. Lumbosacral annular tear pathology was identified at multiple levels, the most common being L4-L5 and L5-S1. Twenty-two LESS procedures were performed in 20 patients. Overall, 80% (16/20) reported improvement on the Patient Global Impression of Improvement; 65% (13/20) reported improvement as much better or very much better. All patients were discharged the same day. There were no surgical complications.

CLINICAL IMPLICATIONS

Among the many recognized triggers for PGAD/GPD, this subgroup exhibited lumbosacral annular tear-induced sacral radiculopathy and experienced long-term alleviation of symptoms by LESS.

STRENGTHS AND LIMITATIONS

Strengths include long-term post-surgical follow-up and demonstration that LESS effectively treats patients with PGAD/GPD who have lumbosacral annular tear-induced sacral radiculopathy, as established by a multidisciplinary step-care management algorithm. Limitations include the small study cohort and the unavailability of a clinical measure specific for PGAD/GPD.

CONCLUSION

LESS is safe and effective in treating patients with PGAD/GPD who are diagnosed with lumbosacral annular tear-induced sacral radiculopathy.

To Compare the Safety and Efficacy of Conscious Sedation with Dexmedetomidine and Propofol Infusion for Endoscopic Discectomy

OBJECTIVE

Endoscopic discectomy is a minimally invasive, day care spine surgery. Patient comfort is of utmost importance as it is performed under local anaesthesia and in prone position. Propofol and dexmedetomidine are titrable and short-acting and commonly used for conscious sedation. The objectives of the study are to study the effect of dexmedetomidine and propofol infusion on cardiorespiratory parameters and to evaluate the efficacy of dexmedetomidine and propofol infusion for conscious sedation.

METHODS

This is a prospective, randomized, patient-blinded study. Sixty adult patients were randomly recruited to 2 groups of 30 each, to receive an infusion of dexmedetomidine or propofol, titrated to bispectral index score 70-80. The intra-operative cardiorespiratory parameters and level of sedation, postoperative visual analogue scale score, time to discharge from post-anaesthesia care unit, and patient satisfaction were monitored.

RESULTS

Both groups were comparable with respect to demographic parameters and surgical duration. The heart rate was significantly lower with dexmedetomidine whereas the intraoperative mean arterial pressure was higher with dexmedetomidine. Though the level of intraoperative sedation was higher with propofol, the respiratory parameters were comparable. Postoperative visual analogue scale score was significantly higher with propofol.

CONCLUSION

Dexmedetomidine and propofol provide adequate sedation without any cardiorespiratory compromise when used for conscious sedation for minimally invasive spine surgeries performed in prone position. Dexmedetomidine provides an added advantage of postoperative analgesia and better patient satisfaction.

"Inside Disc Out" Discectomy for the Treatment of Discogenic Lumbar Spinal Canal Stenosis under the Intervertebral Foramen Endoscope

OBJECTIVE

Conventional posterior-approach decompression surgeries have a higher risk of nerve root injury and dura laceration. We explore the therapeutic strategy and effect of "inside disc out" discectomy under intervertebral foramen endoscope technique for discogenic lumbar spinal canal stenosis (DLSS) treatment.

METHODS

Twenty-nine patients with DLSS in the responsible segment were treated with "inside disc out" discectomy under intervertebral foramen endoscope technique between October 2017 to October 2019. Lower limb and back pain were recorded before operation, and visual analogue scale (VAS) score and Oswestry disability index (ODI) were recorded for lower limb and back pain at 1, 3, 6, and 12 months postoperatively. The postoperative effects were evaluated using the modified MacNab method for all the patients.

RESULTS

All 29 patients successfully completed the operation. The operation time was 75-120 min, with an average of 90 ± 17 min. Postoperative lumbar CT examinations of all the patients showed full decompression of the spinal cord with no residual pressure. The average follow-up time for all the patients was 13 ± 3.5 months (12-18 months). The VAS score for lower back and lower limb pain was 7.52 ± 1.25 before the operation, and 1.80 ± 0.63, 1.33 ± 0.88, 1.07 ± 0.89, and 0.81 ± 0.51 at 1, 3, 6, and 12 months after the surgery, respectively. The Oswestry dysfunction index was 59.43 ± 10.04 before surgery and 29.67 ± 10.35, 21.13 ± 9.32, 14.52 ± 5.98, and 9.84 ± 4.68 at 1, 3, 6, and 12 months after the surgery, respectively. The VAS score and ODI index of low back and lower limb pain at different time points after the surgery were significantly improved compared to those before the surgery (P < 0.01). The effect of the modified MacNab was excellent in 26 patients, good in two patients, and fair in one patient. The excellent and good rates were 91.4%. Among them, one patient had symptoms of hyperesthesia in the anterior aspect of the thigh and decreased quadriceps muscle strength after lumbar 4/5 segment endoscopic surgery. After symptomatic and conservative treatment, the symptoms disappeared 4 weeks postoperatively, and there were no other serious surgical complications.

CONCLUSIONS

Following the "inside disc out" discectomy under intervertebral foramen endoscope protocols, the risk of nerve injury can greatly be reduced, with good postoperative efficacy. Overall, the procedure is safe and feasible for DLSS treatment.

Effect of medium with moderate temperature on patient's body temperature during percutaneous endoscopic lumbar discectomy

PURPOSE

To explore the influence of irrigating fluid at different temperatures on patients' body temperature and local inflammatory mediators during spinal endoscopy.

METHODS

110 cases of intervertebral foramen surgery in our hospital from January 2019 to October 2021 were randomly divided into control group and observation group. Operations of both groups were performed by the same experienced chief physician. The observation group was irrigated with 37 °C constant temperature saline, while the control group was irrigated at room temperature. The effect was evaluated by monitoring the intraoperative temperature, postoperative VAS score and the levels of inflammatory factors, such as TNF-α, IL-1, IL-6 and IL-10 in drainage fluid.

RESULTS

After 30 min of operation, overall temperature of the control group dropped significantly, and 50 cases (90.9%) had hypothermia, P < 0.05. There was no significant difference in preoperative VAS score between the two groups P > 0.05. The VAS score of observation group was significantly lower than that of control group at 6 h and 1 month after operation, P < 0.05. At 0, 3 and 6 h after operation, the values of TNF-α, IL-1, IL-6 and IL-10 in the observation group were significantly lower than those in the control group (P < 0.05).

CONCLUSIONS

Isothermal flushing solution can reduce the incidence of hypothermia and effectively alleviate local inflammatory reaction.

Treatment of Calcified Lumbar Disc Herniation by Intervertebral Foramen Remolding: A Retrospective Study

Purpose

This study aimed to investigate the use of the percutaneous intervertebral foramen lens technology for secondary molding of the intervertebral foramen in the treatment of calcified lumbar discs.

Methods

The study included 104 patients who were divided into two groups. Group A comprised 50 patients with calcified lumbar disc herniation and group B comprised 54 patients with non-calcified lumbar disc herniation diagnosed by computed tomography and magnetic resonance imaging. Patients underwent a percutaneous endoscopic lumbar discectomy at our hospital from January 1, 2017, to December 31, 2019. Demographic characteristics before the surgery and perioperative outcomes were retrospectively reviewed. The treatment outcome was analyzed using the numerical rating scale (NRS) score, Oswestry Disability Index (ODI) score, and modified Macnab criteria.

Results

Patients in groups A and B showed significant improvement in both the NRS and ODI scores after the surgery and maintained relatively low ODI and NRS scores during subsequent follow-ups. According to the evaluation under the modified MacNab standard, the good–excellent rate of clinical efficacy was 94% in group A and 92.6% in group B at the 3 month follow-up. In group A, one patient developed neck pain during the surgery, which was diagnosed as spinal hypertension syndrome, and the surgery was suspended until the patient’s condition improved. No similar complications occurred in group B. In both the groups, no patient reported any dural leak, infection, or other related complications.

Conclusion

The use of transforaminal remolding technology can significantly improve the symptoms and dysfunction of patients with calcified and non calcified lumbar disc herniation. There are few intraoperative and postoperative complications and have little impact on vertebral stability. It can provide a reference for the treatment of special types of lumbar disc herniation.

