Full endoscopic contralateral transforaminal discectomy for distally migrated lumbar disc herniation

The Biomechanics of the Transpedicular Endoscopic Approach

STUDY DESIGN

Biomechanical cadaveric study.

OBJECTIVE

The goal of this study was to analyze the effects of an endoscopic transpedicular approach with different drill diameters (6 and 8 mm) and compare them with the intact native side. In addition, the influence of bone quality on the resistance of the pedicle was investigated.

SUMMARY OF BACKGROUND DATA

Clinical studies have repeatedly highlighted the benefits of endoscopic transpedicular decompression for downmigrated lumbar disc herniations. However, the biomechanical effects on pedicle stability have not been studied up to now.

MATERIALS AND METHODS

Twenty-four vertebras originating from four fresh-frozen cadavers were tested under uniaxial compression load in a ramp-to-failure test: (1) the tunneled pedicle on one side, and (2) the native pedicle on the other side. Twelve lumbar vertebrae were assigned to drill diameter of 6 mm and the other 12 to diameter of 8 mm.

RESULTS

The median ratio of sustained force for the operated side compared with the intact contralateral side is equal to 74% (63-88) for both drill diameters combined. An 8 mm transpedicular approach recorded an axial resistance of 77% (60-88) compared with the intact contralateral side ( P =0.002). A 6 mm approach resulted in an axial resistance of 72% (66-84) compared with the intact opposite side ( P =0.01). No significant difference between the two different drill diameters was recorded ( P =1). For all three subgroups (intact, 8 mm, 6 mm) the Hounsfield units-values and the absolute resistance force showed significant correlations (intact: ρ=0.859; P <0.001; 8 mm: ρ=0.902; P <0.001; 6 mm: ρ=0.835; P <0.001).

CONCLUSION

The transpedicular approach significantly reduces the axial resistance force of the pedicle, which may lead to pedicle fracture. Bone quality correlated positively with the absolute resistance force of the pedicle, whereas the influence of the drill hole diameter plays only a limited role.

Finite element mechanical analysis of ipsilateral approach and contralateral approach in unilateral bilateral endoscopic spine surgery

BACKGROUND

Unilateral bilateral endoscopic spine surgery (UBE) is often performed to treat lumbar spinal stenosis and disc herniation. It has become a prominent method in endoscopic spine surgery because of its very low learning curve and broader operative field of vision. Currently, the ipsilateral approach and contralateral approach have been established for disc herniation in the foraminal area, intervertebral foramen region, or pedicle region. The contralateral method offers many benefits over the ipsilateral approach, including less bone labour during microsurgical decompression and the preservation of facet joints. However, because it uses the interlaminar window approach, it inevitably involves osteotomy of the patient's superior and inferior articular processes, which may result in corresponding deterioration in the spine's biomechanical stability and subsequent adjacent facet joint diseases caused by facet joint degeneration postoperatively.

OBJECTIVE

As a result, the purpose of this work is to use a finite element model to evaluate how the ipsilateral approach and contralateral approach in unilateral bilateral endoscopic spine surgery affect spinal stability while treating identical intervertebral disc herniation.

STUDY DESIGN

In this study, a three-dimensional lumbar-sacral spine model was built and verified. Osteotomies were conducted for armpit-type lumbar disc herniation (LDH), periradicular-type LDH, and shoulder-type LDH. Postoperative lumbar spine models of the ipsilateral approach and contralateral approach in unilateral bilateral endoscopic spine surgery were developed. The von Mises stress on the endplate, shear force on the annulus fibrosus, pressure inside the intervertebral disc, and range of motion (ROM) of the L3 segment were all determined. The results of our well-validated model showed that osteotomy done in the ipsilateral approach deteriorated most biomechanical metrics.

RESULTS

In the majority of loading conditions, the contralateral approach caused the intervertebral disc's biomechanical properties to increase, and the ipsilateral approach caused the intervertebral disc's biomechanical properties to increase sharply more than the contralateral approach.

CONCLUSION

The contralateral approach, which is now extensively employed in unilateral bilateral endoscopic spine surgery, may be regarded as an ideal surgical alternative for treating lumbar disc herniation without producing iatrogenic instability. This approach has a low facet joint reduction rate, minimum soft tissue injury, and precisely identifies the midline of the central spinal canal during the retraction of the thecal sac and nerve roots.

