Percutaneous endoscopic lumbar discectomy for migrated disc herniation: classification of disc migration and surgical approaches

Reliability Analysis of Deep Learning Algorithms for Reporting of Routine Lumbar MRI Scans

BACKGROUND

Artificial intelligence could provide more accurate magnetic resonance imaging (MRI) predictors of successful clinical outcomes in targeted spine care.

OBJECTIVE

To analyze the level of agreement between lumbar MRI reports created by a deep learning neural network (RadBot) and the radiologists' MRI reading.

METHODS

The compressive pathology definitions were extracted from the radiologist lumbar MRI reports from 65 patients with a total of 383 levels for the central canal: (0) no disc bulge/protrusion/canal stenosis, (1) disc bulge without canal stenosis, (2) disc bulge resulting in canal stenosis, and (3) disc herniation/protrusion/extrusion resulting in canal stenosis. For both, neural foramina were assessed with either (0) neural foraminal stenosis absent or (1) neural foramina stenosis present. Reporting criteria for the pathologies at each disc level and, when available, the grading of severity were extracted, and the Natural Language Processing model was used to generate a verbal and written report. The RadBot report was analyzed similarly as the MRI report by the radiologist. MRI reports were investigated by dichotomizing the data into 2 categories: normal and stenosis. The quality of the RadBot test was assessed by determining its sensitivity, specificity, and positive and negative predictive value as well as its reliability with the calculation of the Cronbach alpha and Cohen kappa using the radiologist MRI report as a gold standard.

RESULTS

The authors found a RadBot sensitivity of 73.3%, a specificity of 88.4%, a positive predictive value of 80.3%, and a negative predictive value of 83.7%. The reliability analysis revealed the Cronbach alpha as 0.772. The highest individual values of the Cronbach alpha were 0.629 and 0.681 when compared to the MRI report by the radiologist, rending values of 0.566 and 0.688, respectively. Analysis of interobserver reliability rendered an overall kappa for the RadBot of 0.627. Analysis of receiver operating characteristics (ROC) showed a value of 0.808 for the area under the ROC curve.

CONCLUSIONS

Deep learning algorithms, when used for routine reporting in lumbar spine MRI, showed excellent quality as a diagnostic test that can distinguish the presence of neural element compression (stenosis) at a statistically significant level (P < .0001) from a random event distribution. This research should be extended to validated and directly visualized pain generators to improve the accuracy and prognostic value of the routine lumbar MRI scan for favorable clinical outcomes with intervention and surgery.

LEVEL OF EVIDENCE

3.

CLINICAL RELEVANCE

Validity, clinical teaching, and evaluation study.

Endoscopic Transforaminal Lumbar Interbody Fusion With a Single Oblique PEEK Cage and Posterior Supplemental Fixation

BACKGROUND

To demonstrate the feasibility of an endoscopically assisted minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF) and to study clinical outcomes with the use of a static oblique bullet-shaped cannulated poly-ether-ether-ketone (PEEK) lumbar interbody fusion cage in conjunction with platelet enriched plasma infused allograft cancellous chips and posterior supplemental fixation.

METHODS

In this retrospective study of 43 patients who underwent endoscopically assisted MIS-TLIF for spondylolisthesis (53.5%) and stenosis (46.3%), the Oswestry Disability Index, the visual analog scale (VAS) for back and leg pain, and the modified Macnab criteria were used as primary clinical outcome measures. Clinical outcomes were cross-tabulated against fusion grade using the Bridwell classification of interbody fusion.

RESULTS

The majority of patients (90.7%) had excellent (8/43; 18.6%) and good (31/43; 72.1%) Macnab outcomes. There were significant VAS back score reductions from an average preoperative values of 8.9070 to a postoperative VAS score of 3.8605, and a score of 2.7674 at final follow-up (P < .0001). The reductions in the VAS leg scores were also significant from preoperative score of 5.58 to a postoperative value of 2.16, and a final follow-up score of 1.67 (P < .0001); the Oswestry Disability Index score went from a preoperative value of 54.4 to 23.3 postoperatively and 18.5 at the final follow-up (P < .0001). The vast majority of patients (92.9%) with Bridwell grade I fusion had excellent and good Macnab outcomes (P = .027).

CONCLUSIONS

The authors recommend the use of an endoscope as an adjunct to MIS-TLIF, a minimally invasive spinal surgery technique in which many surgeons may be well versed and have a great deal of experience. Clinical outcomes with the endoscopic interbody fusion procedure with a static PEEK cage in conjunction with platelet-enriched bone allograft were favorable.

LEVEL OF EVIDENCE

3.

CLINICAL RELEVANCE

Feasibility study.

Early Clinical Outcomes of Percutaneous Endoscopic Lumbar Discectomy for L4-5 Highly Down-Migrated Disc Herniation: Interlaminar Approach Versus Transforaminal Approach

OBJECTIVE

This study is a retrospective evaluation of patients with L4-5 highly down-migrated lumbar disc herniation (LDH) operated with interlaminar endoscopic lumbar discectomy (IELD) versus transforaminal endoscopic lumbar discectomy (TELD).

METHODS

From January 2015 to December 2018, 77 patients with L4-5 highly down-migrated LDH were divided into 2 groups according to different surgical approaches. There were 40 patients who underwent IELD, and 37 patients who underwent TELD. The operation time, hospital stay, Oswestry Disability Index, clinical outcome according with modified MacNab criteria, Visual Analog Scale (VAS) scores, and complications were compared between the IELD and TELD groups.

RESULTS

Seventy-seven patients were included, 40 and 37 patients underwent IELD and TELD, respectively. The IELD and TELD groups both achieved a significant improvement in Oswestry Disability Index, back and leg VAS scores, and clinical outcome postoperation. Mean operating and x-ray times during operation were significantly shorter in the IELD group than in the TELD group (41.8 vs. 50.3, 1.8 vs. 13.7). There were 3 patients who experienced recurrence in the IELD group and 2 in the TELD group. In the TELD group, there were 3 patients who required revision surgery due to incompletely removed disc fragment. All patients in the IELD group were treated successfully. There was no other complication in these cases.

CONCLUSIONS

Both IELD and TELD could be a good alternative option for highly down-migrated LDH in L4-L5. IELD may have advantages in operation time and x-ray times during operation compared with TELD.

Laser Therapy in Lumbar Disc Surgery - A Narrative Review

Introduction: Low back pain is one of the most chronic debilitating conditions involving considerable loss of cash, work, and quality time. Lasers are utilized in different fields of drugs, providing unique advantages. They are useful and advantageous in treating lumbar disc disease. In this research, an attempt is made to examine the role and importance of different lasers in lumbar disc surgeries. Methods: We conducted studies about laser therapy in lumbar disc surgery. Our primary search began with reviewing English-language citations from PubMed and Scopus between 1990 and 2019 using the keywords: (laser therapy) OR (lumbar disc AND disc surgery). The initial search yielded 97 articles. However, about 49 articles were selected and used in the present study. Results: Based on the present study, it can be found that there are several methods of using lasers to treat lumbar disc surgery. These methods all have their strengths and weaknesses. Conclusion: The development of laser lumbar disc surgery can be very helpful due to the reduction of surgical risks and the length of the patients' hospital stay. However, the choice of method used for this type of surgery should be made according to the patient's condition and based on the opinion of the treating physician.

Clinical Anatomy and Possible Clinical Significance of the Postcentral Branches of Spinal Arteries in the L1-L5 Levels

STUDY DESIGN

This was a dissection-based study of 10 embalmed human cadavers.

OBJECTIVE

The objective of this study was to identify and describe the postcentral branches in the L1-L5 intervertebral foramina (IVF) and to determine their possible clinical significance.

SUMMARY OF BACKGROUND DATA

The lower lumbar segmental arteries have been well studied. However, there are few articles with regard to the postcentral branches in the L1-L5 IVF.

MATERIALS AND METHODS

Eighty L1-L5 IVF from 10 embalmed cadavers were studied with a surgical microscope, and the postcentral branches were identified. The branches, origin, insertion, and spatial orientation of the postcentral branches in the L1-L5 IVF were examined. The diameter of the arteries was measured using a Vernier caliper.

RESULTS

In our study, the occurrence rate of a postcentral branch was 100.00% in the 80 IVFs. The postcentral branch was routinely divided into the following 2 types: type 1, postcentral branch main trunks (65.00%), which branch from the spinal arteries or lumbar arteries and then divide into 2 branches (superior and inferior branches), and type 2, superior and inferior branches, which branch straight from the spinal arteries (35.00%). The initial portion of the postcentral branches traveled around the anterolateral edge of the disk to the dorsum.

CONCLUSIONS

Postcentral branches of spinal arteries are common structures in IVF; there are 2 types of postcentral branches. Thorough understanding of the spinal arteries before percutaneous endoscopic lumbar discectomy may be an important step in reducing intraoperative bleeding and ensuring clear visualization, which may result in significant benefits for patients.

