Endoscopic Lumbar Surgery: The State of the Art in 2019

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Spinal Injections: A Narrative Review from a Surgeon's Perspective

Spinal pain is one of most frequent complaints of the general population, which can cause decreased activities of daily living and absence from work. Among numerous therapeutic methods, spinal injection is one of the most effective treatments for spinal pain and is currently widely applied in the clinical field. In this review, spinal injection is discussed from a surgeon's perspective. Recently, although the number of spinal surgeries has been increasing, questions are arising as to whether they are necessary. The failure rate after spinal surgery is high, and its long-term outcome was reported to be similar to spinal injection. Thus, spinal surgeries should be performed conservatively. Spinal injection is largely divided into diagnostic and therapeutic blocks. Using diagnostic blocks, such as the diagnostic selective nerve root block, disc stimulation test, and diagnostic medial branch block (MBB), the precise location causing the pain can be confirmed. For therapeutic blocks, transforaminal nerve root injection, therapeutic MBB, and percutaneous epidural neuroplasty are used. When unbearable spinal pain persists despite therapeutic spinal injections, spinal surgeries can be considered. Spinal injection is usefully used to identify the precise location prior to a patient undergoing injection treatment or surgery and can reduce pain and improve quality of life, and help to avoid spinal surgery. Pain physicians should treat patients with spinal pain by properly utilizing spinal injection.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Bibliographic Study and Meta-Analysis of Clinical Outcomes of Full-Endoscopic Spine Surgery for Painful Lumbar Spine Conditions

BACKGROUND

Full-endoscopic spine surgery (FESS) indications already cover degenerative, infectious, and neoplastic diseases. This study aimed to use a bibliometric search and meta-analysis of the highest-quality studies in the last 20 years to determine the quantity and quality of FESS research, geographic distribution, and the outcomes for lumbar conditions.

METHODS

Articles on FESS published from 2000 to 2022 were screened and assessed through Web of Science, PubMed, and Scopus. Also, databases were searched for longitudinal studies to pool in a meta-analysis of patients undergoing FESS for lumbar conditions. After stratifying the risk of bias and having collected the studies of the highest quality, we included the proportion of patients with a satisfactory outcome and intraoperative and postoperative adverse events after the analysis of lumbar spine conditions.

RESULTS

A total of 728 articles were identified by the bibliographic search. Between 2000 and 2021, the published articles increased 21-fold. Most were from China (70.15%), followed by South Korea (19.5%). Most were retrospective (68.3%) and regarding treatment of lumbar disease (86.4%). Fifty studies, including 34,828 patients, were pooled in the meta-analysis. More than 85% of patients experienced satisfactory improvement in each of different lumbar conditions. Major adverse events were <2%; recurrence and postoperative dysesthesia rates were within those reported for open or mini-invasive procedures.

CONCLUSIONS

This study may fill research gaps on FESS and lead to adequately designed studies. Our meta-analysis showed that FESS for lumbar diseases is a procedure with satisfactory outcomes and low rates of adverse events.

Percutaneous Transforaminal Endoscopic Discectomy Versus Microendoscopic Discectomy for Lumbar Disk Herniation: Five-year Results of a Randomized Controlled Trial

STUDY DESIGN

A prospective randomized controlled study.

OBJECTIVE

To compare the efficacy and safety between percutaneous transforaminal endoscopic discectomy (PTED) and microendoscopic discectomy (MED).

SUMMARY OF BACKGROUND DATA

Two kinds of minimally invasive discectomy, PTED and MED, are now widely used for treating lumbar disk herniation (LDH). The long-term comparative results of these two techniques still remained uncertain.

MATERIALS AND METHODS

In this single-center, open-label, randomized controlled trial, patients were included if they had persistent signs and symptoms of radiculopathy with corresponding imaging-confirmed LDH and were randomly allocated to PTED or MED groups. The primary outcome was the score of Oswestry Disability Index (ODI) and the secondary outcomes included the score of Medical Outcomes Study 36-Item Short-Form Health Survey bodily pain (SF36-BP) and physical function (SF36-PF), European Quality of Life-Five Dimensions (EQ-5D), Visual Analog Scales for back pain (VAS-back) and leg pain (VAS-leg).

RESULTS

A total of 241 patients were accepted to enroll in our randomized controlled trial, of which 119 were randomly assigned to the PTED group, and the rest 122 were assigned to the MED group. A total of 194 out of 241 patients (80.5%) completed the five-year follow-up. PTED group was associated with shorter postoperative in-bed time and length of hospital stay. Both primary and secondary outcomes did not differ significantly between the two treatment groups at each follow-up time point. During the five-year follow-up, seven recurrent cases occurred in PTED and MED groups, respectively.

CONCLUSION

Over the five-year follow-up period, PTED and MED were both efficacious in the treatment of LDH. The long-term clinical outcomes and recurrent rates were comparable between the treatment groups. PTED represents a more minimally invasive technique with the advantages of rapid recovery.