Bilateral Transfer of a Visuomotor Task in Different Workspace Configurations

Bilateral transfer occurs when a learned behavior transfers from one (group of) effectors(s) to another. Researchers investigating bilateral transfer of a visuomotor adaptation task between limbs used across workspaces have observed divergent results. This study assessed whether bilateral transfer of a visuomotor adaptation task changes with workspace configuration manipulation. Ninety-six right-handed young adults were assigned to one of three workspace locations, i.e., ipsilateral, contralateral, and central. Within each workspace were two retention groups (RRR/LLL) and two bilateral transfer groups (RLR/LRL). Performance before and after training was collected to determine direct and after-effects. We observed an asymmetric transfer of pathlength (left to right) but no ensuing after-effect. However, the transfer of movement time and normalized jerk was symmetric in the contralateral workspace. These findings showed differences in the pattern of bilateral transfer asymmetry in the different workspace configurations, which was parameter specific.

Clinical Outcomes of Percutaneous Endoscopic Interlaminar Discectomy Using a Laminotomy Technique With Modified Stepwise Local Anesthesia

BACKGROUND

Percutaneous endoscopic interlaminar discectomy (PEID) has been widely used in minimally invasive treatment of lumbar disc herniation (LDH) but is difficult to perform because of the narrow interlaminar window and painful for the patient. Therefore, further research is needed to find a safe and effective method to facilitate the development of PEID.

METHODS

Seventy-one consecutive patients with LDH who underwent PEID using a laminotomy technique with modified stepwise local anesthesia between July 2017 and June 2020. All patients were followed up for at least 6 months. Preoperative patient demographics, perioperative outcomes, and clinical outcomes were recorded. Visual Analog Scale (VAS) scores, Oswestry Disability Index (ODI) scores, and Macnab criteria were used to assess clinical results.

RESULTS

All patients underwent successful surgery under local anesthesia with no conversions to open surgery. The mean operation time was 79.56 ± 32.78 minutes and the average hospital stay was 6.44 ± 2.98 nights. Before surgery, the mean VAS score was 5.66 ± 1.206 and the mean ODI score was 68.41 ± 6.634; the respective scores were decreased to 0.65 ± 0.635 and 7.06 ± 1.594 after 4 weeks of follow-up (P < 0.001) and to 0.56 ± 0.691 and 7.11 ± 0.176 after 6 months (P < 0.001). According to the MacNab criteria, the outcome was excellent in 60 cases and good in the remaining 11 cases.

CONCLUSIONS

PEID via a laminotomy technique with stepwise local anesthesia is safe and effective for L4-5 and L5-S1 LDH.

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.

The 20 most important questions for novices of full-endoscopic spinal surgery in China: a mixed-method study protocol

INTRODUCTION

The full-endoscopic spinal surgery (FESS) procedure is widely accepted and welcomed in China. With the continuous development of minimally invasive surgery, the further expansion of indications and the greater diversity of techniques, spinal endoscopic surgery currently accounts for more than 10% of spinal surgery in China, ranking among the top in the world. However, the admission system and standardised training system for spinal endoscopic surgery are not perfect, which presents a challenge and disadvantage for novices.

METHODS AND ANALYSIS

Exploratory mixed methods are applied for designing this study. First, we will collect questions from novices by allowing them to openly list their concerns to those who have completed FESS. These qualitative questions will be categorised using NVivo software. To produce the qualitative results, a questionnaire for the sequential two-round Delphi approach will be developed to identify the 20 most important questions from novices. This study is planned to be started at April 2021, and completed at March 2022.

ETHICS AND DISSEMINATION

The Research Ethics Committee of Peking University Third Hospital provided a waiver for this Delphi protocol. We expect that the findings will be published in a clinical journal and presented at conferences. Furthermore, we hope that the results can contribute to answering the questions raised by novices of spinal endoscopy in the form of books and to improving the training system for spinal endoscopy surgery.

Functional outcomes of full-endoscopic spine surgery for high-grade migrated lumbar disc herniation: a prospective registry-based cohort study with more than 5 years of follow-up

BACKGROUND

Full-endoscopic lumbar discectomy (FELD) is an alternative to posterior open surgery to treat a high-grade migrated herniated disc. However, because of the complexity of the surgery, success is dependent on the surgeon's skill. Therefore, patients are frequently treated using open discectomy. Anatomical constraints and technical difficulties can lead to the incomplete removal of high-grade migrated discs.