Necessity of routinely performing foraminoplasty during percutaneous endoscopic transforaminal discectomy (PETD) for lumbar disc herniation

OBJECTIVE

To assess the role of foraminoplasty during percutaneous endoscopic transforaminal discectomy (PETD) and compared the 2-year clinical results of patients underwent PETD w/o foraminoplasty.

METHODS

A total of 412 patients, who underwent PETD at L3-S1 by the same surgical group, were enrolled in this study. The MRI was used to determine the height (H1) and width (W1) of the intervertebral foramen of L3-S1, the distance between the exiting nerve root and the upper edge of the lower vertebral pedicle (H2), and the distance (W2) between the point with 3 mm to the ventral side of the intervertebral space and superior articular process. The intervertebral foramen widths in the flexion (W3) and extension positions (W4) were also measured. A VAS of low back pain (LBP) and leg pain, ODI and JOA scores of LBP were used to assess the clinical results.

RESULTS

Intraoperative verification showed that 347 cases (group A) did not need foraminoplasty, while the other 65 patients (group B) needed foraminoplasty, including 31 at L4-5 and 34 at L5-S1. The H1 and H2 of L3-S1 were reduced gradually without significant difference between two groups. The W1, W2, W3 and W4 were higher in group A (p < 0.05). The W3 was higher than W4 in both groups (p < 0.05). At 2-year follow-up, there was no significant difference of ODI and JOA score between two groups (p > 0.05). The VAS score of LBP was better in group A (p < 0.05).

CONCLUSIONS

Most of PETD procedure at L3-S1 levels could reach the therapeutic target without foraminoplasty. Due to anatomic characteristics of L5-S1, the foraminoplasty rate was much higher at L5-S1.

Technical Considerations of the Transforaminal Approach for Lumbar Disk Herniation

Transforaminal full endoscopic lumbar diskectomy (TELD) is a typical minimally invasive surgery, with the associated benefit of decreased possibility of anatomic structural injury, and is an effective alternative to open diskectomy. Among the various endoscopic spinal surgical techniques currently available, TELD is the most basic and traditional surgery that can be performed through the transforaminal route; it has been used for >30 years. Recently, with the advancements in surgical techniques, TELD has been successfully performed for patients with lumbar disk herniation of different types. However, beginner surgeons are unfamiliar with the anatomy of transforaminal endoscopic surgery and this surgery has a steep learning curve to date. If not well prepared, operators may experience complications that require reoperation in the early stages. These complications may include symptomatic incomplete decompression, exiting nerve root injury, dural tearing, and rarely, hematoma, infection, and visceral injury. Here, we propose several technical guidelines for TELD to increase the possibility of successful lumbar diskectomy and to reduce the incidence of complications. The first step is the accurate anatomic understanding of Kambin triangle and determining the appropriate endoscopic access angle, depending on the type of disk herniation. The second step is to determine a safe and easily accessible entry point and then landing and docking the working sleeve as close to the target as possible without causing exiting nerve root injury. The third step is complete decompression of the symptomatic nerve with free mobilization of the neural tissue. The final step involves performing foraminoplasty using an advanced technique to overcome the limitations associated with TELD in difficult cases.

The Evolution of Transforaminal Endoscopic Spine Surgery

Transforaminal endoscopic spine surgery (T-ESS) has become a well-accepted technique. The first attempts at percutaneous discectomy by Kambin and Hijikata opened a new chapter of endoscopic spine surgery. By the last quarter of the twentieth century, spine surgeons had begun to adopt this novel technique. Many researchers helped advance endoscopic spine surgery, but the turning point was the description of a safe transforaminal triangle of safety by Parviz Kambin. Since then, the indications for T-ESS have increased as a result of the description of different surgical approaches such as inside-out, outside-in, and half-and-half. We present a review of crucial historical advancements in T-ESS and also discuss the evolution of endoscopes, the techniques used, development of endoscopic instruments and equipment, transforaminal thoracic endoscopy, transforaminal endoscopic interbody fusions, the growth of extended indications, and the future direction of T-ESS. This review provides a detailed description of key historical moments and a bird's-eye view of the vast scope of T-ESS.

Suprapedicular Retrocorporeal Technique of Transforaminal Full-Endoscopic Lumbar Discectomy for Highly Downward-Migrated Disc Herniation

OBJECTIVE

Anatomical barriers (e.g., pedicles, narrow foramina) can hinder direct access to, and removal of, disc fragments that have migrated far downward. Using transforaminal full-endoscopic lumbar discectomy (FELD), we devised a modified technique, the suprapedicular retrocorporeal approach, for herniations in which the disc has migrated to the axilla of the traversing nerve roots. In the present report, we have described our preliminary results.

METHODS

Soft, highly downward-migrated disc herniation was treated with transforaminal FELD through the suprapedicular retrocorporeal approach in 22 patients from June 2017 to May 2019. The clinical outcomes were evaluated, including the preoperative and postoperative visual analog scale scores for the back and leg, Oswestry disability index, and MacNab criteria for surgical success.

RESULTS

The affected discs were at L4-L5 in 14 patients, L3-L4 in 6 patients, and L5-S1 in 2 patients. In each case, the affected disc was successfully removed using the suprapedicular retrocorporeal approach. The mean follow-up was 18.1 ± 5.7 months. The mean visual analog scale scores for back and leg pain improved significantly (P < 0.05 for both). The mean Oswestry disability index had decreased from 62.5 ± 14.2 preoperatively to 10.5 ± 5.9 postoperatively (P < 0.05). Using the MacNab criteria, 13 patients reported excellent outcomes and 9, good outcomes. No complications or recurrence developed during follow-up.

CONCLUSIONS

The suprapedicular retrocorporeal technique is a feasible and effective surgical option in transforaminal FELD for the treatment of herniation in which the disc has migrated to the axilla of the traversing nerve roots.

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.

Modified Interlaminar Endoscopic Lumbar Discectomy for Highly Upmigrated Disc Herniation: A Proctorship Description of the Technique via Translaminar Route

Lumbar disc herniation (LDH) comprises one of the most common causes of low back pain. 35%–72% of LDH is associated with disc fragment migration. The migration of the disc fragments can be high-grade up, low-grade up, high-grade down, and low-grade down. Spine surgeons deal with unique challenges during surgical management of migrated discs. Operational challenges with open surgery include extensive lamina excision, pars excision, and potential for iatrogenic instability without fixation. In contrast, rigid instruments and poor visualization are the challenges with transforaminal endoscopic spine surgery (ESS). Hence interlaminar approach with ESS is an excellent choice with these migrated LDH. The creation of a translaminar crater in the cranial lamina without dealing with the interlaminar window or ligamentum flavum could be an excellent option to deal with these herniations face front. The lamina is the only anatomical barrier between the endoscope and the migrated disc fragment. Hence with a translaminar approach, unnecessary flavectomy can be avoided. In this technical report and video, we demonstrate the surgical technique of performing the translaminar ESS for highly upmigrated LDH with the preservation of optimal natural anatomy.

A Novel Foraminoplasty Technique for Posterolateral Percutaneous Transforaminal Endoscopic Lumbar Surgery

BACKGROUND

In posterolateral percutaneous transforaminal endoscopic lumbar surgery, foraminoplasty is currently performed by resecting part of the superior articular process together with surrounding soft tissues. This procedure remains technically demanding. An ideal foraminoplasty technique should be safe, easy, efficient, and controllable and should minimize X-ray exposure.

OBJECTIVE

To introduce a novel foraminoplasty technique that is designed in an attempt to obtain the ideal state.

METHODS

The technique is introduced step by step by case illustration. Briefly, the technique is based on the addition of a novel instrument, named a "Foraminoplasty Working Tube," to the commercialized spinal endoscope system. Through the foraminoplasty working tube, the foraminoplasty procedure can be performed under either reduced X-ray guidance or direct endoscopic view.

RESULTS

The technique allows the surgeon to perform an accurate resection of the superior articular process by easily adjusting the foraminoplasty working tube to the target area. To a great extent, the volume of the bone resected is predictable and controllable and just meets the demands of the operation without excessive resection of the superior articular process.

CONCLUSION

The present technique would potentially be a safer, easier, and more efficient foraminoplasty technique.