Modified lumbar foraminoplasty using a power-aided reciprocating burr for percutaneous transforaminal endoscopic lumbar discectomy: A technical note and clinical report

Background

One of the main difficulties in a transforaminal endoscopic lumbar discectomy (TELD), and simultaneously the most critical step, is performing an effective and safe foraminoplasty, which is especially difficult for beginners. To make it safer and faster for beginners to perform, we have used a specially designed power-aided reciprocating burr for TELD and reported the technical details.

Methods

From Jan. 2019 to Nov. 2022, 432 patients with single-level, symptomatic L4/5 or L5/S1 disc herniation were treated with TELD using a novel power-aided reciprocating burr. The surgical procedure is described in detail. Magnetic resonance imaging (MRI) was performed the following day and 3 months after the operation. The learning curves of surgeons with different seniority levels are displayed. The Visual Analogue Scale (VAS) score and the Oswestry Disability Index (ODI) were used to measure low back pain, leg pain, and lumbar function. All patients were followed up for at least 1 year.

Results

All patients underwent endoscopic surgery successfully. Among the 432 patients, radicular outer membrane damage was observed in 6 cases, and 1 case had hernia of the nerve tract. Except for this patient with aggravation of postoperative numbness, the postoperative neurological symptoms of all patients were significantly improved. The mean VAS scores for low back pain and leg pain and ODI scores were significantly decreased 6 w post-operatively and were maintained until 12 months post-operatively compared to preoperative scores (P < 0.05). All three doctors involved in the study had substantial experience in traditional open spinal surgery. The more operations all three surgeons completed, the more time spent on intervertebral foraminoplasty decreased (P < 0.05). Among them, doctors without experience in TELD surgery became proficient in this technique after accumulating experience in 13 cases. There was no significant difference in foraminoplasty time among these three surgeons during the same growing period (P > 0.05).

Conclusions

Current clinical data demonstrated the safety and efficacy of modified TELD using a power-aided reciprocating burr for treating lumbar disc herniation (LDH) and showed that this technique significantly reduces the learning curve for beginners when performing foraminoplasty.

Ultrasound-Guided In-Plane Interlaminar Lumbar Endoscopic Approach with Smartphone and Portable Light Source: Description of a New Surgical Technique

Introduction Endoscopic spine surgery enables the minimally invasive treatment of pathologies affecting the spinal cord and roots. Herein we describe an unprecedented technique Ultrasound-Guided in-plane interlaminar lumbar endoscopic approach with a smartphone and portable light source.

Methods The interlaminar approach was performed in a cadaveric specimen at L4 to 5 and L5 to S1 bilaterally. A curvilinear 2 to 5 MHz ultrasound probe was employed, the puncture was performed with the needle, a guide wire was inserted until the flavum ligament, followed by the dilator and working cannula. A 30° spinal endoscope, with an optical adapter of the endoscope camera for smartphone and portable endoscope lighting was inserted, the flavum ligament was visualized, and an opening in this site was performed with the scissors. Open dissection of the specimen was subsequently performed by identifying the puncture site in the interlaminar window.

Results The four interlaminar punctures were successfully guided by ultrasound; the opening of the ligamentum flavum was performed in the most lateral part of the interlaminar space, near the junction of the superior and inferior articular processes of the corresponding vertebrae in all the punctures.

Discussion The ultrasound makes possible to identify facets, foramina, transverse processes, and the interlaminar space. It is possible to minimize the use of radioscopy and its associated risks, both for patients and health professionals.

Conclusions The ultrasound-guided, in-plane, interlaminar, lumbar endoscopic approach with smartphone-adapted endoscope and portable light source is feasible and practical, minimizing radiation risks and making it possible to perform endoscopic spinal surgery.

Percutaneous full-endoscopic uniportal decompression for the treatment of symptomatic idiopathic lumbar spinal epidural lipomatosis: Technical note

Background

Lumbar spinal epidural lipomatosis (SEL) is a rare condition characterized by an excessive accumulation of adipose tissue within the spinal canal, compressing the dura sac and/or nerve roots. When conservative treatments fail and clinical symptoms progress quickly and seriously, surgical decompression should be considered. With the rapid development of endoscopic armamentaria and techniques, the pathological scope that can be treated by percutaneous endoscopic spine surgery is ever expanding.

Objective

In this paper, the authors describe a patient with lumbar spinal epidural lipomatosis who was treated with a percutaneous full-endoscopic uniportal decompression surgery successfully. This article aims to validate the feasibility of percutaneous full-endoscopic uniportal decompression for the treatment of symptomatic idiopathic spinal epidural lipomatosis via interlaminar approach.

Methods

We describe a case of a 69-year-old man with a 10-year history of low back pain, intermittent claudication, and bilateral leg neuropathic pain. He was diagnosed with lumbar epidural lipomatosis, which did not respond to conservative therapy. After a comprehensive evaluation, he underwent percutaneous endoscopic spine surgery to remove hyperplastic adipose tissue and decompress nerve roots and dura sac.