Microendoscopic lumbar discectomy with general versus local anesthesia: A systematic review and meta-analysis

Background

While general anesthesia (GA) is the most commonly used anesthetic method during lumbar microendoscopic discectomy (MED), local ± epidural anesthesia (LA) has been gaining popularity as an alternate method. Theoretical advantages of LA include reduced morbidity of anesthesia and improved surgeon-patient communication facilitating less nerve root manipulation and yielding improved surgical outcomes. The objective of this systematic review is to examine the impact of anesthesia type on patient reported outcomes (PROs) and complications with MED.

Methods

A systematic review and meta-analysis of the available literature examining MED performed under GA or LA was performed. The PubMed, EMBASE and SCOPUS databases were searched from inception to August 16, 2021, utilizing strict inclusion and exclusion criteria with all studies reporting greater than 6 months of follow-up and PRO data. PROs including Visual Analog Scale (VAS)-leg/back, Oswestry Disability Index (ODI), Japanese Orthopedic Association (JOA) and/or 36-Item Short Form (SF-36) physical component scores were collected. Complication, recurrent disc herniation, durotomy and reoperation rates as well as surgical factors were collected. All outcomes were compared between pooled studies examining GA or LA. Risk of bias was assessed with the Newcastle-Ottawa Scale.

Results

A total of 23 studies consisting of 2,868 patients (1,335 GA, 1,533 LA) were included in the meta-analysis. There were no significant differences between GA and LA groups in regard to overall complication rate, durotomy rate, recurrent disc herniation rate, reoperation rate, blood loss, or surgical time (p > 0.05). Both groups demonstrated significant improvements in ODI and JOA (p<0.0004), however leg and back VAS was only improved in GA (p<0.0025) and not in LA (p>0.058), and SF-36 only in LA (p=0.003).

Conclusions

Patients undergoing MED under both anesthetic techniques demonstrated significant improvements in ODI and JOA, with no significant differences in complication or reoperation rates. However, patients undergoing GA demonstrated significant improvement in VAS leg and back pain at last follow-up while LA did not. LA may be offered to carefully selected patients and prior studies have demonstrated reduced costs and risks with LA. Conclusions are limited by a high level of study bias and heterogeneity. Further investigation is needed to assess the true effects of GA and LA on outcomes after MED.

Percutaneous Endoscopic Lumbar Discectomy for Recurrent Lumbar Disc Herniation: An Updated Systematic Review and Meta-Analysis

OBJECTIVE

This meta-analysis evaluated surgical outcomes following endoscopic or conventional discectomy for recurrent lumbar disc herniation.

METHODS

Medline, Cochrane, EMBASE, and Google Scholar were search until October 16, 2016 using these terms: recurrent lumbar disc herniation, endoscopic surgery, and discectomy. Randomized controlled trials (RCTs), prospective, retrospective, and cohort studies were eligible for inclusion. Pooled difference in mean (PDM) with 95% confidence interval (CIs) or relative risks (RRs) were calculated using fixed-effects methods.

RESULTS

One RCT and 15 studies were included with a total of 820 patients. Patients received endoscopic surgery experienced shorter operation time than those received conventional surgery (PDM: -52.01, 95% CI: -76.84 to -27.18, P < 0.001). A significantly lower risk in complication was displayed in patients received endoscopic surgery compared to those received conventional surgery (RR: 0.209, 95% CI: 0.076-0.581, P = 0.003). No significant difference in the improvement in VAS (PDM: -2.19, 95% CI: -5.78 to 1.39, P = 0.231), length of stay (PDM: -6.44, 95% CI: -13.76 to 0.89, P = 0.085) and re-recurrence rate (PDM: 0.88, 95% CI: 0.22-3.50, P = 0.861) between groups.

CONCLUSIONS

Endoscopic and conventional discectomy reduced patient pain comparably, but endoscopic discectomy had significantly lower operation time and lower risk in complications, which may impact other outcomes such as recovery and healthcare costs. More studies are needed to confirm our findings.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s43465-022-00636-1.

Technical Tips for Percutaneous Transforaminal Endoscopic Discectomy: A Three-step Maneuver for Puncture and Early Clinical Experience

OBJECTIVE

To investigate the feasibility and efficacy of percutaneous transforaminal endoscopic discectomy (PTED) with three-step maneuver for puncture (TSMP) for lumbar herniated disc (LDH).

METHODS

We performed a retrospective review of 30 patients who underwent PTED using TSMP for LDH and met inclusion criteria from January 2018 to September 2018. The primary outcome, leg or back pain, was assessed using Visual Analogue Scale (VAS). Patient surgical satisfaction was measured at 12 months post surgery using a five-point Likert scale. Potential prognostic factors measured were demographic characteristics, duration of symptom (DOS), and involved levels. Statistical analysis was performed using Fisher exact test and t-test. TSMP is a three-step maneuver that builds on the concept of needle puncture site and trajectory determination based on the principles of Kambin's triangle. First, accurate direction of the puncture is confirmed by inserting the needle horizontally. Then by gradually raising the needle tail in the manner described, the superior articular facet and the intervertebral foramen are sequentially located. Finally, the needle tip slides into the intervertebral foramen to reach the target superior articular facet.

RESULTS

Preoperative mean VAS was 7.6 ± 1.19, which decreased to 1.4 ± 0.97 at 12 months following treatment (P < 0.0001). Rates of surgical satisfaction per Likert scale were as follows: very satisfied and satisfied in 26 patients (86.7%). Three recurrent disc herniations of adjacent segmental levels were observed in the L5-S1 group at eight and 12 months after surgery. VAS scores at 12 months varied significantly between L4-L5 level surgery and L5-S1 level surgery groups (P < 0.01).

CONCLUSION

TSMP is a reliable technique for puncture into the intervertebral foramen.

A Postoperative Phenomenon of Percutaneous Endoscopic Lumbar Discectomy: Rebound Pain

Objective

After percutaneous endoscopic lumbar discectomy (PELD), most patients with lumbar disc herniation (LDH) experience relief from the typical symptoms of low back and leg pain. However, for a small number of patients, these symptoms are relieved immediately after surgery but aggravated soon after, and then relieved after short‐term full rest or conservative treatment. The aim of the study was to demonstrate this short‐term recurrent phenomenon, termed rebound pain.

Methods

A retrospective study was conducted on 144 patients who underwent single‐segment PELD from May 2017 to June 2020. Postoperative patients were divided into a rebound pain group and a non‐rebound pain group. For the former group, general information, symptom characteristics and visual analogue score (VAS) changes in rebound pain were summarized. For both groups, postoperative efficacy was evaluated by recent VAS of low back and leg pain in the remission stage, the Oswestry disability index (ODI) and the modified MacNab criteria at the last follow‐up. Logistic regression analysis was used to identify predictors for rebound pain.

Results

The VAS and ODI exhibited significant improvements at the last follow‐up of average 15.4 months (P < 0.001). The successful outcomes according to the modified MacNab criteria reached 94.4%. A total of 15 patients (10.4%) experienced rebound pain. The typical feature was pain that usually began within 1 month after surgery and lasted for less than 1 month. The symptoms were mainly leg pain with or without low back pain. The range of pain was equal to or less than that before surgery. The symptoms were relieved after conservative treatment. In logistic regression model, postoperative return‐to‐work time > 45 days was found as a protective factor for rebound pain (p = 0.031).

Conclusion

Although rebound pain with multiple characteristics and a short duration had no significant effect on long‐term postoperative efficacy, its high incidence often caused unnecessary concern in both patients and doctors. As a result, careful differentiation of rebound pain from other postoperative complications is needed.