Fully Endoscopic Transforaminal Lumbar Discectomy for Upward Migration of Upper Lumbar Disc Herniation: Clinical and Radiological Outcomes and Technical Considerations

Microdiscectomy for the upward migration of upper lumbar herniated discs has a high risk of isthmus and facet injury. Fully endoscopic transforaminal discectomy can preserve normal bony structures during discectomy. The purpose of this study was to assess the clinical and radiological outcomes of fully endoscopic transforaminal discectomy for upward migrated upper lumbar herniated discs. All patients had upward migrated disc herniation from L1–L2 to L3–L4 levels and were treated using fully endoscopic transforaminal discectomy under local anesthesia. All enrolled patients were monitored for more than 12 months. Clinical outcomes were assessed using the Oswestry Disability Index (ODI) and visual analog scale (VAS) of pain. Surgery-related complications were analyzed. In addition, radiological outcomes were investigated using postoperative magnetic resonance imaging (MRI) and lumbar dynamic X-ray. Twenty-eight patients were enrolled in this study. ODI and VAS significantly decreased after endoscopic transforaminal discectomy. Migrated ruptured disc particles were completely removed and confirmed on postoperative MRI in 26 of the 28 patients. Even though small remnant disc particles were detected in two patients, symptoms improved after endoscopic transforaminal discectomy. Early recurrence of herniated disc occurred at the operated segment in one patient. There were no significant complications associated with fully endoscopic transforaminal discectomy. Three patients experienced a postoperative transient tingling sensation and numbness of the leg. Fully endoscopic transforaminal lumbar discectomy may be an effective and alternative treatment option for upward migrated disc herniation in the upper lumbar area. In addition, fully endoscopic transforaminal lumbar discectomy may prevent complications associated with general endotracheal anesthesia and injuries of the isthmus and the facet joint.

Percutaneous Endoscopic Lumbar Discectomy (PELD) via a Transforaminal and Interlaminar Combined Approach for Very Highly Migrated Lumbar Disc Herniation (LDH) Between L4/5 and L5/S1 Level

Background

Percutaneous endoscopic lumbar discectomy (PELD) has become one of the most popular minimally invasive surgeries for lumbar disc herniation (LDH), however, very highly migrated LDH is still a tricky issue for PELD. This study reported a new endoscopic discectomy strategy for the treatment of very highly migrated LDH between the L4/5 and L5/S1 level.

Material/Methods

The current study retrospectively analyzed 12 patients who accepted PELD for very highly migrated LDH between the L4/5 and L5/S1 level. Under local anesthesia, the transforaminal approach was chosen for the L4/5 level and the interlaminar approach was chosen for the L5/S1 level. The 10-point visual analogue scale (VAS) was used to assess back pain (VAS-Back) and leg pain (VAS-Leg). Oswestry disability index (ODI) and Modified Mac Nab Criteria were adopted as the functional evaluation methods. All patients were followed in the outpatient department for at least 12 months after their operation.

Results

Our study showed that very highly migrated disc between L4/5 and L5/S1 level could be removed completely by this strategy. Except for 1 case of postoperative dysesthesia and 1 case of dural tear, no severe complication occurred. At the last follow-up, the average VAS-Back score of the study patients was reduced from 5.17±2.12 to 2.08±1.08 (P<0.05) and the average VAS-Leg score was reduced from 7.25±1.48 to 1.33±0.89 (P<0.05). The average ODI scores improved from 48.50±10.59 to 13.00±2.76 (P<0.05). According to the Modified Mac Nab Criteria, 83.33% of patients (10 out of 12 patients) received an excellent or good recovery and no poor result was reported. No recurrence was observed during follow up.

Conclusions

PELD via a transforaminal and interlaminar combined approach provides an alternative option for select patients with very highly migrated LDH between the L4/5 and L5/S1 level.

The evolution of interlaminar endoscopic spine surgery

Due to the aging population, patients required spinal surgery for degenerative spondylopathy is increasing. With the advent of surgical instruments and techniques, minimally invasive spine surgery is prevalent worldwide. Besides microscopic techniques, endoscopic spine surgery has gotten attention gradually in this surgical field for the past two decades. There are two essential approaches developed currently, including transforaminal and interlaminar approach. These innovative equipment and skills promote the progression of endoscopic surgery from discectomy to decompression of spinal stenosis. Meanwhile, they also opened up the application of endoscopic surgery in a complicated situation. From the perspective of emerging technologies and techniques, the authors will review the evolution and describe the prospects of the interlaminar endoscopic spine surgery (IESS).

Evolution of endoscopic transforaminal lumbar approach for degenerative lumbar disease

Endoscopic spine surgery has evolved dramatically in last 30 years; with the development of new improved endoscopic optics and instrumentation limitation of endoscopic spine surgery has significantly reduced. The transforaminal approach has been limited in its indications due to its optimized approach and obstacles of bony or neural structures. As the initial transforaminal approach is based on the inside out technique, there were many limitations on the indications. Outside-in approach has been developed to address these limitations. However, the outside-in approach was not free from anatomical obstacles. The mobile outside-in approach technique has advantage of both inside-out and outside-in technique. It is equally safe as inside-out technique and provides an easy handling of structures, while it is equally versatile as outside-in technique in managing different types of disc prolapse such as central, paracentral, foraminal, far lateral, and up and down migration, and in high-canal compromise cases. The mobile outside in technique, however, demands a longer learning curve and beginners need to be patient while learning the technique.

Biportal endoscopic discectomy for high-grade migrated lumbar disc herniation

OBJECTIVE

Although endoscopic procedures for lumbar disc herniation have improved greatly and offer many advantages, the indications are limited mostly to nonmigrated or low-grade migrated disc herniation. Endoscopic application in migrated disc herniation cases is still challenging and technically demanding. The goal in this study was to determine the feasibility of biportal endoscopic discectomy for removal of high-grade migrated disc herniation.

METHODS

A retrospective review was performed in 262 patients who had undergone biportal endoscopic discectomy after the diagnosis of lumbar herniated disc. According to preoperative MRI findings, disc herniation was classified into 5 zones based on the direction and distance from the disc space. Patients were divided into 2 groups-a high-grade migration group and a low-grade migration group. Clinical outcomes were evaluated using the Oswestry Disability Index (ODI), visual analog scale (VAS), and modified Macnab criteria, and those outcomes and operation time were compared between the 2 groups.

RESULTS

There were 10 patients with "high-grade up," 8 with "low-grade up," 98 with disc-level, 102 with "low-grade down," and 44 with "high-grade down" herniation, thereby yielding 54 patients in the high-grade group and 208 in the low-grade group. Demographic data for the 2 groups showed no significant difference. There was no significant difference between the 2 groups in ODI, VAS, and modified Macnab criteria. Operation time between the 2 groups was not significantly different (60.74 vs 65.63 minutes, p > 0.05).

CONCLUSIONS

Biportal endoscopic discectomy can be effective for high-grade migrated lumbar disc herniation with no prolonged operation time and satisfactory clinical outcomes.

Residual leg numbness after endoscopic discectomy treatment of lumbar disc herniation

Background

Transforaminal endoscopic discectomy was popular in the treatment of lumbar disc herniation. Previous study focuses on the leg pain of disc herniation, and little study concern the residual leg numbness after surgery. The purposes of this study were to evaluate the clinical outcomes of transforaminal endoscopic discectomy in the treatment of lumbar disc herniation with leg pain and numbness.

Methods

Patients with one level lumbar disc herniation who had transforaminal endoscopic lumbar discectomy from June 2016 to July 2019 were categorized into two groups according to the leg numbness. 293 patients initially fulfilled the study criteria, and 27 patients were lost to follow-up. Of the remaining 266 patients available for analysis, 81 cases with leg numbness and pain (A group), and 185 cases with leg pain (B). Endoscopic transforaminal lumbar discectomy was performed, and the clinical outcomes of blood loss, operation times, hospital stay days, pain (Visual Analog Scale, VAS-pain), numbness (VAS-numbness), functional disability (Oswestry Disability Index, ODI), and the disk height and intervertebral foramen height were recorded.

Results

All patients with pain and numbness pre-operation in group A, complain of leg numbness during or just after walking or standing not diminished after surgery in group A, and no one complain numbness after surgery in group B. The pain index and ODI score were better than preoperational in all patients (P < 0.01), and no significant difference between two groups (P > 0.05). The postoperative disk and foramen height were no significant difference compare to preoperative in all patients (P > 0.05), and no significant difference between two groups (P > 0.05). The leg numbness symptoms last longer in central disc herniation patients (10.4 ± 2.2 months) than in paracentral (6.3 ± 2.1 months) and foraminal disc herniation patients (5.6 ± 2.3 months) after surgery (P < 0.01).

Conclusions

Based on the results of this study, transforaminal endoscopic lumbar discectomy was effective and safe procedures in the treatment of disc herniation with leg pain and numbness. The leg numbness symptoms last longer in central disc herniation patients than in paracentral and foraminal disc herniation patients after surgery.

Clinical Application of Percutaneous Transforaminal Endoscopic Surgery in Lumbar Discal Cyst

BACKGROUND

Discal cyst is very rare and can cause intractable low back pain and radiating leg pain. Symptoms are hard to distinguish from lumbar disc herniation. The best treatment for discal cyst is controversial. Most lumbar discal cysts are treated surgically, while most studies of percutaneous transforaminal endoscopic surgery are case reports. This study investigated the clinical value of percutaneous transforaminal endoscopic surgery for lumbar discal cyst.