Results

The patient was treated with a percutaneous full-endoscopic uniportal decompression surgery successfully. After the procedure, his leg pain decreased and his walking capacity improved. There were no surgery-related complications, such as cerebrospinal fluid leakage, incision infection, etc.

Conclusions

The case with SEL was successfully treated with a percutaneous full-endoscopic uniportal surgery, which has the advantages of excellent presentation of anatomical structures, expanded field of vision, less surgical-related trauma, and bleeding. The key point of the procedure is to release and cut off the bands which divide the epidural space into small rooms filled with excess adipose tissue.

Spine Surgery Assisted by Augmented Reality: Where Have We Been?

This present systematic review examines spine surgery literature supporting augmented reality (AR) technology and summarizes its current status in spinal surgery technology. Database search strategies were retrieved from PubMed, Web of Science, Cochrane Library, Embase, from the earliest records to April 1, 2021. Our review briefly examines the history of AR, and enumerates different device application workflows in a variety of spinal surgeries. We also sort out the pros and cons of current mainstream AR devices and the latest updates. A total of 45 articles are included in our review. The most prevalent surgical applications included are the augmented reality surgical navigation system and head-mounted display. The most popular application of AR is pedicle screw instrumentation in spine surgery, and the primary responsible surgical levels are thoracic and lumbar. AR guidance systems show high potential value in practical clinical applications for the spine. The overall number of cases in AR-related studies is still rare compared to traditional surgical-assisted techniques. These lack long-term clinical efficacy and robust surgical-related statistical data. Changing healthcare laws as well as the increasing prevalence of spinal surgery are generating critical data that determines the value of AR technology.

Risk Factors for Poor Outcomes Following Minimally Invasive Discectomy: A Post Hoc Subgroup Analysis of 2-Year Follow-up Prospective Data

Objective

A post hoc subgroup analysis of prospectively collected data from a randomized controlled trial was conducted to identify risk factors related to poor outcomes in patients who underwent minimally invasive discectomy.

Methods

Patients were divided into satisfied and dissatisfied subgroups based on Oswestry Disability Index (ODI), visual analogue scale (VAS) back pain score (VAS-back) and leg pain score (VAS-leg) at short-term and midterm follow-up according to the patient acceptable symptom state threshold. Demographic characteristics, radiographic parameters, and clinical outcomes between the satisfied and dissatisfied subgroups were compared using univariate and multivariate analysis.

Results

A total of 222 patients (92.1%) completed 2-year follow-up, and the postoperative ODI, VAS-back, and VAS-leg were significantly improved after surgery as compared to preoperatively. Multivariate analysis indicated older age (p=0.026), lateral recess stenosis (p=0.046), and lower baseline ODI (p=0.027) were related to poor short-term functional improvement. Higher baseline VAS-back (p=0.048) was associated with poor short-term relief of back pain, while absence of decreased sensation (p=0.019) and far-lateral disc herniation (p=0.004) were associated with poorer short-term relief of leg pain. Lumbar facet joint osteoarthritis was identified as a risk factor for poor functional improvement (p=0.003) and relief of back pain (p=0.031). Disc protrusion (p=0.036) predicted poorer relief of back pain at midterm follow-up.

Conclusion

In this study, several factors were identified to be predictive of poor surgical outcomes following minimally invasive discectomy. (ClinicalTrials.gov number: NCT01997086).

A Review of Endoscopic Spine Surgery: Decompression for Radiculopathy

PURPOSE OF REVIEW

With this manuscript the authors sought to write a succinct review of the origins, as well as the latest advancements in endoscopic spine surgery to serve as a reference frame for physicians looking to learn this approach.

RECENT FINDINGS

At its infancy, the indications for posterolateral and transforaminal endoscopic decompression remained narrow, which prevented the procedure from gaining rapid traction during those days. However, more recently the tides have turned and an increasing number of surgeons are starting to adopt this technique given all its advantages. With the advent of higher quality camera systems and instruments, indications to use a minimally invasive option have gotten significantly broader. The most basic indication for the use of this technology is a soft disc herniation causing compromise of a neural structure that has failed to be managed successfully with non-surgical therapies. The use of endoscopic techniques provides significant advantages to patient outcomes and patient recovery. Endoscopic procedures should not be used as a blanket approach to nerve root decompression, as they certainly have limitations. Most contraindications to this procedure are relative and serve mostly as points to consider when selecting the methods to address neural compression. As these techniques become more widely accepted, we expect its reach and indications to continue to broaden and diversify. The full integration of navigation technologies will likely leapfrog this procedure into the mainstream use.

Robotic-Assisted Trajectory Into Kambin's Triangle During Percutaneous Transforaminal Lumbar Interbody Fusion-Initial Case Series Investigating Safety and Efficacy

BACKGROUND

Minimally invasive spine surgery (MISS) has the potential to further advance with the use of robot-assisted (RA) techniques. While RA pedicle screw placement has been extensively investigated, there is a lack of literature on the use of the robot for other tasks, such as accessing Kambin's triangle in percutaneous lumbar interbody fusion (percLIF).