METHODS

We retrospectively reviewed patients who had undergone FELD performed by a single surgeon between January 2010 and January 2014 from a prospective spine registry in an institute. Perioperative records and data of the Oswestry Disability Index, visual analog scale scores (preoperatively and 2 weeks, 6 weeks, 3 months, 6 months, 1 year, 2 years, and 5 years after the operation), and MacNab criteria were collected.

RESULTS

Of 58 patients with a follow-up duration of > 5 years, (41 and 17 patients had undergone transforaminal endoscopic lumbar discectomy [TELD] and interlaminar endoscopic lumbar discectomy [IELD], respectively), the satisfaction rate was 87.8% (five unsatisfactory cases) for TELD and 100% for IELD. The overall percentage of patients with good to excellent results according to modified MacNab criteria was 91.3% (53/58 patients). Two patients had residual discs. Two patients needed an open discectomy due to recurrent disc herniation. One IELD patient received spinal fusion surgery due to segmental instability after 5 years.

CONCLUSION

FELD has a high success rate for the management of high-grade migrated herniated discs. In patients with high-grade disc migration from L1 to L5, TELD is effective and safe. However, for L4-L5 and L5-S1 high-grade upward and downward disc migration, IELD is the favorable option and provides high patient satisfaction.

Transpedicular endoscopic removal of highly migrated disc herniations of lumbar spine

Background. Highly migrated disc herniations are usually localized in the area of pars interarticularis medially to the vertebral pedicle. Removal of disk herniations of this localization is a difficult technical task.

The study objective is to demonstrate the effectiveness of the transpedicular endoscopic discectomy in the treatment of patients with highly migrated disc herniations.

Materials and methods. The results of treatment of 12 patients with Macnab zone herniations who were in hospital from 2016 to 2018 were analyzed. All patients underwent transpedicular endoscopic sequestrectomy.

Results. Leg pain after surgery regressed in all patients from the initial 7.41 points (visual-analog scale) to 0.67 points by the end of the 1st day, and it was 0.35 points a year later. The average level of back pain by VAS before surgery was 5.25, on the 1st day after surgery – 1.25 points, 1 year after – 0.67 points. Neurological disorders completely regressed in 10 (91.6 %) patients, there were a slight residual L4 dermatome hypesthesia in 2 patients, without disrupting their quality of life. The average Oswestry Disability Index before surgery was 69.17, and 1 year after surgery was 14.12. There were no complications and reoperations.

Conclusion. Transpedicular endoscopic discectomy allowed us to achieve good treatment results in patients with migration of a lumbar hernia by the pedicle. It can be a safe and effective alternative to the transforaminal or interlaminar endoscopic technique.

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.

Contralateral Keyhole Biportal Endoscopic Surgery for Ruptured Lumbar Herniated Disc: A Technical Feasibility and Early Clinical Outcomes

OBJECTIVE

Spinal endoscopic surgery is increasingly adapted as a minimal invasive technique, however, significant facet joint violation may be developed after ipsilateral laminectomy. The aim of this study is to introduce surgical technique of contralateral keyhole biportal endoscopic surgery (CKES) for ruptured lumbar disc and report it is early surgical outcomes with facet joint violation.

METHODS

Between January to December 2019, 27 patients with ruptured lumbar disc were underwent CKES. Simple radiographs were obtained to investigate development of iatrogenic instability or spondylolisthesis. Magnetic resonance imaging scan was checked about 8 hours after surgery to evaluate successful removal of ruptured disc and existence of facet joint violation. Clinical outcomes were assessed by modified MacNab criteria, visual analogue scale (VAS) scores of back and radicular pain.

RESULTS

The mean age of the patients was 62.8 ± 12.48 years. The average operative time and mean follow-up period were 57.1 ± 21.36 minutes and 8.1 ± 3.78 months, respectively. Compared to preoperative scores, the VAS scores of back and radicular pain were significantly improved. Modified MacNab outcome grade was good to excellent in 96.3% (26 out of 27 patients) of patients. The reduction rate of facet joint plane was about 4.9% after contralateral approach.

CONCLUSION

CKES may be considered as an excellent surgical option to treat ruptured lumbar disc without the development of iatrogenic instability. Low rate of facet joint reduction, good visualization of lateral recess, and identification of accurate midline of central spinal canal are advantages of the procedure.

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.