METHODS

A retrospective study was conducted in 9 patients with a discal cyst from June 2016 to November 2018. All patients had been treated by percutaneous transforaminal endoscopic surgery via a superior vertebral pedicle notch approach. Surgical outcomes were evaluated preoperatively and postoperatively using a visual analog scale for leg pain and the Oswestry Disability Index. At the final follow-up, patients were evaluated for clinical efficacy using modified Macnab criteria.

RESULTS

All 9 patients had remission of symptoms after removal of discal cysts. Postoperative magnetic resonance imaging showed that all patients had complete excision of discal cysts and complete decompression of the treated segment. There were no recurrent lesions during follow-up. Mean operative time was 68.67 ± 14.02 minutes. Mean hospitalization time was 4.22 ± 1.64 days. Preoperative visual analog scale and Oswestry Disability Index score improved significantly after surgery. Visual analog scale leg score improved from 7.88 ± 1.05 preoperatively to 1.78 ± 0.66 at final follow-up (P < 0.05), and ODI score improved from 53.65 ± 12.46 to 16.25 ± 8.76 (P < 0.05). According to the modified Macnab criteria, 5 patients (55.6%) were rated excellent, 3 patients (33.3%) were rated good, and 1 patient (11.1%) was rated fair at final follow-up, with an overall excellent and good rate of 88.9%. There were no serious complications during follow-up.

CONCLUSIONS

Percutaneous transforaminal endoscopic surgery could be a safe, minimally invasive surgical treatment for discal cyst, particularly suitable for patients who cannot undergo general anesthesia.

Percutaneous Endoscopic Lumbar Discectomy Versus Microdiscectomy for the Treatment of Lumbar Disc Herniation: Pain, Disability, and Complication Rate-A Randomized Clinical Trial

Purpose

The objective was to compare the traditional microdiscectomy with percutaneous endoscopic lumbar discectomy for the treatment of disc herniations regarding pain, disability, and complications.

Methods

Randomized clinical trial with 47 patients with disc herniations treated with 2 different surgical techniques: traditional microdiscectomy or percutaneous endoscopic lumbar discectomy. Forty-seven patients were divided into 2 groups and monitored for 12 months. Irradiated and low back pain were evaluated with the visual analog scale. Surgery complications were recorded.

Results

After surgery, the sciatica and disability improved significantly but without significant differences between the groups. Improvements in back pain were significant until the third month. There were no statistical differences between groups regarding recurrence, infection, and the need for reoperation.

Conclusions

Endoscopic discectomy results are similar to those of conventional microdiscectomy regarding pain and disability improvement. Postoperative lumbar pain is less intense with endoscopic discectomy than conventional microdiscectomy only during the first 3 months. Endoscopic discectomy is a safe and efficient alternative to microdiscectomy.

Clinical Trials

Trial protocol registration number: RBR-5symrd (http://www.ensaiosclinicos.gov.br).

Full Endoscopic Technique for High-Grade Up-Migrated Lumbar Disk Herniation via a Translaminar Keyhole Approach: Preliminary Series and Technical Note

Background and Study Aims Technically and anatomically, accessing a high-grade migrated lumbar disk herniation (LDH) using traditional full endoscopic lumbar diskectomy (FELD) approaches (either transforaminal or interlaminar) is challenging. The objective of this study was to present an effective and safe surgical approach for high-grade up-migrated LDH by translaminar FELD.

Patients and Methods Thirteen patients with soft high-grade up-migrated LDH treated with a translaminar FELD between May 2015 and July 2018 were reviewed in this study. Five of these patients had very high-grade up-migration. Clinical outcomes were assessed including preoperative and postoperative visual analog scale (VAS) for back and leg pain, Oswestry Disability Index (ODI), and MacNab criteria.

Results Overall, 7 of the 13 patients had disk-fragment migration at L4–L5: three at L5–S1, two at L3–L4, and the remaining one at L2–L3. In all cases, the highly up-migrated LDH was removed successfully through the translaminar approach, as confirmed by postoperative magnetic resonance imaging. The improvements of VAS for back and leg pain were 4.5 ± 0.9 to 1.3 ± 1.3 and 7.1 ± 1.0 to 1.6 ± 0.7, respectively (both p < 0.05). The ODI decreased from preoperative 41.9 ± 6.0 to postoperative 13.0 ± 4.1 (p < 0.05). According to the MacNab criteria, the satisfaction rate was 92.3% (excellent or good outcomes). None of the patients experienced any perioperative complications or recurrence during the follow-up period.

Conclusion Although full endoscopic technique via the translaminar keyhole route may not be used as a routine surgical approach, it could serve as a feasible alternative method for patients with highly up-migrated disk herniation.

Longitudinal clinical outcomes after full-endoscopic lumbar discectomy for recurrent disc herniation after open discectomy

OBJECTIVE

Full-endoscopic lumbar discectomy (FELD) is a minimally invasive surgical option for recurrent lumbar disc herniation (LDH). Nonetheless, patients' clinical outcomes may be poorer after surgery for recurrent LDH than for primary LDH. Therefore, we compared patients' longitudinal clinical outcomes after FELD for recurrent LDH or primary LDH.

METHODS

The medical records of patients who underwent FELD for primary LDH (group A) or recurrent LDH (group B) were retrospectively reviewed. The inclusion criteria were: 1) single-level LDH or recurrent LDH at L4-5 or L5-S1, 2) age ≤60 years, 3) previous open discectomy (group B), and 4) ≥6 months of follow-up. In total, 244 patients (group A, 211; group B, 33) were included. Clinical outcomes (Oswestry Disability Index [ODI]; visual analogue pain score for the back and leg [VAS-B] and [VAS-L]) over 24 months of follow-up were compared between groups with a linear mixed-effects model.

RESULTS

All clinical outcomes significantly improved from pre-operation to 3 months postoperatively (p < 0.01), and the improvement was maintained for 24 months postoperatively in both groups. The clinical outcomes of groups A and B were not significantly different during 24 months follow-up (ODI, p = 0.94; VAS-B, p = 0.11; and VAS-L, p = 0.48). The reoperation rate was 3.3% in group A and 3.0% in group B, but the overall complication rate was higher in group B (9.8%) than in group A (6.6%).

CONCLUSION

The longitudinal clinical outcomes after FELD for recurrent LDH may not be poor as feared. However, the higher complication rate in patients undergoing FELD for recurrent LDH should be noted.

Return to work and recovery time analysis after outpatient endoscopic lumbar transforaminal decompression surgery

BACKGROUND

This study aimed to analyze the return to work (RTW) and recovery time (RT) to narcotic independence following outpatient endoscopic decompression for contained lumbar herniated disc causing sciatica-type low back and leg pain.

METHODS

A retrospective study of 442 patients with symptomatic contained lumbar herniated disc was treated with the transforaminal endoscopic decompression surgery. The mean follow-up was 33.5 months, ranging from 24 to 85 months. The patients' age ranged from 30 to 85 years, with a mean age of 40.9 years. Statistical analysis of pre- and postoperative VAS, Macnab outcomes, improvement of postoperative walking endurance was performed. RTW rates were correlated with the type of work as classified according to energy consumption per minute (Kcal/min) as Light, Medium, and Heavy using guidelines adopted from the U.S. Department of Labor. Kaplan-Meier (KM) survival tables were calculated, and curves were plotted using IBM SPSS 25.0 to graphically illustrate the diverse RTW and RT dynamic when analyzed by the clinical outcome and the type of work performed by the patient preoperatively.

RESULTS

Excellent (237/442) and Good (133/442) results were obtained in 83.7% (370/442) of patients. Fair results were reported by 43 patients (9.7%), and Poor results by 29 (6.6%), respectively. The mean preoperative VAS was 8.08. The mean postoperative VAS was significantly reduced to 2.55 (P<0.0001). The overall RTW rate was 92.5% (409/442). Patients performing Heavy (RTW rate =87.5%) and Medium (RTW rate =86.0%) work had a lower RTW rate than patients who were performing Light jobs (370/442; RTW rate =95.8%). Preoperatively, only 31.7% (140/442) had unlimited walking endurance. Postoperative walking endurance was unlimited in 77.4% (342/442; P<0.0001). Another 20.4% (90/442) of patients had pain-free walking endurance up to one mile. K-M analysis showed an estimated median RTW of 6 days for Excellent, 9 days for Good, 17 days for Fair, and 18 days for Poor Macnab outcomes. RTW analysis by the type of work showed estimated median RTW of 20 days for patients in the Heavy, 13 days in the Medium, and 6 days in the Light workgroup. The mean RT was 33.52 days in the Heavy, 19.17 days in the Medium, and 9.86 days in the Light workgroup (P<0.0001). The mean RTW was 22.27 days (P=0.008) in the Heavy, 13.97 days (P=0.004) in the Medium, and 7.58 days (P=0.004) in the Light workgroup. Postoperative irritation of the dorsal root ganglion (DRG) occurred in 68 of the 442 study patients (15.38%). DRG irritation delayed RTW to a mean of 18.94 days (P<0.0001) and RT to 15.31 days (P<0.001).