The irony of the transforaminal approach: A comparative cohort study of transforaminal endoscopic lumbar discectomy for foraminal versus paramedian lumbar disc herniation

Transforaminal endoscopic lumbar discectomy (TELD) is useful for soft lumbar disc herniation (LDH). Although the transforaminal approach can reach the foraminal disc zone, the risk of exiting nerve root irritation along the path is considerable. Few studies have assessed the difficulties of TELD for foraminal LDH. The objective of this study is to compare the clinical results of TELD between foraminal or far-lateral LDH and paramedian LDH.Between June 2016 and July 2017, 135 consecutive patients with single-level LDH were treated with TELD for 2 years. Among them, 25 patients had foraminal or far-lateral LDH (foraminal group), and the remaining 110 patients had central or subarticular LDH (paramedian group). Perioperative data and clinical outcomes were evaluated using the visual analog pain scale, Oswestry Disability Index, and modified Macnab criteria.The foraminal group showed a higher rate of significant access pain (24.00% vs 8.19%, P < .05). The foraminal group also had a longer duration of surgery, length of hospital stay, and return to work (all P < .05). Pain scores and functional status were significantly improved in both groups. Although there were no differences in the outcomes at 2 years postoperatively, early pain and disability at 6 weeks were higher in the foraminal group.Ironically, the early clinical results of TELD for foraminal LDH may be less favorable than those for paramedian LDH. Therefore, great care should be taken during TELD for foraminal or far-lateral LDH.

A convenient and stable vertebrae instance segmentation method for transforaminal endoscopic surgery planning

PURPOSE

Transforaminal endoscopic surgery (TES) is effective for treatment of intervertebral disc-related diseases. To avoid injury to the critical structures, preoperative planning is required to find a safe working channel. Therefore, accurate patient-specific vertebral segmentation is important. The purpose of this work is to develop a convenient, stable and feasible lumbar vertebrae segmentation method for TES planning.

METHODS

Based on the chain structure of the spine, an interactive dual-output vertebrae instance segmentation network was designed to segment the specific vertebrae in CT images. First, an initialization locator module was set up to provide an initial locating box. Then the dual-output network was designed to segment two adjacent vertebrae inside the locating box. Finally, iteration was performed until all the expected vertebrae were segmented.

RESULTS

Verification on reconstructed public dataset showed that the vertebral segmentation Dice coefficient was 96.8 ± 1.2% and average surface distance (ASD) was 0.25 ± 0.10 mm. For intervertebral foramen (IVF) region, the Dice coefficient was 96.1 ± 1.5% and ASD was 0.29 ± 0.10 mm. For IVF forming region, the Dice coefficient was 93.4 ± 3.1% and ASD was 0.28 ± 0.13 mm. The evaluation on private dataset showed that more than 90% of the segmentation were suitable for TES planning. For IVF region, the Dice coefficient was 94.4 ± 1.8% and ASD was 0.71 ± 0.49 mm.

CONCLUSION

This work provides a convenient, stable and feasible segmentation method for lumbar vertebrae, IVF region, and IVF forming region. The segmentation can meet the requirement for TES planning.

Evaluation of Effectiveness of Treatment Strategies for Degenerative Lumbar Spinal Stenosis: A Systematic Review and Network Meta-Analysis of Clinical Studies

OBJECTIVE

Lumbar spinal stenosis (LSS) is a common disease in spinal surgery. Many related treatment methods have been reported, but their effectiveness still lacks a systematic comparison. We aimed to evaluate the clinical outcomes related to the efficacy and safety of these treatment strategies via a network meta-analysis.

METHODS

Relevant clinical studies were retrieved from the databases of PubMed, Embase, Web of Science, and Cochrane library updated to July 29, 2020. The data were extracted from the eligible literature and the results were presented as standardized mean differences with 95% confidence intervals (CIs). A network meta-analysis was executed using the netmeta, rjags, and gemtc packages in R software, and Begg and Egger tests were used to assess the publication bias within the included studies.

RESULTS

A total of 21 eligible studies based on 2890 patients with degenerative LSS were included. The newer microdecompression technique (bilateral decompression via unilateral laminotomy [BDUL]) performed better in decreasing the visual analog scale (VAS) score compared with conventional decompressive laminectomy (VAS score back pain, 1.22; 95% CI, 0.28-2.17; VAS score leg pain, 1.39; 95% CI, 0.82-1.96), but its Oswestry Disability Index improvement was slightly inferior to that of posterolateral fusion.

CONCLUSIONS

BDUL could effectively alleviate VAS pain of patients, and had a lower incidence of complications. Although BDUL was slightly inferior to posterolateral fusion in terms of Oswestry Disability Index improvement, the postoperative quality of life of patients treated with BDUL had been significantly improved compared with that before surgery.

Comparison of Percutaneous Endoscopic Lumbar Discectomy and Open Lumbar Discectomy in the Treatment of Adolescent Lumbar Disc Herniation: A Retrospective Analysis

OBJECTIVE

To compare and analyze efficacy and safety of percutaneous endoscopic lumbar discectomy (PELD) and open lumbar discectomy (OLD) for adolescent lumbar disc herniation.

METHODS

Clinical data of 257 patients with single-segment adolescent lumbar disc herniation who underwent surgical treatment from January 2015 to December 2019 were retrospectively collected. The patients were divided into PELD and OLD groups based on the surgical method used. Propensity score matching was performed using preoperative baseline data of patients in both groups, and some patients in both groups were selected for comparative study. Clinical and follow-up data were assessed and compared.

RESULTS

There was no statistically significant difference in preoperative baseline data between the 2 groups of patients after propensity score matching. Visual analog scale and Oswestry Disability Index scores improved in both groups postoperatively and at each follow-up time point (P < 0.05). However, visual analog scale scores on the first postoperative day and Oswestry Disability Index scores at 3 months postoperatively were lower in the PELD group than in the OLD group (P < 0.05). Duration of surgery, intraoperative blood loss, and duration of postoperative hospitalization were lower in the PELD group than in the OLD group (P < 0.05). There was no statistically significant difference between the 2 groups when comparing complication and recurrence rates (P >0.05).

CONCLUSIONS

Both PELD and OLD are effective and safe surgical techniques for treatment of adolescent lumbar disc herniation. However, compared with OLD, PELD is more advantageous for rapid symptom relief and improving postoperative quality of life with a low rate of complications and recurrence.

Percutaneous Transforaminal Endoscopic Discectomy Versus Open Microdiscectomy for Lumbar Disc Herniation: A Systematic Review and Meta-analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVE

To give a systematic overview of effectiveness of percutaneous transforaminal endoscopic discectomy (PTED) compared with open microdiscectomy (OM) in the treatment of lumbar disk herniation (LDH).

SUMMARY OF BACKGROUND DATA

The current standard procedure for the treatment of sciatica caused by LDH, is OM. PTED is an alternative surgical technique which is thought to be less invasive. It is unclear if PTED has comparable outcomes compared with OM.

METHODS

Multiple online databases were systematically searched up to April 2020 for randomized controlled trials and prospective studies comparing PTED with OM for LDH. Primary outcomes were leg pain and functional status. Pooled effect estimates were calculated for the primary outcomes only and presented as standard mean differences (SMD) with their 95% confidence intervals (CI) at short (1-day postoperative), intermediate (3-6 months), and long-term (12 months).

RESULTS

We identified 2276 citations, of which eventually 14 studies were included. There was substantial heterogeneity in effects on leg pain at short term. There is moderate quality evidence suggesting no difference in leg pain at intermediate (SMD 0.05, 95% CI -0.10-0.21) and long-term follow-up (SMD 0.11, 95% CI -0.30-0.53). Only one study measured functional status at short-term and reported no differences. There is moderate quality evidence suggesting no difference in functional status at intermediate (SMD -0.09, 95% CI -0.24-0.07) and long-term (SMD -0.11, 95% CI -0.45-0.24).

CONCLUSION

There is moderate quality evidence suggesting no difference in leg pain or functional status at intermediate and long-term follow-up between PTED and OM in the treatment of LDH. High quality, robust studies reporting on clinical outcomes and cost-effectiveness on the long term are lacking.Level of Evidence: 2.

Invasive Treatments for Low Back Disorders

OBJECTIVE

This abbreviated version of the American College of Occupational and Environmental Medicine's Low Back Disorders guideline reviews the evidence and recommendations developed for invasive treatments used to manage low back disorders.