OBJECTIVE

To characterize the surgical feasibility and preliminary outcomes of an initial case series of 10 patients receiving percLIF with RA cage placement via Kambin's triangle.

METHODS

We performed a single-center, retrospective review of patients undergoing RA percLIF using robot-guided trajectory to access Kambin's triangle for cage placement. Patients undergoing RA percLIF were eligible for enrollment. Baseline health and demographic information in addition to peri- and postoperative data was collected. The dimensions of each patient's Kambin's triangle were measured.

RESULTS

Ten patients and 11 levels with spondylolisthesis were retrospectively reviewed. All patients successfully underwent the planned procedure without perioperative complications. Four patients underwent their procedure with awake anesthesia. The average dimension of Kambin's triangle was 66.3 m2. With the exception of 1 patient who stayed in the hospital for 7 d, the average length of stay was 1.2 d, with 2 patients discharged the day of surgery. No patients suffered postoperative motor or sensory deficits. Spinopelvic parameters and anterior and posterior disc heights were improved with surgery.

CONCLUSION

As MISS continues to evolve, further exploration of robot-guided surgical practice, such as our technique, will lead to creative solutions to challenging anatomical variation and overall improved patient care.

Spinal metastasis: The rise of minimally invasive surgery

INTRODUCTION

Bone is the third most common site of metastatic cancer, of which the spine is the most frequently involved. As metastatic cancer prevalence rises and surgical techniques advance, operative intervention for spinal metastases is expected to rise. In the first operative cohort of spinal metastasis in Ireland, we describe the move towards less invasive surgery, the causative primary types and post-operative survival.

METHODS

This is a retrospective cohort study of all operative interventions for spinal metastasis in a tertiary referral centre over eight years. Primary spinal tumours and local invasion to the spine were excluded. Median follow up was 1895 days.

RESULTS

225 operative procedures in 196 patients with spinal metastasis were performed over eight years. Average cases per year increased form 20 per year to 29 per year. Percutaneous procedures became more common, accounting for the majority (53%) in the final two years. The most common primary types were breast, myeloma, lung, prostate and renal. Overall survival at 1 year was 51%. Primary type was a major determinant of survival, with breast and the haematological cancers demonstrating good survival, while lung had the worst prognosis.

CONCLUSION

This is the first descriptive cohort of operative interventions for spinal metastasis in an Irish context. Surgery for spinal metastasis is performed at an increasing rate, especially through minimally-invasive means. The majority of patients survive for at least one year post-operatively. Prudent resource planning is necessary to prepare for this growing need.

Comparison of two endoscopic spine surgical techniques

OBJECTIVE

The objective of this study is to compare the clinical outcome among patients who are surgically treated for lumbar disc herniation by transforaminal and interlaminar endoscopy techniques.

METHODS

For the treatment of lumbar disc herniation, 31 patients were assigned to undergo the interlaminar technique and 24 patients the transforaminal technique. They were evaluated using visual analog scale and Oswestry disability index in the preoperative period, in the first postoperative period, and in the 12th month after the procedure. The clinical results between the two techniques were then compared.

RESULTS

Overall, 89.1% of the patients obtained good results, with 12.5% complications in the transforaminal technique and 9.6% in the interlaminar technique.

CONCLUSION

Although both the endoscopic techniques, compared in this study, are safe and effective for the surgical treatment of lumbar herniated disc, the interlaminar technique presented significantly better results and lower rates of complications than the transforaminal technique.

Dural Injury in Unilateral Biportal Endoscopic Spinal Surgery

STUDY DESIGN

Retrospective study.

OBJECTIVES

Unilateral biportal endoscopic surgery (UBES) is a popular surgical method used to treat degenerative spinal diseases because of its merits, such as reduced tissue damage and outstanding visual capacity. However, dural injury is the most common complication of UBES with an incidence rate of 1.9% to 5.8%. The purpose of this study was to analyze the pattern of dural injury during UBES and to report the clinical course.

METHODS

We retrospectively reviewed the medical and radiographic records of surgically treated patients who underwent UBES at a single institute between January 2018 and December 2019.

RESULTS

Fifty-three patients, representing 67 segments, underwent UBES. Seven dural injuries occurred, and the incidence rate was 13.2%. Among 16 far lateral approaches, 2 dural injuries of the exiting roots occurred and were treated with fibrin sealant reinforcement. Among 51 median approaches, dural injury occurred at the thecal sac (n = 3) and traversing root (n = 2). A dural injury of the shoulder of the traversing root was treated with a fibrin sealant; however, a defect in the thecal sac required a revision for reconstruction. The other 2 thecal sac injuries were directly repaired via microscopic surgery.

CONCLUSIONS

Dural injury during UBES can occur because of the various anatomical features of the meningo-vertebral ligaments. Direct repair of the central dural defect should be considered under microscopic vision. A linear tear in the lateral dura or root can be controlled with a simple patchy reinforcement under endoscopic vision.