Full-Endoscopic Lumbar Foraminoplasty for Symptomatic Cement Leakage with Exiting Nerve Root Impingement

BACKGROUND

Foraminal stenosis, a common disorder occurring in elderly patients, is often caused by narrowing of the foramen, resulting in the confinement of neural structures by the tissue and vertebrae. Full-endoscopic lumbar foraminoplasty (FELF) is an effective treatment option for patients with foraminal stenosis. However, to the best of our knowledge, no previous study has reported the treatment of symptomatic cement leakage. We report a case of symptomatic cement leakage treated with FELF with the patient under local anesthesia.

CASE DESCRIPTION

An 85-year-old woman was admitted to our spine unit because of lower back pain. The patient had presented with lower back pain and new-onset left thigh pain after vertebroplasty performed 3 months previously. The patient was not able to walk and was bedridden. To overcome this problem, T12 percutaneous vertebroplasty and left transforaminal L3-L4 foraminoplasty was performed with the patient under local anesthesia. After surgery, the patient was able to walk and was discharged 4 days postoperatively.

CONCLUSION

The present report has shown that FELF can successfully remove symptomatic cement leakage, resulting in pain relief.

Percutaneous endoscopic lumbar discectomy for LDH via a transforaminal approach versus an interlaminar approach: a meta-analysis

PURPOSE

The aim of this study was to systematically compare the safety and effectiveness of percutaneous endoscopic transforaminal discectomy (PETD) versus percutaneous endoscopic interlaminar discectomy (PEID) for the treatment of lumbar disc herniation (LDH).

MATERIAL AND METHODS

All studies that were performed to compare PETD with PEID to treat LDH and published until 31 August 2017 were acquired through a comprehensive search in various databases. A meta-analysis was performed using the Cochrane Collaboration's RevMan 5.3 software.

RESULTS

A total of 13 trials with 974 cases consisting of 3 randomized controlled trials, 3 prospective studies and 7 retrospective studies were included. The results suggest that patients treated with PEID experienced more significant advantages with shorter operation time, less intraoperative blood loss and less intraoperative fluoroscopy times but more complications than those treated with PETD; however, the two operative approaches did not significantly differ in terms of LDH recurrence, hospital stay, Oswestry disability index (ODI) scores, visual analogue scale (VAS) scores, Japanese Orthopaedic Association (JOA) scores and MacNab criteria at the final follow-up.

CONCLUSION

Based on the results of this study, although PEID may be superior to PETD in certain ways, some of its advantages have yet to be verified and the two interventions were not significantly different in terms of relief of symptoms and functional recovery. Therefore, PEID would be recommended for treating LDH especially at L5/S1 under certain conditions but a prudent attitude is necessary to choose between the two operative approaches before a large sample and high quality randomized controlled trials have been performed.

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.

Management of Root-Level Double Crush: Case Report with Technical Notes on Contralateral Interlaminar Foraminotomy with Full Endoscopic Uniportal Approach

BACKGROUND

Double crush of a nerve at the root level is not common. We describe here a double crush of the right L4 nerve with foramina to far lateral disk (ventral) and extraforaminal (dorsal) compression. The double crush was managed by endoscopy with a contralateral uniportal approach from the left interlaminar space. Right lateral recess stenosis at the same level was subsequently managed with the same approach.

CASE DESCRIPTION

A 79-year-old lady presented to our clinic with a low backache, right leg pain, and weakness. On her right side, the straight leg raise test was 70 degrees, great toe dorsiflexion was grade 3/5, and hypoesthesia was present in the L4 dermatome. Her preoperative visual analog scale score was 9. Magnetic resonance imaging showed right lateral recess stenosis and a double compression of L4 nerve root from the dorsal and ventral sides. A diagnosis of right lateral recess stenosis with double crush of the right L4 nerve root was made. The patient was managed with percutaneous endoscopic contralateral interlaminar foraminotomy from the left interlaminar approach. She got relief for the symptoms and her postoperative visual analog scale score was 2. Magnetic resonance imaging and computed tomography showed nerve root decompression and well-preserved facet joints.

CONCLUSIONS

We conclude that the management of double crush at the nerve root level with interlaminar contralateral approach endoscopy (percutaneous endoscopic contralateral interlaminar foraminotomy) can deal with the issue effectively with facet joint preservation and other benefits of the minimally invasive spine procedure.