METHODS

Comprehensive systematic literature reviews were accomplished with article abstraction, critiquing, grading, evidence table compilation, and guideline finalization by a multidisciplinary expert panel and extensive peer-review to develop evidence-based guidance. Consensus recommendations were formulated when evidence was lacking and often relied on analogy to other disorders for which evidence exists. A total of 47 high-quality and 321 moderate-quality trials were identified for invasive management of low back disorders.

RESULTS

Guidance has been developed for the invasive management of acute, subacute, and chronic low back disorders and rehabilitation. This includes 49 specific recommendations.

CONCLUSION

Quality evidence should guide invasive treatment for all phases of managing low back disorders.

Learning Curve for Interlaminar Endoscopic Lumbar Discectomy: A Systematic Review

BACKGROUND

Interlaminar endoscopic lumbar discectomy (IELD) is an efficient surgical treatment for lumbar disc herniation. However, this minimally invasive procedure requires a considerable learning curve that has not yet been standardized. This review aimed to evaluate the learning curve's characteristics, including the cutoff point required to achieve technical proficiency and to discuss appropriate training methods.

METHODS

We systematically searched the core databases (PubMed, Embase, and Cochrane Library) for clinical studies that evaluated the learning curve using quantitative data. We performed a quality assessment using the Newcastle-Ottawa scale. We also compared descriptive statistics, including operative time and other variables before and after the cutoff point.

RESULTS

Six studies reporting 302 cases of IELD were selected from 7188 screened articles. The cutoff point was randomly set in 3 studies and determined as the curve's asymptote in 3 studies. The mean value for the cutoff point was 22.17 ± 12.40 cases (range: 10-43 cases) and mainly determined based on the operative time, which was shorter in the late group than that in the early group (P < 0.05). The cutoff points were not significant for patient outcome parameters such as pain score, functional result, surgical failure, or complications.

CONCLUSIONS

The evidence of published studies regarding the learning curve for the IELD technique is insufficient. The reported cutoff points may be significant only for task efficiency. Moreover, they may not represent the asymptote of the curve. Future studies should evaluate the actual plateau points using patient outcome data.

Minimum Seven-Year Follow-Up Outcomes of Percutaneous Endoscopic Lumbar Discectomy for Lumbar Degenerative Disease

Purpose

To investigate the long-term (> 7 years) clinical outcomes of percutaneous endoscopic lumbar discectomy for lumbar degenerative disease to address postoperative problems including postoperative dysesthesia (POD), residual back pain and segmental instability.

Methods

Inclusion and exclusion criteria were established. All patients who met the above criteria were treated by PELD using the transforaminal approach. Limited discectomy was performed to preserve the disc material in the intervertebral space as much as possible. The Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score for back pain (VAS-B) and leg pain (VAS-L) and Modified MacNab’s criterion were used for clinical evaluation. Radiographic parameters including height of intervertebral disc and segmental instability were also evaluated.

Results

Forty-two patients (24 men and 18 women) who met our inclusion and exclusion criteria were included in our study. The average follow-up period was 95.71±5.63 months (ranging from 87 to 105 months). There were no neurological complications associated with the operation. POD was found in 14.29% of patients, while only 2 patients (4.76%) complained of mild dysesthesia at final follow-up. Two patients (4.76%) required revision surgery during the follow-up period. The final follow-up ODI, JOA score, VAS-B and VAS-L were significantly better than preoperative values. The average disc-height ratio was 84.52±5.66% of the preoperative disc height. No instability at the operation level was noted at final follow-up.

Conclusion

Our study showed that PELD using the transforaminal approach can provide favorable results after a long-term follow-up period. POD is a common complication at initial prognosis. Limited discectomy can preserve the disc height well and minimize the risk of residual back pain.

SURGERY FOR LUMBAR DISC HERNIATION: OPEN X MINIMALLY INVASIVE TECHNIQUE

ABSTRACT Objective: In Brazil, there are no studies comparing endoscopic treatment of lumbar disc herniation with the conventional open technique in SUS (Unified Health System) with regard to hospitalization time and complications occurring within one year, which is the objective of this study. Methods: A survey of 32 surgeries performed in 2019 (11 open and 21 endoscopic) to evaluate pain parameters before and after surgery (VAS), days of hospitalization, and complications. The data were submitted to statistical analysis (ANOVA) using the Kruskal-Wallis test. Results: Fourteen patients were female and eighteen were male, with a mean age of 41.35 years (p> 0.05 between sexes). The pre- and postoperative VAS for pain radiating to the lower limb were similar between the groups: 8.5 ± 0.82 with the open technique and 8.19 ± 1.15 with endoscopic technique. In both groups there was an improvement in the pain pattern with a significant reduction in the VAS (p < 0.05) and there was no statistical relevance between the groups in terms of pain improvement. There was statistical relevance between the groups in the comparison of days of hospitalization required, with the group submitted to endoscopic surgery having a lower number of days. The complications reported were compatible with those found in the literature (postoperative dysesthesia, new herniation). Conclusions: The endoscopic technique resulted in an important reduction in the number of days of hospitalization, a factor with a high impact on the costs of any surgical procedure, which can be a determining factor in the feasibility of minimally invasive techniques. Level of evidence IV; Therapeutic Study.

Should adjacent asymptomatic lumbar disc herniation be simultaneously rectified? A retrospective cohort study of 371 cases that received an open fusion or endoscopic discectomy only on symptomatic segments

BACKGROUND CONTEXT

In the treatment of multiple disc herniations, the decision of whether to include the presumed asymptomatic lumbar disc herniation (asLDH) at adjacent segments remains uncertain. On the one hand, the untouched asLDH might soon become symptomatic and require treatment. On the other hand, additional surgery involving more segments will introduce greater risk, complications, and cost.

PURPOSE

To investigate the prognosis of untreated asLDH after open fusion or percutaneous endoscopic lumbar discectomy (PELD) on symptomatic lumbar disc herniation (LDHs) in patients.

STUDY DESIGN

This is a retrospective cohort study.

PATIENT SAMPLE

A total of 371 patients with multiple disc herniations who underwent open discectomy and fusion or PELD only for symptomatic levels from January 2012 to July 2018 were included.

OUTCOME MEASURES

The primary outcome of interest was the development of symptomatic LDH at the previous asLDH of both groups that required reoperation. A second analysis was performed to compare the reoperation rate due to deterioration of asLDH among different severity grades of herniation. Reoperation rates of the original surgery at the symptomatic segment in both fusion and PELD groups were also reviewed.

METHODS

The patients were divided into two groups based on the surgical procedure, with 264 patients undergoing fusion surgery and 107 patients undergoing PELD. Clinical and imaging follow-ups were performed at routine intervals for more than 3 years. The reoperation rates due to deterioration of previously asLDH and failure of original surgery were investigated and compared between the two groups, as well as among the different severity grades of herniation.

RESULTS

The follow-up times were 48.2±24.2 and 41.1±17.5 months for the fusion and the PELD groups, respectively. The overall reoperation rate at the previous adjacent asLDH was 6.7% (25/317). According to the severity of the asLDH, a higher grade of asymptomatic herniation yielded a significantly higher rate of reoperation rate in both groups. If the nerve root was displaced by disc material prominently (nG2), the reoperation rate of asLDHs was 42.9% (3/7) in the fusion group and 20% (3/15) in the PELD group. Twenty out of 264 patients (7.6%) in the fusion group and 5 out of 107 patients (4.7%) in the PELD group required reoperation due to deterioration of asLDH. Reoperation rates due to failure of the original surgery were 7.6% (20/264) in the fusion group and 8.4% (9/107) in the PELD group.

CONCLUSIONS

With multilevel LDHs, if the asLDH is left untreated, the reoperation rate is closely related to the degree of herniation. When confronting an asLDH graded as G2, a high possibility of reoperation should be clearly discussed with the patient, regardless of open fusion or PELD techniques. Considering that fusion and minimally invasive nonfusion techniques did not yield significantly different overall reoperation rates, ongoing degeneration seemed to have a greater contribution in terms of the deterioration of asLDH.