Percutaneous Full-Endoscopic C2 Ganglionectomy for the Treatment of Intractable Occipital Neuralgia: Technical Note

BACKGROUND

The C-2 dorsal root ganglionectomy procedure can provide effective treatment for intractable occipital neuralgia (ON). However, the traditional microsurgery of C2 ganglionectomy needs a wide incision and significant paraspinous muscle dissection for adequate visualization. The indications of endoscopic spine surgery are ever expanding, with the development of endoscopic armamentaria and technological innovations.

OBJECTIVE

To validate the feasibility of the approach and describe several operative nuances based on the authors' experience. In this paper, the authors describe a patient with intractable ON who was successfully treated with a percutaneous full-endoscopic C2 ganglionectomy.

METHODS

We describe the case of an 83-yr-old female with a 2-yr history of left ON who did not respond to a series of treatments, including physical therapy, drug therapy, injection therapy, and radiofrequency therapy. After careful examination, we performed a percutaneous, full-endoscopic left C2 ganglionectomy.

RESULTS

The patient was successfully treated with a percutaneous full-endoscopic ganglionectomy. Afterwards, her intractable and constant pain was relieved. There was no cerebrospinal fluid leakage, incision infection, neck deformity, or other complications.

CONCLUSION

C2 ganglionectomy can be accomplished successfully using a full-endoscopic uniportal surgical technique under continuous irrigation, which has the advantages of excellent illumination and visualization, reduced surgery-related trauma, and reduced bleeding.

Surgical outcomes of decompression alone versus transpedicular screw fixation for upper lumbar disc herniation

Background

Surgical outcomes of upper lumbar disc herniations (ULDHs) including T12-L1, L1-L2, and L2-L3 levels are characteristically less favorable and more unpredictable.

Objectives

This study was conducted to compare the surgical outcomes of decompression alone versus decompression combined with transpedicular screw fixation in treating upper lumbar disc herniation.

Methods

This retrospective cohort study was carried out at Neurosurgery Departments, Tanta University. The study included 46 patients with a symptomatic high lumbar herniated disc at T12-L1, L1-L2, and L2-L3 levels. The enrolled patients were divided into two groups depending on whether they were operated on via decompression and partial medial facetectomy (group 1, 22 patients) or via the previous maneuver plus transpedicular screw fixation (group 2, 24 patients). All patients were medically evaluated immediately after the operation; then, they were followed up at the 3rd and the 6th months following surgery. Patients’ outcomes were assessed by visual analogue score (VAS) and Oswestry Disability Index (ODI) scores.

Results

Median VAS scores in each group revealed significant reduction immediately following surgery and at each of 7 days, 3 months, and 6 months in comparison with the preoperative VAS score (p<0.001). Furthermore, each group showed significant stepwise reduction in the median ODI score at the 3rd and the 6th months postoperative compared to the preoperative ODI score (group 1 = 68.0, 19.0, 15.0; p< 0.001 and group 2 = 66.5, 20.0, 15.0; p< 0.001), with no significant differences between both groups (p> 0.05).

Conclusions

Both standalone decompression and decompression combined with transpedicular screw fixation revealed comparable favorable outcomes in patients with ULDH.

Automatic tip detection of surgical instruments in biportal endoscopic spine surgery

BACKGROUND

Recent advances in robotics and deep learning can be used in endoscopic surgeries and can provide numerous advantages by freeing one of the surgeon's hands. This study aims to automatically detect the tip of the instrument, localize a point, and evaluate the detection accuracy in biportal endoscopic spine surgery (BESS). The tip detection could serve as a preliminary study for the development of vision intelligence in robotic endoscopy.

METHODS

The dataset contains 2310 frames from 9 BESS videos with x and y coordinates of the tip annotated by an expert. We trained two state-of-the-art detectors, RetinaNet and YOLOv2, with bounding boxes centered around the tip annotations with specific margin sizes to determine the optimal margin size for detecting the tip of the instrument and localizing the point. We calculated the recall, precision, and F1-score with a fixed box size for both ground truth tip coordinates and predicted midpoints to compare the performance of the models trained with different margin size bounding boxes.

RESULTS

For RetinaNet, a margin size of 150 pixels was optimal with a recall of 1.000, precision of 0.733, and F1-score of 0.846. For YOLOv2, a margin size of 150 pixels was optimal with a recall of 0.864, precision of 0.808, F1-score of 0.835. Also, the optimal margin size of 150 pixels of RetinaNet was used to cross-validate its overall robustness. The resulting mean recall, precision, and F1-score were 1.000 ± 0.000, 0.767 ± 0.033, and 0.868 ± 0.022, respectively.

CONCLUSIONS

In this study, we evaluated an automatic tip detection method for surgical instruments in endoscopic surgery, compared two state-of-the-art detection algorithms, RetinaNet and YOLOv2, and validated the robustness with cross-validation. This method can be applied in different types of endoscopy tip detection.