CONCLUSIONS

Patient RTW and RT data are "real-world" economic indicators of successful clinical outcomes with the lumbar endoscopic transforaminal decompression procedure and compare favorably to previously reported benchmarks for other types of translaminar surgeries. These median postoperative RTW and RT times with narcotic independence were on the order of 10 days or less in the vast majority of patients Excellent and Good outcomes (83.7%). The most relevant surgical predictor of delayed RTW and RT is a postoperative DRG irritation which predominantly affected patients adversely in the Medium and Heavy workgroups. These RTW and RT data may assist in the management of return-to-work expectations with the spinal endoscopy procedure.

Outcomes with transforaminal endoscopic versus percutaneous laser decompression for contained lumbar herniated disc: a survival analysis of treatment benefit

BACKGROUND

Contained lumbar disc herniations frequently cause back- and leg pain. Clinical outcomes with surgical treatment may be affected by the size and location of the disc herniation. The surgical directly visualized transforaminal endoscopic decompression has gained acceptance and popularity, while the simplified percutaneous laser disc decompression has fallen out of favor in spite of its initial success as a minimally invasive intervention. In an attempt to better understand the durability of both procedures, the authors performed a comparative analysis of clinical outcomes in patients with contained lumbar disc herniations.

METHODS

The study population was comprised 248 patients consisting of 162 patients in the endoscopy group (group 1) and 86 patients in the laser group (group 2). Primary outcome measures were Macnab criteria. Herniations were classified as large or small. Additional parameters of advanced degeneration of the lumbar motion segment including posterior disc- and lateral recess height of <3 mm were recorded. IBM SPSS 25.0 was used for Kaplan-Meier survival analysis and cross-tabulation of these variables with statistical testing for significant associations.

RESULTS

The mean follow-up was 43.5 months. The serial time recorded for Kaplan-Meier analysis ranged from 1.5 to 84 months. The mean age was 53.37 years (standard deviation =14.65 years). The majority of patients had Excellent and Good Macnab outcomes (212/248; 85.5%) regardless of treatment. Fair and Poor results were achieved in another 36 patients (14.5%). There was a higher percentage of Excellent Macnab outcomes in the endoscopy group (94/162; 58.0%) than in the laser group (38/86; 44.2%) at a statistical significant level (P<0.0001). There was a statistically significantly higher percentage of Excellent and Good Macnab outcomes with endoscopic decompression of small paracentral herniations (97.1%; P<0.0001). Percutaneous laser decompression of large central disc herniations was not statistically better than endoscopic surgical decompression (P=0.125). Endoscopic bony and soft tissue decompression was also better than laser at alleviating symptoms in patients with reduced posterior disc- and lateral recess height with 96.7% in patients with reduced disc height of <3 mm and 94% in patients with reduced lateral recess height of <3 mm (P=0.001). Kaplan-Meier (K-M) Survival time showed longer median survival of the treatment benefit for patients who underwent visualized endoscopic surgical decompression (66.0 months) compared to median K-M survival time for percutaneous laser decompression of 17 months (P<0.0001).

CONCLUSIONS

Transforaminal endoscopic decompression for symptomatic herniated disc is an effective and durable surgical treatment to alleviate sciatica-type and back symptoms in the vast majority of patients with good long-term survival of pain relief for up to six years. Interventional percutaneous non-visualized laser decompression for the same condition may provide favorable outcomes in the short-term with soft protrusions. However, the treatment effect deteriorates much faster with a median survival of 17 months.

Posterior percutaneous endoscopic lumbar discectomy combined with the vertical anchoring technique for lumbar disc herniation with distant upward migration

Background

Posterior percutaneous endoscopic lumbar discectomy (PELD) has become a preferred procedure for the treatment of simple lumbar disc herniation (LDH) but has rarely been reported for distant upward migration. The purpose of this research was to investigate the feasibility, safety, clinical efficacy and technical points of posterior PELD combined with the vertical anchoring technique (VAT) for the treatment of LDH with distant upward migration.

Methods

Thirteen patients with distant upward migrated LDH who underwent posterior PELD combined with the VAT from March 2016 to May 2018 were selected. Among these cases, the herniated disc was located at L3/4 in 2 patients, L4/5 in 9 patients and L5/S1 in 2 patients. The operative time, length of hospital stay and postoperative complications were recorded. The visual analogue score (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores and modified MacNab criteria were used to assess surgical efficacy.

Results

All 13 patients underwent successful surgery. We compared the VAS, ODI and JOA scores before and after surgery. The differences were statistically significant (P < 0.05). According to the modified MacNab criteria, 10 patients were assessed as “excellent”, 2 patients were assessed as “good” and 1 patient was assessed as “fair” at the last follow-up. The rate of satisfactory outcomes was 92.3%.

Conclusion

Posterior PELD combined with the VAT is a safe and feasible procedure for the treatment of LDH with distant upward migration and represents a new approach for this type of surgery.

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.

Transforaminal Endoscopic Discectomy and Foraminoplasty for Treating Central Lumbar Stenosis

Objective

Lumbar spinal stenosis is a medical condition characterized by the narrowing of the spinal canal as a consequence of bone and soft tissue degeneration, including disc herniation, facet and ligamentum flavum hypertrophy, and osteophyte formation. The percutaneous transforaminal endoscopic discectomy (PTED) technique is one of the emerging surgical alternatives for treating central lumbar stenosis. The present study aims to describe the present techniques of PTED and foraminoplasty for central lumbar stenosis, and discuss the feasibility and advantages of this technique.

Methods

A total of 55 patients with an average age of 50 years were recruited in this study. They were operated on between August 2017 and June 2018 by a single surgeon for symptomatic lumbar stenosis using the PTED and foraminoplasty technique, along with a detailed description of the present technique. The retrospective analysis of 55 patients operated between August 2017 and June 2018 by a single surgeon for symptomatic lumbar stenosis using the PTED and foraminoplasty techniques, and the detailed description of the present technique were the focus of the present study. For all patients, the PTED and foraminoplasty procedure was performed under local anesthesia in the lateral position on a radiolucent table using C‐arm fluoroscopy. The retrospective analysis evaluated the outcomes of symptoms through follow‐up interviews at six weeks, six months, and one year after surgery. The analyzed parameters included surgery time, intraoperative blood loss, postoperative complications, visual analog scale (VAS) score, Japan Orthopedic Association (JOA) score, and the Oswestry Disability Index (ODI). The modified MacNab criteria were adopted.

Results

The average duration of symptoms was 15.6 weeks. The mean operative time was 161 minutes. The mean volume of intraoperative blood loss was 21 mL. The mean follow‐up period was 14.6 months. The average preoperative VAS score for leg pain and low back pain was 6.8 and 5.5, respectively. The preoperative ODI and JOA score was 49.2 and 14.6, respectively. At the final follow‐up, all 55 patients had an average VAS score of 1.1 for leg pain and 0.5 for low back pain. At the same time, the average ODI and JOA score was seven and 24.5, respectively. The statistical analysis showed that the VAS score, ODI value, and JOA score were significantly lower in all time‐points at post‐operation, when compared to those at pre‐operation. For the modified MacNab criteria, the final outcome results were excellent in 39 patients (70.9%), good in nine patients (16.4%), fair in four patients (7.3%), and poor in two patients (3.6%), and the overall success rate was 89.1%. Two patients underwent a second operation during the follow‐up period, and their symptoms were released after the reoperation.

Conclusion

PTED and foraminoplasty technique showed promising outcomes in the treatment of central lumbar stenosis in a 1‐year follow‐up period. It suggested that PTED and foraminoplasty might be applied as a safe and effective therapeutic option for patients with lumbar stenosis.

Use of "Inside-Out" Technique for Direct Visualization of a Vacuum Vertically Unstable Intervertebral Disc During Routine Lumbar Endoscopic Transforaminal Decompression-A Correlative Study of Clinical Outcomes and the Prognostic Value of Lumbar Radiographs

Background

The purpose of this study was to record the frequency of lumbar intervertebral disc vacuum phenomenon on routine lumbar plain films taken prior to transforaminal endoscopic decompression surgery for sciatica-type leg and back pain and to correlate it with visualized intradiscal pathology and clinical outcomes.