The Current State of Cervical Endoscopic Spine Surgery: an Updated Literature Review and Technical Considerations

Introduction: Endoscopic spine surgery has become one of the representative minimally invasive spine surgeries (MISS), especially in the lumbar spine. Full-endoscopic procedures using a working channel endoscope for cervical degenerative spine disease have been reported as practical and feasible. This review aimed to summarize the updated techniques of and studies about cervical endoscopic surgery. Areas covered: An extensive search of PubMed was performed for randomized controlled trials (RCTs) or comparative cohort studies on the full-endoscopic cervical procedure. All the 236 articles found were screened and categorized. Only two RCTs and four cohort studies finally met the search criteria. Regarding the surgical techniques, there are four categories according to the approach method: 1) anterior endoscopic cervical discectomy (AECD); 2) anterior endoscopic cervical transcorporeal decompression (AECTcD); 3) posterior endoscopic cervical foraminotomy and discectomy (PECFD); and 4) posterior endoscopic cervical laminotomy (PECL). Expert opinion: Cervical endoscopic surgery provides comparable clinical results with MISS benefits, such as shorter operative time, less bleeding, and earlier recovery time. However, spine surgeons are not yet familiar with most of these techniques; moreover, supportive evidence is minimal. Technical evolution is still ongoing in an effort to make the procedure more practical.

Evaluation of Percutaneous Transforaminal Endoscopic Discectomy in the Treatment of Lumbar Disc Herniation: A Retrospective Study

OBJECTIVE

The objective of the present study was to evaluate the safety and efficacy of percutaneous transforaminal endoscopic discectomy (PTED) and open fenestration discectomy (OFD) in the treatment of lumbar disc herniation (LDH).

METHODS

Patients in our hospital with LDH who received PTED (n = 71) and OFD (n = 39) from 2013 to 2014 were retrospectively studied. Patient information, including age, gender, visual analogue scale (VAS) score for low back pain and leg pain, body weight, height, Oswestry disability index (ODI), Japanese Orthopedic Association (JOA), and recurrence, was collected. The patients in the two groups were followed up for an average of 63 months after surgery.

RESULTS

A total of 136 patients completed the operation and 110 patients were followed up completely. There was no significant difference in baseline data between the two groups (P > 0.05). The postoperative low back pain, leg pain, ODI, and JOA of the two groups were better than those preoperatively (P < 0.05). One week after surgery, the recovery of PTED patients was better than that of OFD. The ODI score of the PTED group was lower than that of the OFD group (10 [8, 12] vs 14 [11, 16]; P < 0.05), the waist VAS score of the PTED group was lower than that of the OFD group (2 [2, 3] vs 3 [2, 4]; P < 0.05), the leg VAS score of the PTED group was lower than that of the OFD group (1 [0,1] vs 1 [1, 2]; P < 0.05), while the JOA score of the PTED group was higher than that of OFD group [19(16, 20) vs 12(10, 17); P < 0.05]. There were no significant differences in ODI, JOA, waist and leg VAS scores between the two groups at 1 month after surgery and at subsequent follow-up (P > 0.05). At the end of the follow up, 89.7% (35/39) of patients in the OFD group had excellent improvement in the JOA score, and 88.7% (63/71) of patients in the PTED group had an excellent improvement. There was no significant difference between the two (P > 0.05). There was also no significant difference in the recurrence rate between the two groups [(5/71) vs (3/39); P > 0.05]. [Correction added on 05 March 2021, after first online publication: "3/29" was amended to "3/39" in the preceding sentence.] CONCLUSION: Both PTED and OFD can achieve good mid-term efficacy in the treatment of LDH but PTED has certain advantages, including the small incision, a shorter hospital stay, and quicker, earlier recovery. However, prospective randomized controlled studies with a larger sample size are needed.

Clinical outcomes of transforaminal endoscopic lateral recess decompression by using the visualized drilled foraminoplasty and visualized reamed foraminoplasty: a comparison study

Background

Lateral recess stenosis (LRS) is a common degenerative disease in the elderly. Since the rise of comorbidity is associated with increasing age, transforaminal endoscopic lateral recess decompression (TE-LRD) is advocated. The objective of this study was to compare the clinical outcomes of TE-LRD in patients with LRS via visualized drilled foraminoplasty (VDF) or visualized reamed foraminoplasty (VRF) technique.

Methods

A total of 45 and 42 consecutive patients with limp or unilateral radiculopathy symptoms underwent TE-LRD using the VDF and VRF technique, respectively. The radiation exposure and operation time, time to return to work, and complications were compared between two groups. Their clinical outcomes were evaluated with the visual analogue scale (VAS) leg pain score, VAS back pain score, Oswestry Disability Index (ODI) and modified MacNab’s criteria.

Results

The average values of radiation exposure and operative time in the VDF group were significantly higher than those in the VRF group (P <  0.05). The postoperative VAS and ODI scores in both groups were significantly improved compared with those before the operation (P <  0.05). In addition, the VAS score of the leg pain and ODI score in the VRF group were significantly lower than those in the VDF group at the 1-week follow-up (P <  0.05). The good-to-excellent rates of the VDF group and VRF group were 88.89 and 90.48%, respectively, whereas the complication occurrence rates were 6.67 and 4.76% in the VDF group and VRF group, respectively.

Conclusions

TE-LRD performed by using VRF technique can be applied to treat LRS safely and effectively with short radiation exposure and operation time. This technique was comparable to the VDF technique with improved VAS leg pain and ODI scores in the short period after the operation. However, potential complications and risks still need to be considered.

Comparison of postoperative outcomes between patients with positive and negative straight leg raising tests who underwent full-endoscopic transforaminal lumbar discectomy

Full-endoscopic transforaminal lumbar discectomy (FETD) is increasingly used in patients with lumbar disc herniation (LDH). There is little knowledge on the related factors, including the straight leg raising test (SLR), that influence the operation. Consecutive patients with LDH who came to our hospital from August 2015 to September 2016 and underwent FETD surgery were included. Four kinds of scores, including the VAS (lumbar/leg), ODI and JOA values, were measured and reassessed after FETD to assess the surgical outcomes. There was a statistically significant difference between the scores before surgery and at each postoperative follow-up. In addition, the increase in the JOA score postoperatively was statistically significant compared with that before surgery. There were statistically significant differences among the three subpopulations [patients considered SLR positive (0°-30°), SLR positive (31°-60°) and SLR negative (61°-)] in the changes in the VAS (leg), ODI and JOA values. However, there were no statistically significant differences among the three subpopulations [patients considered SLR positive (0°-30°), SLR positive (31°-60°) and SLR negative (61°-)] in the changes in VAS score (lumbar). FETD showed great effectiveness in treating patients with lumbar disc herniation. Patients who were SLR negative may receive greater benefit from FETD.

Combined Effects of Graded Foraminotomy and Annular Defect on Biomechanics after Percutaneous Endoscopic Lumbar Decompression: A Finite Element Study

Percutaneous endoscopic technology has been widely used in the treatment of lumbar disc stenosis and herniation. However, the quantitative influence of percutaneous endoscopic lumbar decompression on spinal biomechanics of the L5–S1 lumbosacral segment remains poorly understood. Hence, the objective of this study is to investigate the combined effects on the biomechanics of different grades of foraminotomy and annular defect for the L5–S1 segment. A 3D, nonlinear, detailed finite element model of L4–S1 was established and validated. Changes in biomechanical responses upon stimulation to the intact spine during different degrees of resection were analyzed. Measurements included intervertebral rotation, intradiscal pressure, and the strain of disc structure under flexion, extension, left/right lateral bending, and left/right axial rotation under pure bending moments and physiological loads. Compared with the intact model, under prefollower load, annular defect slightly decreased intervertebral rotation by −5.0% in extension and 2.2% in right axial rotation and significantly increased the mean strain of the exposed disc by 237.7% in all loading cases. For right axial rotation, unilateral total foraminotomy with an annular detect increased intervertebral rotation by 29.5% and intradiscal pressure by 57.6% under pure bending moment while the maximum corresponding values were 9.8% and 6.6% when the degree of foraminotomy was below 75%, respectively. These results indicate that percutaneous endoscopic lumbar foraminotomy highly maintains spinal stability, even if the effect of annular detect is taken into account, when the unilateral facet is not totally removed. Patients should avoid excessive extension and axial rotation after surgery on L5–S1. The postoperative open annular defect may substantially increase the risk of recurrent disc herniation.