Complete resolution of chronic pain, sensory impairment, and motor dysfunction following percutaneous transforaminal endoscopic decompression in a failed back surgery syndrome patient-a case report

Failed back surgery syndrome (FBSS) is an increasingly common problem that presents a clinical challenge. Though usual treatments may improve pain for some period of time, they do not provide clinically significant recovery of subjective numbness and weakness. We describe a case of a 48-year-old female with FBSS, who presented to the pain clinic with a 29-year history of low back pain, and a 7-year history of sensory and motor dysfunction of her left lower extremity, ever since a left hemi-laminectomy. At the time of presentation, she was wheelchair bound with intense pain, 4/5 strength in her left lower extremity proximally, and 3/5 strength distally. She had previously failed conservative management including medications, physical therapy, and epidural and facet injections. During percutaneous transforaminal endoscopic decompression, her transiting left L5 nerve root was found to be encased in thick scar tissue. The entirety of this scar tissue entrapping her L5 nerve was able to be released, resulting in not only complete resolution of pain but full return of sensory and motor function; in fact, the patient was able to walk out of the post anesthesia care unit without any assistive devices. Despite long-standing damage from many years of nerve entrapment, this patient's sensory and motor function was able to be restored simply by freeing her nerve of scar tissue. Thus, if nerve entrapment in scar tissue is the cause of FBSS, transforaminal endoscopic decompression may offer not only pain relief, but also return of sensory and motor function.

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.

A Narrative Review of Development of Full-Endoscopic Lumbar Spine Surgery

In the first phase of development of lumbar endoscopic spine surgery, the focus was on removal of soft disc material through the working corridor of Kambin’s triangle using transforaminal endoscopic lumbar discectomy. With the introduction of the interlaminar approach and increased interest from both industry and surgeons, there has been an exponential development of endoscopic surgical equipment and a corresponding expansion of endoscopic techniques. Endoscopic treatment strategies are applied to conditions ranging from contained prolapsed intervertebral discs to noncontained migrated herniated discs, hard calcified discs, spinal stenosis in the central or lateral recess and the foraminal and extraforaminal region, and other combinations of degenerative conditions requiring decompression or fusion surgery. The further expansion of endoscopic surgical management involving complicated spinal cases and the final quartet of trauma, infections, tumors, and possibly deformities could be the future stage of endoscopic spine surgery development. This article covers the full range of current treatment strategies and presents possible future developments of endoscopic spine surgery for the management of lumbar spinal conditions.

Awake Endoscopic Transforaminal Lumbar Interbody Fusion: A Technical Note

BACKGROUND

Advances in modern spinal fusion techniques have allowed for less peri-operative morbidity and more rapid recovery from surgery. The addition of endoscopy to minimally invasive surgery (MIS) fusion techniques represents the latest progression of efforts to minimize the impact of surgical intervention.

TECHNIQUE

MIS transforaminal lumbar interbody fusion (TLIF) is performed endoscopically through a sub-centimeter working portal. Patients undergo light conscious sedation and remain awake to facilitate feedback with the surgeon and enhance post-operative recovery.

RESULTS

Previously reported results of the first 100 cases performed by the senior author at a single institution are summarized. This cohort has been characterized by brief post-operative length of stay, low complication profile, and marked improvement in patient-reported outcomes scores, with no cases of pseudarthrosis at 1-year follow up.

CONCLUSIONS

The latest technical considerations and adaptations of a novel technique for endoscopic MIS spinal fusion without general anesthesia are described. A refined surgical technique and anesthetic protocol are presented in detail with recommendations for the successful implementation and performance of the procedure.

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.

Full-Endoscopic Removal of Lumbar Juxtafacet Cysts: A Prospective Multicentric Study

BACKGROUND

Lumbar juxtafacet cysts are benign lesions that grow at the level of facet joints or within neighboring structures. Recently, there is an ongoing trend toward less invasive procedures for treating degenerative spine diseases. Here we report a multicenter study of full-endoscopic surgery for juxtafacet cyst removal.

METHODS

We prospectively collected patients with a diagnosis of lumbar juxtafacet cyst surgically treated in 3 institutions between January 2017 and August 2019. Patients of any sex and age were eligible if they had a single level unilateral lumbar juxtafacet cyst, invalidating radicular pain lasting >6 weeks, adequate imaging, and failed percutaneous or conservative treatment. Age at diagnosis; sex; preoperative, postoperative, and 6-month leg pain; surgical and medical complications; spine instability (preoperatively and at 6 and 12 months); and follow-up time were collected.

RESULTS

Thirty-five patients were enrolled. Median operative time was 78 minutes, and mean leg pain went from a preoperative value of 6.8 (standard deviation [SD] = 1.2) to a postoperative value of 3.4 (SD = 1.1, P < 0.001) to 2.1 (SD = 1.7, P < 0.001) at 6 months. At a median follow-up of 15 months, approximately 89% of patients were pain-free or improved. We had 2 recurrences of radicular pain, treated conservatively. Only 2 surgical complications (6%) occurred: 2 small dural tears, both resolved without further intervention.

CONCLUSIONS

Full-endoscopic surgery is feasible and safe for juxtafacet cyst removal. Our results are consistent with findings from recent full-endoscopic and series, with outcomes overlapping those reported for open or tubular techniques.