Methods

A prospective case series study of 200 consecutive patients with an average mean follow-up of 41.85 months who underwent lumbar endoscopic transforaminal decompression at 236 lumbar levels was conducted. The sensitivity, specificity, and accuracy of vacuum phenomenon on preoperative x-ray to predict the presence of an empty vacuum disc found during transforaminal microdiscectomy using the "inside-out" approach were calculated using the YESS™ technique. Clinical outcomes were assessed by both Macnab criteria and visual analog score (VAS) reduction.

Results

Of the 200 patients evaluated, 124 (62%) were deemed to have a vacuum disc on intraoperative probing using the "inside-out" technique. During needle insertion the more severely degenerative discs are met with negative pressures manifested by an air discogram. According to Macnab criteria, all patients who also had extruded disc herniations had excellent results (8 of 200), with the mean VAS decreasing from 6.1 ± 2.6 preoperatively to 1.9 ± 1.4 at the final follow-up (P < .01). This indicates a more severely degenerative disc causing nonspecific back pain due to lack of anterior column support from the intervertebral disc, accentuating foraminal stenosis. Patients with contained disc herniations (62 of 200) had excellent and good results 82.2% of the time. The mean VAS decreased from 6.9 ± 1.7 preoperatively to 2.2 ± 1.1 at final follow-up (P < .01). This identifies the disc as a contributing factor in low back pain. It can also identify the disc and annulus in combination with foraminal stenosis as a contributing factor. In the spinal stenosis group (130 of 200), 81.5% of patients had excellent to good results, and the mean VAS decreased from 6.3 ± 1.5 preoperatively to 2.1 ± 1.2 at final follow-up (P < .01). An analysis of lumbar x-ray vacuum phenomenon in patients with visualized vacuum disc showed true-positive (35 patients) and false-negative (89 patients), compared with an x-ray negative grading in patients without intraoperatively visualized vacuum disc of false-positive (2 patients); and true-negative (74 patients); this allowed for calculation of sensitivity (28.2%), specificity (97.4%), and positive predictive value (94.6%) of preoperative diagnostic x-ray in relation to intraoperatively visualized presence of the vacuum disc during subsequent endoscopic decompression surgery. Direct endoscopic visualization of the inside of the vacuum disc revealed longitudinal fissuring of the intervertebral disc as the most common finding in 77 of the 124 patients (62.1%) with a vacuum disc. Cavitation with delamination was the second most common observation (21 patients). Fair outcomes were associated with cavitation and delamination of the intervertebral disc from the endplates (P < .0001).

Conclusions

A vacuum phenomenon seen on lumbar x-rays is highly specific for a source of one component that is actually a multiple source of nonspecific common back pain. A vacuum disc being found during "inside-out" transforaminal discectomy actually encompasses the disc, annulus, and foraminal stenosis as a multifactorial source of nonspecific common back pain. Further studies of better prognosticators of failed endoscopic transforaminal discectomy are required and are underway by the coauthors.

Comparison of Clinical Outcomes of Two-Level PELD and Foraminoplasty PELD for Highly Migrated Disc Herniations: A Comparative Study

Objective

The aim of this study is to compare the clinical outcomes of two-level percutaneous endoscopic lumbar discectomy (PELD) and foraminoplasty PELD in treating highly migrated lumbar disc herniations.

Methods

Patients with highly migrated lumbar disc herniations were enrolled from May 2014 to June 2016. Low back pain and leg pain were evaluated by the Visual Analog Scale (VAS), and functional outcomes were assessed with the Oswestry Disability Index (ODI). The satisfaction rate of clinical outcomes was assessed according to the modified MacNab criteria. In addition, the intraoperative duration and postoperative complications were also recorded.

Results

Forty patients, 14 cases in two-level PELD group and 26 cases in foraminoplasty PELD group, were included. The VAS scores of low back pain (P=0.67) and leg pain (P=0.86), as well as the ODI scores (P=0.87), were comparative between two-level PELD and foraminoplasty PELD groups. The satisfaction rate of clinical outcomes based on the modified MacNab criteria in the two-level PELD group was equivalent to that in foraminoplasty PELD group (92.9% versus 92.3%, P=0.92). In addition, the intraoperative duration of two-level PELD group was longer than that of foraminoplasty PELD group (80.2 ± 6.6 min versus 64.1 ± 7.3 min, P < 0.01). The postoperative complications in the two-level PELD group (postoperative dysesthesia: N = 1) were relatively fewer as compared to those in the foraminoplasty PELD group (postoperative dysesthesia: N = 1; recurrence: N = 1; nucleus pulposus residues: N = 1).

Conclusions

Both two-level PELD and foraminoplasty PELD are safe and effective surgical procedures for the patients with highly migrated lumbar disc herniations. Moreover, the two-level PELD technique has merits in reducing the incidence of postoperative nucleus pulposus residue.

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.

[Percutaneous Lumbar Endoscopic Discectomy: Presentation of 60 Cases Intervened in Argentina with Awake Patients]

INTRODUCTION

Percutaneous endoscopic lumbar discectomy (PELD) is a minimally invasive technique that has been used in different countries since the late eighties for the treatment of herniated discs.

OBJECTIVE

The objective of this study was to describe the results of PELD in a series of awake patients, treated with epidural anesthesia and mild sedation.

MATERIALS AND METHODS

In a group of 60 patients, who together had 77 discs operated on between April 2016 and March 2018, data were collected on patient age and gender, clinical presentation, and MRI abnormalities. The main outcome of interest was the difference between preoperative and postoperative Oswestry (Oswestry disability index [ODI]) scores 8 weeks after the procedure. Macnab criteria, operation duration, length of hospitalization, surgical complications, and the need for reoperation were other outcomes evaluated. All patients received epidural anesthesia and mild sedation.

RESULTS

The average reduction in ODI at 8 weeks was 48 points (standard deviation [SD] = 5), representing an average percentage reduction of 85% (SD = 8). By Macnab's criteria, 85% of patients experienced either an excellent or good result, while 10% and 5% had a fair and poor result, respectively. Average surgery time was 50 min and in-hospitalization stay 8.6 h.

CONCLUSIONS

In our series of surgical patients with lumbar disc herniations, PELD yielded very good results, manifest as significantly reduced pain, brief procedural durations, no complications, and short hospital stays. Patients accepted the option of being awake and immediately ambulatory, and the approach proved highly feasible to execute.

Transpedicular Endoscopic Surgery for Highly Downmigrated L5-S1 Disc Herniation

Endoscopic surgery for highly downmigrated disc herniation at level L5-S1 is a challenging technique. Most surgeons prefer the interlaminar access because of the special anatomy of the L5-S1 disc level, i.e., narrow neuroforamen and large interlaminar window. Transforaminal access to the neuroforamen L5-S1 is difficult in cases with high iliac crest. Here, the access to the highly downmigrated disc herniation with the recently reported technique of transpedicular endoscopic surgery by Krzok et al. was described. In 3 cases with highly downmigrated disc herniation of L5-S1, the sequester was removed successfully through the bone hole of S1 pedicle. This technique is demanding for experienced endoscopic surgeons.

The Concept for A Standalone Lordotic Endoscopic Wedge Lumbar Interbody Fusion: The LEW-LIF

OBJECTIVE

To review concepts of a standalone endoscopically assisted lumbar interbody fusion as a simplified method to treat spinal instability.

METHODS

MacNab outcomes and complications were analyzed in a series of 48 consecutive patients who underwent standalone lordotic endoscopic wedge lumbar interbody fusion (LEW-LIF) for advanced lumbar disc degeneration, spinal stenosis, and spondylolisthesis.

RESULTS

Forty-two of the 48 patients (77.8%) did well with excellent and good outcomes with a follow up of up to 20 months. Fair outcomes were reported by 4, and poor by another 2 patients, respectively. Six patients had endoscopic decompression procedures at another level. Four patients underwent open transforaminal lumbar interbody fusion revision surgery including the index level between 2 to 6 months postoperatively. An L5 vertebral body fracture was noted in 1 of these 4 patients. Another patient underwent removal of the extruded L3/4 cage. The cage fractured in one additional asymptomatic patient not requiring any intervention. No patient had a wound infection, or permanent sensory, or motor dysfunction. However, 29 patients developed a postoperative irritation of the dorsal root ganglion with burning leg pain typically between postoperative weeks 2 and 6. Symptoms were treated with activity modification, gabapentin, and transforaminal epidural steroid injections in 12 patients (25%).

CONCLUSION

Standalone LEW-LIF was associated with favorable clinical outcomes in the majority of patients. Patient-related predictors of less favorable outcomes considering normal variations as well as patho-anatomy may aid in the development of next-generation implants.

Does Preservation of Ligamentum Flavum in Percutaneous Endoscopic Lumbar Interlaminar Discectomy Improve Clinical Outcomes?