Learning Curve for Transforaminal Percutaneous Endoscopic Lumbar Discectomy: A Systematic Review

BACKGROUND

Transforaminal percutaneous endoscopic lumbar discectomy (TPELD) has become an alternative and minimally invasive surgical technique for soft lumbar disc herniation. However, the learning curve has been relatively long and difficult. In the present study, we have summarized the characteristics of the learning curve of TPELD, including the number of cases required to achieve technical proficiency, and discussed the strategies to improve the learning curve.

METHODS

The PubMed, Embase, Cochrane Library, and KoreaMed databases were searched for reports describing the learning curve for TPELD. Clinical studies involving human patients and evaluating the learning curve of TPELD with quantitative data were included. A strict quality assessment was completed, and descriptive statistics were calculated.

RESULTS

Of the 6884 screened titles and abstracts, 10 full-text reports, including 958 cases, were included in the analysis. All were cohort studies, which were grouped into early and late groups according to surgeon experience with TPELD. The most commonly used cutoff to differentiate between these groups was 20 (mean, 24.70 ± 18.99 cases; range, 10-72 cases). The most widely used measure was the operative time. Although most studies had reported better results in the operative time or pain scores in the late group, only 1 study had proposed a bona fide learning curve.

CONCLUSIONS

We found insufficient evidence to support a cutoff point of 20 or other numbers of cases for determining when the learning curve has reached a plateau. Therefore, these numbers should be interpreted with great care, and high-quality prospective studies evaluating the actual learning curve are required.

A Historical Review of Endoscopic Spinal Discectomy

As an essential component of minimally invasive spine surgery, endoscopic spine surgery (ESS) has continuously evolved and has been accepted as a practical procedure by the worldwide spine community. Especially for lumbar disc herniation (LDH), the percutaneous endoscopic or full-endoscopic discectomy technique has been scientifically proven through randomized controlled trials and meta-analyses to be a good alternative to open discectomy. The initial concept of endoscopic spine discectomy was concerned with indirect disc decompression using various instruments such as blind forceps, a nucleotome, laser, radiofrequency coblation, and some chemical agents. The main surgical field has been shifted from the intradiscal space to the epidural space. Precise and selective discectomy for extruded LDH in the epidural space under high-quality endoscopic visualization is now feasible. Furthermore, the medical applications of ESS is broadening to include spinal stenosis, segmental instability, infection, and even intradural lesions. In this review article, I describe the history of endoscopic spine discectomy and decompression techniques, as well as evolution of the paradigm. This history may help indicate the future of practical ESS.

Feasibility of Using Intraoperative Neuromonitoring in the Prophylaxis of Dysesthesia in Transforaminal Endoscopic Discectomies of the Lumbar Spine

(1) Background: Postoperative nerve root injury with dysesthesia is the most frequent sequela following lumbar endoscopic transforaminal discectomy. At times, it may be accompanied by transient and rarely by permanent motor weakness. The authors hypothesized that direct compression of the exiting nerve root and its dorsal root ganglion (DRG) by manipulating the working cannula or endoscopic instruments may play a role. (2) Objective: To assess whether intraoperative neurophysiological monitoring can help prevent nerve root injury by identifying neurophysiological events during the initial placement of the endoscopic working cannula and the directly visualized video endoscopic procedure. (3) Methods: The authors performed a retrospective chart review of 65 (35 female and 30 male) patients who underwent transforaminal endoscopic decompression for failed non-operative treatment of lumbar disc herniation from 2012 to 2020. The patients’ age ranged from 22 to 86 years, with an average of 51.75 years. Patients in the experimental group (32 patients) had intraoperative neurophysiological monitoring recordings using sensory evoked (SSEP), and transcranial motor evoked potentials (TCEP), those in the control group (32 patients) did not. The SSEP and TCMEP data were analyzed and correlated to the postoperative course, including dysesthesia and clinical outcomes using modified Macnab criteria, Oswestry disability index (ODI), visual analog scale (VAS) for leg and back pain. (4) Results: The surgical levels were L4/L5 in 44.6%, L5/S1 in 23.1%, and L3/L4 in 9.2%. Of the 65 patients, 56.9% (37/65) had surgery on the left, 36.9% (24/65) on the right, and the remaining 6.2% (4/65) underwent bilateral decompression. Postoperative dysesthesia occurred in 2 patients in the experimental and six patients in the control group. In the experimental neuromonitoring group, there was electrodiagnostic evidence of compression of the exiting nerve root’s DRG in 24 (72.7%) of the 32 patients after initial transforaminal placement of the working cannula. A 5% or more decrease and a 50% or more decrease in amplitude of SSEPs and TCEPs recordings of the exiting nerve root were resolved by repositioning the working cannula or by pausing the root manipulation until recovery to baseline, which typically occurred within an average of 1.15 min. In 15 of the 24 patients with such latency and amplitude changes, a foraminoplasty was performed before advancing the endoscopic working cannula via the transforaminal approach into the neuroforamen to avoid an impeding nerve root injury and postoperative dysesthesia. (5) Conclusion: Neuromonitoring enabled the intraoperative diagnosis of DRG compression during the initial transforaminal placement of the endoscopic working cannula. Future studies with more statistical power will have to investigate whether employing neuromonitoring to avoid intraoperative compression of the exiting nerve root is predictive of lower postoperative dysesthesia rates in patients undergoing videoendoscopic transforaminal discectomy.

Outcome of lumbar lateral recess stenosis with percutaneous endoscopic transforaminal decompression in patients 65 years of age or older and in younger patients

Lateral recess stenosis is a common pathology causing clinical syndromes in the elderly population, and there is some concern regarding the number of comorbidities that can occur when performing surgery for this condition in the elderly. However, little research has focused on the issues related to older age, and limited data is available to help the clinician counsel elderly patients undergoing percutaneous endoscopic transforaminal decompression. The present study aimed to explore the safety and efficacy of percutaneous endoscopic transforaminal decompression for lumbar degenerative disease in elderly patients with lumbar lateral recess stenosis and to determine whether age and comorbidity affect the outcome and complication rate.We identified 117 patients in our patient database who underwent percutaneous endoscopic transforaminal decompression for single-level lumbar lateral recess stenosis. Data regarding the Oswestry Disability Index and visual analog scale for back and leg pain were collected preoperatively, postoperatively, and at the last follow-up. Other data, including preoperative comorbidities, operation time, and intraoperative and postoperative complications, were recorded.The average follow-up period was 29.9 ± 5.5 months, with a mean age of 69.8 ± 5.4 years in elderly patients (group A) and 50.4 ± 6.4 years in younger patients (group B). Group A had a higher percentage of comorbidity than group B (83.9% vs 18.0%, P < .001). Both visual analog scale scores for leg pain and Oswestry Disability Index were significantly improved in the 2 groups, and no difference was found between the groups regarding both parameters (P >.05). The elderly patients had the same high rate of favorable outcomes as group B (P > .05). Moreover, there was no difference in surgical complications, recurrence, and neurologic deficit recovery rate between both groups. No major complications or perioperative deaths occurred in both groups.The present study demonstrates that percutaneous endoscopic transforaminal decompression for lateral recess stenosis in elderly patients may be a reasonable treatment associated with substantial benefit.

Bi-needle technique versus transforaminal endoscopic spine system technique for percutaneous endoscopic lumbar discectomy in treating intervertebral disc calcification: a propensity score matched cohort analysis

OBJECTIVE

The aim of this study was to evaluate the clinical results of a Bi-needle technique and conventional transforaminal endoscopic spine system (TESSYS) technique for percutaneous endoscopic lumbar discectomy (PELD) in treating patients with intervertebral disc calcification (IDC).

BACKGROUND

PELD has gained acceptance for treating patients with IDC. The Bi-needle technique was designed to improve the efficiency and safety of PELD.