International Society for the Advancement of Spine Surgery Policy 2019-Surgical Treatment of Lumbar Disc Herniation with Radiculopathy

Lumbar disc herniation (LDH) is a frequent cause of low back pain and radiculopathy, disability, and diminution in quality of life. While nonsurgical care remains the mainstay of initial treatment, symptoms that persist for prolonged periods of time are well treated with discectomy surgery. A large body of evidence shows that, in patients with unremitting symptoms despite a reasonable period of nonsurgical treatment, discectomy surgery is safe and efficacious. In patients with symptoms lasting greater than 6 weeks, various forms of discectomy (open, microtubular, and endoscopic) are superior to continued nonsurgical treatment. The small but significant proportion of patients with recurrent disc herniation experience less improvement overall than patients who do not experience reherniation after primary discectomy. Lumbar discectomy patients with large annular defects (≥6 mm wide) are at a higher risk for recurrent herniation and revision surgery. Annular closure via a bone-anchored device has been shown to decrease the rate of recurrent disc herniation and associated reoperation in these high-risk patients. After a detailed review of the literature, current clinical evidence supports discectomy (open, microtubular, or endoscopic discectomy) as a medically necessary procedure for the treatment of LDH with radiculopathy in indicated patients. Furthermore, there is new scientific evidence that supports the use of bone-anchored annular closure in patients with large annular defects, who are at greater risk for recurrent disc herniation.

Virtual reality in spinal endoscopy: a paradigm shift in education to support spine surgeons

Background

Minimally invasive spine surgery (MISS) and endoscopic spine surgery have continually evolving indications in the cervical, thoracic, and lumbar spine. Endoscopic spine surgery entails treatment of disc disease, stenosis, spondylolisthesis, radiculopathy, and deformity. MISS involves complex motor skills in regions of variable anatomy. Simulator use has been proposed to aid in training and skill retention, preoperative planning, and intraoperative use.

Methods

A systematic review of five databases was performed for publications pertaining to the use of virtual (VR), augmented (AR), and mixed (MR) reality in MISS and spinal endoscopic surgery. Qualitative data analysis was undertaken with focus of study design, quality, and reported outcomes. Study quality was assessed using the Medical Education Research Quality Instrument (MERSQI) score and level of evidence (LoE) by a modified Oxford Centre for Evidence-Based Medicine (OCEBM) level for simulation in medicine.

Results

Thirty-eight studies were retained for data collection. Studies were of intervention-control, clinical application, and pilot or cross-sectional design. Identified articles illustrated use of VR, AR, and MR in all study designs. Procedures included pedicle cannulation and screw insertion, vertebroplasty, kyphoplasty, percutaneous transforaminal endoscopic discectomy (PTED), lumbar puncture and facet injection, transvertebral anterior cervical foraminotomy (TVACF) and posterior cervical laminoforaminotomy. Overall MERSQI score was low-to-medium [M =9.71 (SD =2.60); range, 4.5-13.5], and LoE was predominantly low given the number of purely descriptive articles, or low-quality randomized studies.

Conclusions

The current scope of VR, AR, and MR surgical simulators in MISS and spinal endoscopic surgery was described. Studies demonstrate improvement in technical skill and patient outcomes in short term follow-up. Despite this, overall study quality and levels of evidence remain low. Cohesive study design and reporting with focus on transfer validity in training scenarios, and patient derived outcome measures in clinical studies are required to further advance the field.

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.

Five-year clinical outcomes with endoscopic transforaminal outside-in foraminoplasty techniques for symptomatic degenerative conditions of the lumbar spine

Background

Lumbar foraminal stenosis in the extraforaminal zone is best directly visualized with the outside-in transforaminal endoscopic technique. Stenosis in that area is often missed with traditional translaminar surgery. The authors analyzed the long-term 5-year clinical results, reoperation rates, and unintended after care with the outside-in endoscopic transforaminal foraminoplasty for symptoms from lumbar foraminal stenosis to better establish clinical indications and prognosticators of favorable outcomes.

Methods

Long-term 5-year Macnab outcomes, visual analog scale (VAS) scores, complications, and unintended aftercare were analyzed in a series of 90 patients treated with the transforaminal outside-in selective endoscopic discectomy (SED™) with foraminoplasty for foraminal and lateral recess stenosis.

Results

At minimum 5-year follow-up, excellent results according to the Macnab criteria were obtained in 61 (67.8%) patients, good in 23 (25.6%), fair in 6 (6.7%), respectively. The mean preoperative VAS 7.55. The mean postoperative VAS was 2.87 and at last follow-up 2.53. Both postoperative VAS and last follow-up VAS were statistically reduced at a significance level of P<0.0001. Postoperative dysesthesia occurred in 8 patients (8.9%). While most of the 32 follow-up surgeries following SED™ were additional endoscopic decompressions and rhizotomies (24/32; 75%) were non-fusion procedures, only 8 of the whole study series of 90 patients (8.9%) underwent fusion at the index SED™ level within the minimum 5-year follow-up period. One patient opted for an open laminectomy (1.1%).