Objective

Ligamentum flavum (LF) is an important anatomical structure for prevention of postoperative adhesions, but the opening of LF is necessary for percutaneous endoscopic lumbar interlaminar discectomy (PEID). Although the defect in LF is small with conventional PEID, the defect could be minimized with LF splitting technique. The objective of this study was to compare clinical outcomes of PEID with opening of LF versus splitting of LF.

Methods

A retrospective study was performed for patients underwent PEID for L5–S1. PEID with the opening of LF (open-group) was performed for 55 patients and with splitting of LF (split-group) was performed for 34 patients. The defect of LF in Open-group was 3–5 mm, but the defect was negligible in split-group because the split LF was reapproximated by its elasticity. Clinical outcomes were evaluated with Korean version of the Oswestry Disability Index (K-ODI) and visual analogue pain scores for back (VASB) and leg (VASL). The changes of clinical outcomes during postoperative 24 months between groups were evaluated with linear mixed-effects model.

Results

The clinical outcomes were similar between groups for K-ODI (p=0.98), VASB (p=0.52), and VASL (p=0.59). Each outcome demonstrated significant improvement from preoperative baseline throughout the postoperative 24 months (p<0.05). Complications included recurrence in 4 patients and dural tear in 1 in open-group (9.1%), and residual disc herniation in 2 patients and transient weakness in 1 in split-group (8.8%).

Conclusion

Splitting versus opening LF in PEID may be left to the surgeon’s discretion. The potential risks and benefits of LF handling should be considered when performing this surgical technique in PEID.

Evolution of Spinal Endoscopic Surgery

Innovations in the development of endoscopic spinal surgery were classified into different generations and reviewed. Future developments and directions for endoscopic spinal surgery were discussed. Surgical therapy for spinal disease has been gradually changing from traditional open surgery to minimally invasive spinal surgery. Recently, endoscopic spinal surgery, which initially was limited to the treatment of soft tissue lesions, has expanded to include other aspects of spinal disease and good clinical results have been reported. As the paradigm of spinal surgery shifts from open surgery to endoscopic surgery, we discussed the evolution of endoscopic spine surgery in our literature review. Through this description, we presented possibilities of future developments and directions in endoscopic spine surgery.

Radiation Exposure and Operation Time in Percutaneous Endoscopic Lumbar Discectomy Using Fluoroscopy-Based Navigation System

OBJECTIVE

This study evaluated radiation exposure and operation time of percutaneous endoscopic lumbar discectomy (PELD) by using a fluoroscopy-based navigation system for access and localization.

METHODS

Eighty-six PELDs performed by a single surgeon were retrospectively analyzed. Patients were separated into 2 groups: group A (using a three-dimensional [3D]-printed navigation instrument and fluoroscopy-based navigation system) and group B (with conventional fluoroscopy and standard instrumentation). The operation, fluoroscopy, and total access time were collected, as well as fluoroscopy and access times.

RESULTS

The operative time for group A was 59 minutes (standard deviation [SD], 6 minutes) and 106 minutes (SD, 15 minutes) in group B (P < 0.001). In group A, fluoroscopy was used an average of 5 times (SD, 0.7) and 29 times (SD, 8) in group B (P < 0.001). The fluoroscopy time was 9 minutes (SD, 2 minutes) in group A and 40 minutes (SD, 8 minutes) in group B (P < 0.001). The number of access attempts was 1.3 (SD, 0.5) in group A and 8 (SD, 2 times) in group B (P < 0.001). The total access time was 11 minutes (SD, 2 minutes) in group A and 28 minutes (SD, 5 minutes) in group B (P < 0.001).

CONCLUSIONS

PELD using the fluoroscopy-based navigation system showed lower operative, fluoroscopy, and access time compared with conventional techniques. In addition, fewer fluoroscopy images and access attempts were made in the navigation group. These data suggest that this novel technique reduces fluoroscopy and operation time and may reduce risks of repeated surgical access attempts.

Incidence, Management, and Cost of Complications After Transforaminal Endoscopic Decompression Surgery for Lumbar Foraminal and Lateral Recess Stenosis: A Value Proposition for Outpatient Ambulatory Surgery

Objective

The objective of this study is to analyze incidence, estimate cost savings, and evaluate best management practices of complications resulting from outpatient transforaminal endoscopic decompression surgery for lumbar foraminal and lateral recess stenosis performed in an ambulatory surgery center.

Background

Endoscopic spinal surgery is gaining popularity for the treatment of lumbar disc herniations. Recent advances in surgical techniques allow for endoscopically assisted bony decompression for neurogenic claudication symptoms due to spinal stenosis. Postoperative complications from dural tears, recurrent disc herniations, nerve root injuries, foot drop, and facet and pedicle fractures, and postoperative sequelae such as dysesthetic leg pain and infiltration of the surgical access and spinal canal with irrigation fluid causing spinal headaches and painful wound swelling, as well as failure to cure, have been reported.

Methods

A retrospective study of 1839 consecutive patients with an average mean follow up of 33 months (range: 24 to 85 months) that underwent transforaminal endoscopic decompression surgery at 2076 levels between 2006 and 2015 was conducted to analyze incidence, and estimate the cost savings of postoperative adverse events following endoscopic foraminotomy and microdiscectomy. Complications were stratified using Dindo's 7-category grading system, distinguishing them from procedure-inherent sequelae as well as failure to cure. Only patients with unilateral radiculopathy due to either herniated disc or lateral recess stenosis were included in this study. Preoperatively, disc migration was graded by direction and distance from the disc space according to Lee's radiologic 4-zone classification. The type of disc herniation was classified either as contained or extruded. Contained herniations were further subclassified as disc protrusions versus disc bulges. In addition, the preoperative disc height was recorded. Bony spinal foraminal stenosis and lateral recess stenosis were graded on preoperative magnetic resonance imaging and computed tomography scans into mild, moderate, and severe by dividing the lumbar neuroforamen into 3 zones: (1) entry zone, (2) midzone, and (3) exit zone. Surgical outcomes were classified according to the Macnab criteria. In addition, reduction in the visual analog scale (VAS) scores were assessed.

Results

According to the Macnab criteria, excellent and good results were obtained in 82.2% of patients with extruded disc fragment (331/1839). In this group, the mean VAS score decreased from 5.9 ± 2.5 preoperatively to 2.4 ± 1.8 at final follow-up (P < .01). Patients with contained disc herniations (648/1839) had excellent and good results 72.7% of the time. In this group, the mean VAS score decreased from 7.2 ± 1.6 preoperatively to 3.1 ± 1.5 at final follow-up (P < .01). In the spinal stenosis group (860/1839), 75% of patients had excellent to good results. Postoperative grade I complications (any deviation from normal postoperative course treated with observation) occurred in 2 patients who immediately developed foot drop postoperatively on the surgical side (0.11%) and in another 2 patients (0.11%) with incidental durotomy. Grade II complications (any deviation with pharmacological interventions) occurred in 11 patients due to chronic obstructive pulmonary disease exacerbation, and in another 2 patients due to infections as the latter were successfully treated with antibiotics. Grade IIIb complications (any deviation requiring surgical, endoscopic, or radiological intervention under general anesthesia) occurred in 9 patients with reherniations of extruded discs within the first 3 postoperative months (recurrence rate 2.7%). Reherniations were associated with preserved disc height of > 6 mm (P < .02). Grade IV (organ failure), and grade V (death) complications did not occur. Procedure-inherent sequelae from adverse operative side effects were noted in 8 patients with spinal headaches (0.44%), and in 69 patients (3.75%), who had extravasations of irrigation fluid into the subcutaneous tissues causing wound swelling. Another 229 patients developed postoperative dysesthetic leg pain due to irritation of the dorsal root ganglion (12.45%), which was associated with severe foraminal stenosis (P < .01) and improved with supportive care in all cases. Failure to cure occurred in 39 patients (2.12%) with bony stenosis in the central canal, and lateral recess involving the entry zone of the neuroforamen and in 41 patients (2.23%) with contained disc herniations.

Conclusions

Complications after outpatient transforaminal endoscopic decompression surgery with respect to reherniation, wound infections, durotomy, and nerve root injury are approximately 1 magnitude lower than equivalent reported complication rates with microdiscectomy while delivering comparable clinical outcomes and lower readmission rates to an emergency room or hospital. Postoperative sequelae are typically self-limiting and successfully managed with supportive care measures. Significant cost savings are realized due to a considerably lower rate of decompensated postoperative medical problems.

Endoscopic transforaminal lumbar microdiscectomy. A retrospective analysis of 180 clinical cases

The authors performed retrospective analysis of 180 clinical cases of surgical treatment of lumbar herniated discs in patients who underwent endoscopic transforaminal microdiscectomy. This technique allows minimally invasive insertion of the endoscope into the spinal canal under local anaesthesia to decompress the nerve root by removing hernial protrusion under visual control. However, this technique is not universal and cannot be applied to all patients. Considerable practical experience has shown that the surgeon may encounter certain technical difficulties in cases of cranial or caudal sequester migration and in some cases when the access at L5–S1 level is complicated due to the high standing of the iliac crest. However, if there are correct indications, this technique allows to solve the problem of radicular compression syndrome in a short time.