METHOD

Bi-needle and TESSYS group within each cohort were balanced using 1:1 propensity score matching. Finally, 32 patients with IDC treated by Bi-needle technique from December 2015 to September 2017 were enrolled and 25 patients treated by TESSYS technique from the same spine surgery center between January 2013 and October 2017 were enrolled as controls.

RESULTS

Propensity score matching generated 22 Bi-needle and 22 TESSYS patients. There were no significant differences in visual analog scale and lumbar Japanese Orthopaedic Association scores between Bi-needle and TESSYS group. Operative time and rate of complications in the Bi-needle was significantly better than the TESSYS group (p < 0.01).

CONCLUSIONS

Both surgical methods achieved good clinical outcomes. However, compared with the TESSSY technique, operative time of the Bi-needle technique is shorter, and rate of complications is lower.

Learning Curve and Early Results of Interlaminar and Transforaminal Full-Endoscopic Resection of Lumbar Disc Herniations

Background

Full-endoscopic spinal surgery is an evolving technique. A laborious learning phase is inevitable due to the complexity of the orientation and instrumentation. The goal of the present study is to evaluate a single surgeon’s learning curve and early outcomes in full-endoscopic resection of lumbar disc herniations.

Methods

This was a prospective non-controlled single-surgeon cohort study. In 54 patients with 57 herniations, 41 interlaminar and 16 transforaminal resections were performed. Surgery time, severity of adhesive process in the spinal canal, complication rates and clinical outcomes (VAS, ODI, custom questionnaire, recurrence and re-operation rate) were assessed.

Results

In the interlaminar group, operative time has decreased from 60 ± 20 min in the first 20 operations to 45 ± 14 min in the following 17 (p=0.023). In the transforaminal group, operative time has decreased from 60 ± 16 min in the first 7 operations to 41 ± 12 min in following 9 (p=0.023). Severe adhesive process in spinal canal was associated with duration of symptoms greater than 2 years, longer surgery and higher risk of surgical complications. Four recurrent disc herniations were re-operated using full-endoscopic technique. VAS, ODI and pain medications significantly decreased in both groups and in re-operated patients.

Conclusion

The plateau of the learning curve and good short-term clinical results of full-endoscopic interlaminar and transforaminal surgery may be achieved after twenty operations, given extensive previous experience in microsurgery. Risk of complications at the learning phase may be decreased by excluding the patients with symptoms lasting over two years.

[Effect of Quantitative indicators of ilium height on approach of percutaneous endoscopic lumbar discectomy treatment in patients with L 5, S 1 lumbar disc herniation]

Objective

To identify effect of quantitative indicators of ilium height on approach of percutaneous endoscopic lumbar discectomy (PELD) treatment in patients with L ₅, S ₁ lumbar disc herniation.

Methods

A retrospective study between May 2014 and March 2016 was conducted, including 100 patients with disc herniation at L ₅, S ₁, who were initially enrolled for the PELD treatment. Among them, 66 patients were successfully treated with PELD (group A), and the other 34 patients failed to perform puncture, catheterization, or microscopical operation due to the influence of iliac bone and other peripheral bone structures and treated with alternative surgical plans. By analyzing the X-ray films of lumbar vertebrae (including bilateral ilium) of the two groups before operation, the concept of ilium height rate and ilium angle rate was put forward innovatively. The ilium height rate and ilium angle rate of the two groups were measured and compared, and the diagnostic critical points of ilium height rate and ilium angle rate were determined by ROC curve analysis.

Results

The ilium height rate was 0.61±0.09, 0.74±0.05 and the ilium angle rate was 0.66±0.08, 0.80±0.08 in groups A and B, respectively, showing significant differences between the two groups ( F=69.729, P=0.000; F=65.165, P=0.000). ROC curve analysis showed that the critical point of ilium height rate was 0.71 (area under ROC curve was 0.927, P=0.000), and the critical point of ilium angle rate was 0.75 (area under ROC curve was 0.965, P=0.000).

Conclusion

PELD is not recommended for patients with L ₅, S ₁ intervertebral disc herniation, when the ilium height rate is greater than 0.71 and/or the ilium angle rate is greater than 0.75. Other surgical plans such as transpedicular approach, transpedicular approach, or open surgery, should be recommended to reduce the risk of surgery and the pain of patients.

The influence of gender on postoperative PROMIS physical function outcomes following minimally invasive transforaminal lumbar interbody fusion

PURPOSE

Our aim is to examine the gender performance of Patient-Reported Outcome Measurement Information System Physical Function (PROMIS-PF) scores among patients undergoing minimally invasive transforaminal lumbar fusion (MIS TLIF).

METHODS

A prospectively collected surgical dataset was retrospectively assessed for eligible patients from March 2015-June 2019. We included patients if they underwent primary MIS TLIF procedures on one or two vertebral levels. We collected baseline demographics, perioperative characteristics, and PROMIS-PF scores for each subject at pre and postoperative timepoints (e.g., 6-weeks, 3-months, 6-months, and 1-year). Chi-squared analyses were utilized to assess categorical variables and a Student's t-tests analyzed continuous variables. A linear regression was used to analyze PROMIS-PF scores from baseline through all postoperative time points. Finally, we evaluated the PROMIS PF achievement of minimal clinically important difference (MCID) among gender.

RESULTS

192 patients were included: 77 were females and 115 were males. No significant differences were observed among gender subgroups for PROMIS-PF scores at pre- or postoperative evaluations. Compared to males, females experienced significantly greater postoperative improvement with PROMIS-PF scores at the 3-month assessments, though no significant gender differences were observed during later follow-up evaluations at 6-months or one year. Females were observed to have significant PROMIS-PF score improvement from their preoperative evaluation to each postoperative score. Males were assessed to have statistically significant postoperative (e.g., at 3-months, 6-months, and 1-year) PROMIS-PF score improvement from their preoperative PROMIS-PF scores. There were no significant differences among gender in achieving MCID at any postoperative time interval.

CONCLUSION

Among gender, we observed no statistically significant difference in PROMIS-PF scores during the pre- or postoperative evaluations. Additionally, with no difference in the rate of achieving PROMIS-PF MCID postoperatively, this study established that both genders should experience similar functional outcomes following MIS TLIF.

Sex Differences on Postoperative Pain and Disability Following Minimally Invasive Lumbar Discectomy

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To determine if sex is associated with differences in postoperative pain scores, narcotic consumption, and long-term improvements in pain and disability following minimally invasive lumbar discectomy (MIS LD).

SUMMARY OF BACKGROUND DATA

There exists a question as to what extent sex influences surgical and clinical outcomes following MIS LD.

METHODS

Patients undergoing primary, single-level MIS LD were retrospectively reviewed and stratified on the basis of sex. Immediate postoperative Visual Analog Scale (VAS) pain scores and narcotic consumption were collected. Patient-reported outcomes, including Oswestry Disability Index (ODI), 12-Item Short-Form- (SF-12) Physical Component Score, and VAS back and leg pain, were collected preoperatively and at 6-week, 3-month, 6-month, and 12-month follow-up. Sex differences were tested for an association between immediate postoperative pain, narcotics utilization, and long-term improvements in patient-reported outcomes using linear regression.

RESULTS

A total of 188 patients were included and 62.8% were male individuals. At the time of surgery, female individuals were older than male individuals (P=0.045). There were no observed differences in other demographic or perioperative characteristics between cohorts. Female individuals had similar inpatient VAS pain scores and narcotic consumption compared with male individuals. Female individuals had a higher ODI score than male individuals preoperatively, however, both cohorts had similar improvements in ODI at all postoperative time points. Both sexes had similar VAS back and leg pain and SF-12 PCS scores preoperatively and at all postoperative time points.

CONCLUSIONS

Our study demonstrated that sex does not affect immediate postoperative pain, narcotic consumption, and long-term recovery following MIS LD. Female individuals demonstrated similar preoperative back and pain scores compared with male individuals but reported greater disability before surgery. However, both sexes experienced similar improvements in pain and disability at all follow-up time points through 12 months. The results of this study may enable providers to better counsel patients regarding the expected improvement in pain and disability.