Conclusions

Patients with symptomatic foraminal stenosis may be treated successfully in a staged manner with outside-in transforaminal endoscopic decompression while maintaining favorable long-term outcomes without the excessive need for fusion in the vast majority of patients. The reoperation fusion rate at 5-year follow-up was approximately 3 times lower when compared to recently reported reoperation rates following traditional translaminar decompression/fusion.

Internet of Things, Digital Biomarker, and Artificial Intelligence in Spine: Current and Future Perspectives

Recent interest in medical artificial intelligence (AI) has increased with onset of the fourth industrial revolution. Real-time monitoring of patients is an important research area of medical AI. The medical AI is very closely related to the Internet of Things (IoT), a core element of the fourth industrial revolution. Attempts to diagnose and treat patients using IoT have been already applied to patients with chronic disease such as hypertension and arrhythmia. However, in the spine, research on IoT and digital biomarkers are still in the early stages. The digital biomarker obtained by IoT devices is objective and could represent real-time, real-world, and abundant data. Based on its characteristics, IoT and digital biomarkers can also be useful in the spine. Currently, research on real-time monitoring of physical activity or spinal posture is ongoing. Therefore, the authors introduce the basic concepts of IoT and digital biomarkers, their relationship to AI, and recent trends. Current and future perspectives of IoT and digital biomarker in spine are also discussed. In the future, it is expected that IoT, digital biomarkers, and AI will lead to a paradigm shift in the diagnosis and treatment of spinal diseases.

Radiographic and clinical outcomes of huge lumbar disc herniations treated by transforaminal endoscopic discectomy

OBJECTIVES

Large Central disc herniations (occupying more than 50% of canal area) are notorious as they are generally associated with worse outcomes and are technically difficult to manage. Transforaminal endoscopy (TELD) has evolved to become an interesting alternative for lumbar disc herniations. The aim of the paper is to review our technique of transforaminal endoscopy in large central disc herniations and describe the clinical and radiographic results. We also describe an innovative technique of intraoperative epidurography to assess the adequacy of decompression in some cases with severe canal compromise.

PATIENTS AND METHODS

We performed a retrospective analysis of all the patients undergoing TELD from December 2012 to October 2018 for huge central lumbar disc herniations. The procedure was done under local anaesthesia and required a more horizontal approach angle, undercutting of superior articular process and posterior annular release to reach the herniated fragment in the epidural space. In severe cases, a radiopaque dye was introduced via trans-sacral catheter to check the adequacy of decompression. The disc height, lumbar lordosis, segmental lordotic angle on standing radiographs and Canal cross sectional area(CSA) on MRI were evaluated preoperatively and compared with postoperative images at the end of 1 year/final follow-up. The Visual analogue scale(VAS) for Back and Leg pain and Oswestry disability index (ODI), MacNab criteria, return to daily activities, return to work, patient satisfaction rate and recommendation to others were the clinical outcomes evaluated. The percentage of patients achieving the Minimal clinically important difference (MCID) of 3 points for VAS and 12 points for ODI was calculated.

RESULTS

A total of 18 patients, with an average age of 35.1years (range 20-61), were operated. The mean VAS back improved from 5.7(±1.77) to 1(±0.77) and VAS leg improved from 7.3(±1.37) to 1.1(±1.09). The ODI improved from 49.88(±11.42) to 13.88(±7.28) at final follow-up. According to MacNab criteria, 17 patients had excellent and 1 had good outcome at final follow-up. The patient satisfaction rate was 90.5%, with 94% patient recommendation rate. All the patients returned to daily activities and work/modified work within a median of 5 weeks. There was 1 patient who required conversion to open surgery due to incidental dural tear, 1 patient who had a remnant disc required a revision tubular discectomy and 1 patient who had recurrence at 6 weeks and again at 2 years which was treated by repeat TELD. Five patients had impending cauda equina. All the patients achieved the MCID for VAS and ODI within a median period of 6 weeks and 3 months, respectively. The recovery rate was 90.1%. Five patients had grade 4 weakness of great toe/ankle dorsiflexion, one also had ankle flexion weakness preoperatively which improved after surgery. The CSA improved from a preoperative mean of 62.26(±30.3)mm² to 122.16(±56.5)mm² postoperatively. The CSA improved to 141.05(±63.86)mm² at 1 year followup. The average disc height which was 9.71 mm(±2.4) was maintained at follow-up of one year which was 9.21 mm(±2.4). The lumbar lordosis and segmental lordotic angle changed from 27.08°(±15.9) and 2.82°(±5.7) to 35.8°(±8.56) and 4.85°(±4.39) respectively.

CONCLUSION

TELD may be considered as an alternative to microdiscectomy or fusion procedures for huge central disc herniations with favourable outcomes. However, sufficient expertise with the procedure is necessary. Intraoperative decompression may be confirmed with intraoperative epidurography. The patient acceptability of the procedure is good and causes minimal disruption of the normal anatomy.