Percutaneous endoscopic discectomy in adolescent lumbar disc herniation: a 3- to 5-year study

OBJECTIVEThe authors sought to investigate the efficiency of percutaneous endoscopic discectomy (PED) in adolescent patients with lumbar disc herniation (LDH), compare PED outcomes in adolescent patients with those in young adult LDH patients as controls, and discuss relevant technical notes.METHODSThis was a retrospective study involving 19 adolescent LDH patients (age > 13 and < 18 years, 20 discectomies) and 38 young adults (age < 40 years, 38 discectomies) who also had LDH and were matched to the adolescent group for sex and body mass index. The combined cohort included 51 male patients (89.5%) and 6 female patients (10.5%), with an average age of 26.7 years (range 14-39 years). The operated levels included L3-4 in 1 patient (1.7%), L4-5 in 22 patients (37.9%), and L5-S1 in 35 patients (60.4%). Two adolescents (10.5%) exhibited apophyseal ring separation and one (5.3%) had had previous PED. All patients underwent PED under local anesthesia. Outcomes were evaluated through a visual analog scale (VAS), the Japanese Orthopaedic Association (JOA) scoring system, and the modified MacNab grading system.RESULTSThe mean duration of follow-up was 41.7 months (range 36-65 months). The outcomes in adolescents were satisfactory and comparable with previously reported outcomes of microsurgical discectomy (MD) and conventional open discectomy (COD). The adolescent patients had a faster and better recovery course than the adult patients (p < 0.01). One adolescent patient (5.3%) exhibited recurrence and 2 adults (5.3%) experienced transient dysesthesia; the complication rates were comparable in the 2 age groups (p = 0.47). Prolonged duration of symptoms (p < 0.01) and disc degeneration (p = 0.01) were correlated with lower postoperative JOA values; patients with extrusions had higher postoperative JOA values than those with protrusions (p = 0.01).CONCLUSIONSPED may yield favorable results in the treatment of adolescent LDH in terms of short- to medium-term follow-up; restricted discectomy and a conservative rehabilitation program might be advisable. Further long-term studies are warranted to address this rare disease entity.

Outcomes of discectomy by using full-endoscopic visualization technique via the interlaminar and transforaminal approaches in the treatment of L5-S1 disc herniation: An observational study

The purpose of this retrospective study was to assess the clinical outcomes of discectomy by using full-endoscopic visualization technique via the interlaminar approach versus the transforaminal approach under general anesthesia in the treatment of L5-S1 disc herniation.Sixty patients with L5-S1 disc herniation were non-randomly recruited and assigned into two groups. One group (thirty patients) underwent discectomy by using full-endoscopic visualization technique via the interlaminar approach under general anesthesia, while the other group (thirty patients) underwent discectomy by using full-endoscopic visualization technique via the transforaminal approach under general anesthesia. The operative time, fluoroscopy time, and perioperative complications were recorded. The visual analog scale (VAS) score for leg and back pain and Oswestry disability index (ODI) score were evaluated preoperatively and at 3, 6, and 18 months postoperatively.The mean operative time and fluoroscopy time in the interlaminar group were significantly shorter compared with those in the transforaminal group. The mean VAS and ODI postoperative scores were significantly improved over the preoperative scores in both groups. According to the MacNab classification system, more than 90.0% of the patients achieved an excellence/good rating in both groups. An intraoperative epineurium injury occurred in both groups. The total recurrence rate during 18 months follow-up was 3.3% in the interlaminar group and 0% in the transforaminal group.It is efficient and safe to perform discectomy by using full-endoscopic visualization technique via both interlaminar and transforaminal approaches under general anesthesia in patients with L5-S1 disc herniation. Discectomy performed by using full-endoscopic visualization technique via the interlaminar approach requires a shorter operative time and suffers less radiation exposure than the transforaminal approach.

Percutaneous Endoscopic Lumbar Discectomy for Highly Upmigrated Disc Herniation Through the Transforaminal Isthmus Plasty Approach

BACKGROUND

Highly upmigrated herniation can be difficult to remove using percutaneous endoscopic lumbar discectomy (PELD) and the conventional transforaminal approach. Although many surgeons have constantly explored new techniques and approaches, we still lack a more effective, convenient, and economical technique to treat highly upmigrated herniation. We have described a novel approach, the transforaminal isthmus plasty approach, for PELD to treat highly upmigrated disc herniation.

CASE DESCRIPTION

A 72-year-old man with L3-L4 highly upmigrated disc herniation, who had experienced no relief after a long period of conservative treatment, underwent PELD through the transforaminal isthmus plasty approach. The operation was successful, and he experienced significant symptom relief after the surgery.

CONCLUSIONS

The transforaminal isthmus plasty approach is an effective and viable alternative approach for PELD to treat highly upmigrated disc herniation.

Readmissions After Outpatient Transforaminal Decompression for Lumbar Foraminal and Lateral Recess Stenosis

Background

The objective of this study was to analyze readmission rates after outpatient transforaminal endoscopic decompression surgery for lumbar foraminal and lateral recess stenosis done in an ambulatory surgery center. Endoscopic lumbar spinal surgery is gaining popularity for the treatment of lumbar disc herniations. Recent advances in surgical techniques allow for percutaneous endoscopically assisted bony decompression for neurogenic claudication symptoms due to spinal stenosis. The surgery can be done under local anesthesia and sedation. Patients may be discharged home within hours from surgery, and complications are rare. However, readmissions for recurrent disc herniations, failure of pain relief, dysesthetic leg pain, nerve root injuries with foot drop, and facet and pedicle fractures have been reported.

Methods

A retrospective study of 1839 consecutive patients with an average mean follow up of 33 months (range 24 to 85 months) that underwent percutaneous endoscopic surgery at 2076 levels between 2006 and 2015 was conducted with the intent of identifying factors associated with emergency room or hospital readmission following endoscopic foraminotomy and microdiscectomy. Only patients with unilateral radiculopathy due to either herniated disc or lateral recess stenosis were included in this study. Preoperatively, disc migration was graded by direction and distance from the disc space according to Lee's radiologic 4-zone classification. The type of disc herniation was classified either as extruded or contained. Contained herniations were further subclassified as disc protrusions versus disc bulges. In addition, the preoperative disc height was recorded. Bony spinal foraminal stenosis and lateral recess stenosis were graded on preoperative magnetic resonance imaging and computed tomography scans into mild, moderate, and severe by dividing the lumbar neuroforamen into 3 zones: (a) entry zone, (b) midzone, and (c) exit zone. Surgical outcomes were classified according to the Macnab criteria. In addition, reduction in visual analog scores (VASs) were assessed. The treating physician (KUL) performed all surgeries.

Results

According to the Macnab criteria, excellent and good results were obtained in 82.2% of patients with extruded disc fragment (331/1839). In this group, the mean VAS decreased from 5.9 ± 2.5 preoperatively to 2.4 ± 1.8 at the final follow up (P < .01). Patients with contained disc herniations (648/1839) had excellent and good results 72.7% of the time. In this group, the mean VAS decreased from 7.2 ± 1.6 preoperatively to 3.1 ± 1.5 at the final follow up (P < .01). In the spinal stenosis group (860/1839), 75% of patients had excellent to good results. There were no major approach-related complications. Sixty-nine patients had extravasations of irrigation fluid into the subcutaneous tissues (3.8%). Eight patients developed spinal headaches (0.4%). Two patients developed foot drop on the surgical side immediately postoperatively (0.1%). Reherniations of extruded discs occurred in 9 patients (2.7% recurrence rate). Failure of pain relief without significant improvement of walking endurance occurred in 29 patients with bony stenosis in the central canal, lateral recess, and entry zone of the neuroforamen (3.3%). Reherniations were associated with preserved disc height of >6 mm (P < .02). Dysesthetic leg pain due to dorsal root ganglion irritation occurred in 229 patients (12.4%) and was unrelated to case frequency but was associated with severe foraminal stenosis (P < .01). All 229 patients improved with supportive care. Facet or pedicle fractures did not occur in this series. There were 26 acute care (within 6 weeks from surgery) postoperative emergency room visits [16 of which resulted in readmission to a hospital over the 9-year study period (0.86%): 9 for dysesthetic leg pain, 2 for wound infections, and 5 for poorly controlled incisional pain].

Conclusions

Transforaminal endoscopic decompression can be successfully carried out in an outpatient surgery center setting. Readmissions due to reherniations, postoperative complications, or poor pain control are uncommon.