Removal of calcified lumbar disc herniation with endoscopic-matched ultrasonic osteotome - Our preliminary experience

Objective: To evaluate the clinical efficacy, practicability, and safety of an ultrasonic osteotome for percutaneous transforaminal endoscopic discectomy (PTED) in patients with calcified lumbar disc herniation (CLDH).Methods: A total of 25 CLDH patients who underwent PTED at our department between December 2017 and August 2018 were analyzed retrospectively. Post-operative lumbar spine CT was used to evaluate residual calcification. Efficacy was evaluated by pre- and post-operative with the pain visual analog scale (VAS), Oswestry disability index (ODI), and the Modified MacNab Scale; the incidence of intra- and postoperative complications was also analyzed.Results: All procedures were successfully completed and none of the patients was lost to follow-up. Postoperative CT verified the successful removal of calcified protrusions. VAS and ODI scores improved significantly after surgery. Based on the Modified MacNab scale, >90% patients achieved good or excellent outcomes. There were no complications such as dural tear and infection. Seven patients had varying degrees of postoperative dysesthesia. One patient experienced recurrence of herniation within 1 week after operation; successful recovery was achieved after repeat PTED.Conclusions: Use of this ultrasonic osteotome for PTED facilitated effective removal of calcified disc protrusion, relieved nerve compression, and protected the adjacent neurovascular tissues. The instrument may help expand the indications for endoscopic surgery and avoid open surgery for some CLDH patients.

Outcomes of endoscopic discectomy compared with open microdiscectomy and tubular microdiscectomy for lumbar disc herniations: a meta-analysis

OBJECTIVE

Endoscopic discectomy (ED) has been advocated as a less-invasive alternative to open microdiscectomy (OM) and tubular microdiscectomy (TM) for lumbar disc herniations, with the potential to decrease postoperative pain and shorten recovery times. Large-scale, objective comparisons of outcomes between ED, OM, and TM, however, are lacking. The authors' objective in this study was to conduct a meta-analysis comparing outcomes of ED, OM, and TM.

METHODS

The PubMed database was searched for articles published as of February 1, 2019, for comparative studies reporting outcomes of some combination of ED, OM, and TM. A meta-analysis of outcome parameters was performed assuming random effects.

RESULTS

Twenty-six studies describing the outcomes of 2577 patients were included. Estimated blood loss was significantly higher with OM than with both TM (p = 0.01) and ED (p < 0.00001). Length of stay was significantly longer with OM than with ED (p < 0.00001). Return to work time was significantly longer in OM than with ED (p = 0.001). Postoperative leg (p = 0.02) and back (p = 0.01) VAS scores, and Oswestry Disability Index scores (p = 0.006) at latest follow-up were significantly higher for OM than for ED. Serum creatine phosphokinase (p = 0.02) and C-reactive protein (p < 0.00001) levels on postoperative day 1 were significantly higher with OM than with ED.

CONCLUSIONS

Outcomes of TM and OM for lumbar disc herniations are largely equivalent. While this analysis demonstrated that several clinical variables were significantly improved in patients undergoing ED when compared with OM, the magnitude of many of these differences was small and of uncertain clinical relevance, and several of the included studies were retrospective and subject to a high risk of bias. Further high-quality prospective studies are needed before definitive conclusions can be drawn regarding the comparative efficacy of the various surgical treatments for lumbar disc herniations.

Current techniques of endoscopic decompression in spine surgery

Endoscopic spine surgery has become a practical, minimally invasive technique for decompression in patients with spinal disc herniation or stenosis. This review aimed to summarize the current techniques of endoscopic decompression technique in spine surgery and to discuss the benefits, limitations, and future perspectives of this minimally invasive technique. Endoscopic spine decompression surgery can be categorized according to the endoscopic property: percutaneous endoscopic (full-endoscopic), microendoscopic, and biportal endoscopic. It can also be classified based on the approach: transforaminal, interlaminar, anterior, posterior, and caudal approaches. Theoretically, each technique can be applied in the lumbar, cervical, and thoracic spine. The various endoscopic spine surgery techniques should be appropriately conducted according to the disease entities, level, and zone of pathologies. Although the current level of evidence is relatively low and the relevance of the technique is controversial, recent clinical results and the critical concept are promising. Development in optics, instruments, and approach will improve its safety and reduce technical complexity. In the meantime, high-quality clinical studies, including randomized trials and meta-analyses, are due for publication. Eventually, endoscopic spine surgery is expected to become the golden standard for spinal surgery.

Treatment of L5 - S1 intervertebral disc herniation with posterior percutaneous full-endoscopic discectomy by grafting tubes at various positions via an interlaminar approach

Background

Depending on the location of the herniated disc at the shoulder, axilla, or ventral side of the compression nerve root, various puncture sites and channel entrances were selected so that the goal of targeted removal of the herniated disc could be achieved by a full-endoscopic technique. Achieving good clinical therapeutic efficacy through the natural gap of bones can maximally avoid related access complications, and the necessary techniques and relevant anatomical factors were analyzed.

Methods

Between August 2012 and August 2014, 98 patients with L5 - S1 intervertebral disc herniation were treated with posterior percutaneous full-endoscopic discectomy (PPFED) by grafting tubes at various positions via the interlaminar approach. The visual analog scale (VAS) and the Oswestry disability index (ODI) were used to assess the patients’ back and leg pain and the improvements in daily function, and the modified Macnab standard was used to evaluate the treatment efficacy.

Results

All 98 patients successfully completed the surgery, 84 patients got out of bed and walked on the first postoperative day, and 14 patients got out of bed and walked on the second postoperative day. The preoperative ODI (56.032 ± 3.625) was significantly higher than the ODI score (8.147 ± 1.398) (F = 5343.054, P ≤ 0.001) 48 months after surgery. The preoperative VAS score (7.193 ± 0.875) was significantly higher than the postoperative VAS score (0.914 ± 0.500 points) (F = 1656.173, P ≤ 0.001). The differences in ODI and VAS scores before and after surgery were statistically significant (P < 0.05). Follow-up was conducted 1, 6, 12 and 48 months postoperatively, and the modified Macnab standard was used during the last follow-up to evaluate the efficacy: 67 cases were excellent, 20 cases were good, 7 cases were fair, and 0 cases were poor; the proportion of excellent and good cases was 92.6%.

Conclusions

The treatment of L5 - S1 intervertebral disc herniation with PPFED by grafting tubes at various positions via an interlaminar approach is a safe, effective, and minimally invasive surgical method. Reaching the location of a disc herniation directly through the natural gap in the bones can maximally avoid collateral injury from spine surgery.

Trial registration

The registration number of this clinical study is ChiCTR1800014588; it has been retrospectively registered with a registration date of 05/01/2018.

Endoscopic transforaminal lumbar interbody fusion: a comprehensive review

INTRODUCTION

Endoscopic spine surgery has been developed as a minimally invasive technique for decompression in patients with lumbar disc herniation or lumbar stenosis. Recent reports have described the use of endoscopic technology in lumbar fusion surgeries, especially for transforaminal lumbar interbody fusion (TLIF). This review aimed to summarize the current techniques of endoscopic TLIF and to discuss the benefits, limitations, and future perspectives of endoscopic lumbar fusion surgery.

AREAS COVERED

This review covered the English-language medical literature published in Medline and focused specifically on endoscopic technologies incorporated into minimally invasive TLIF. The endoscopic TLIF techniques are categorized here according to the properties of the endoscope: percutaneous endoscopic TLIF, biportal endoscopic TLIF, and microendoscopic TLIF. Even though most authors have reported favorable clinical and radiological outcomes of endoscopic TLIF, such evidence originates mainly from case series.

EXPERT OPINION

Although the current level of evidence is low and the technical relevance of the technique is controversial, the key concept and early results of endoscopic TLIF are promising. Technical advancements to improve safety and reduce technical complexity, as well as comparative cohort studies and randomized clinical trials with long-term follow-up are required to promote the adoption of endoscopic TLIF in clinical practice.