[Effect and effectiveness analysis of different approaches of transforaminal endoscope on extirpation amount of nuclues pulposus]

Objective

To investigate the effect and effectiveness analysis of different approaches of transforaminal endoscope on extirpation amount of nuclues pulposus.

Methods

Between August 2011 and December 2014, a total of 165 patients with lumbar disc herniation were retrospectively enrolled and were treated with nucleus pulposus discectomy through transforaminal endoscope. The patients were randomly divided into 4 groups according to different approach of transforaminal endoscope. The posterolateral approach (Yeung's technology) was used in group A (42 cases), transforaminal endoscopic spine system (TESSYS) technology was used in group B (40 cases), improved transforaminal endoscopic access (ITEA) technology was used in group C (43 cases), and interlaminar approach (40 cases) was used in group D (40 cases). There was no significant difference in gender, age, disease duration, symptomatic side, and segments among 4 groups ( P>0.05). The extirpation amount of nuclues pulposus was calculated and compared among 4 groups; the effectiveness was evaluated by pre- and post-operative visual analogue scale (VAS) score, Oswestry disability index (ODI), lumbar curvature index (LCI), and intervertebral height.

Results

The discectomy amount of nucleus pulposus was (3.7±0.8), (3.6±0.7), (4.5±1.1), and (3.0±0.8) cm ³ in groups A, B, C, and D, respectively. The amount of group C was significantly larger than that of the other 3 groups ( P<0.05), and the amount of group D was significantly smaller than that of the other 3 groups ( P<0.05); no significant difference was found between groups A and B ( P>0.05). Cerebrospinal fluid leakage was found in 1 case; no other postoperative complications including intervertebral space infection and epidural hematoma was found. All the incisions healed by first intension. All the patients were followed up 12-24 months (mean, 18 months), and no typical symptoms of recurrence was found during the follow-up period. There was no significant difference in preoperative lower back pain VAS score, lower extremities VAS score, and ODI scores among 4 groups ( P>0.05). The above scores at last follow-up were significantly improved when compared with preoperative ones in each group ( P<0.05), but no significant difference of above scores and recovery values was found among 4 groups ( P>0.05). The difference in LCI and intervertebral height at preoperation and at last follow-up were not significant between 4 groups ( P>0.05). The difference in LCI and intervertebral height of each group between at preoperation and last follow-up were not significant ( P>0.05). And the recovery value of LCI and the lost of height at last follow-up also showed no significant differences between 4 groups ( P>0.05).

Conclusion

The ITEA technology can give a wider field of view than other technologies. It is more convenient to find and remove the nucleus pulposus. However, the appropriate operative approaches should be chosen according to the symptoms and characteristics of lumbar disc herniation.

Effectiveness of Bi-Needle Technique (Hybrid Yeung Endoscopic Spine System/Transforaminal Endoscopic Spine System) for Percutaneous Endoscopic Lumbar Discectomy

OBJECTIVE

The bi-needle technique is a new technique for percutaneous endoscopic lumbar discectomy. This technique combines the advantages of Yeung endoscopic spine system (YESS) and transforaminal endoscopic spine system (TESSYS) techniques. The aim of this study was to evaluate effectiveness of the bi-needle technique for percutaneous endoscopic lumbar discectomy and compare it with the TESSYS technique.

METHODS

We reviewed 86 patients with single-level lumbar disc herniation treated by percutaneous endoscopic lumbar discectomy in our hospital from June 2013 to December 2015. Bi-needle technique was used in 49 patients (30 men, 19 women; average age 40.4 ± 5.2 years). TESSYS technique was used in 37 patients (19 men, 18 women; average age 42.8 ± 6.4 years). Clinical results were evaluated and compared between the 2 groups.

RESULTS

Symptoms in both groups were significantly improved at the last follow-up (P < 0.01). There was no statistical difference in visual analog scale and lumbar Japanese Orthopaedic Association scores between bi-needle and TESSYS groups at last follow-up (P = 0.69 and P = 0.33, respectively). Operative time was shorter in the bi-needle group (P < 0.01). Recurrence rate and reoperation rate were lower in the bi-needle group (P = 0.04 and P = 0.03, respectively). Discitis was diagnosed in 2 patients in the TESSYS group. There were no patients with postoperative discitis in the bi-needle group.

CONCLUSIONS

The bi-needle technique is safe and effective for treatment of lumbar disc herniation. Compared with TESSYS technique, operative time is shorter, and recurrence and reoperation rates are lower.

Percutaneous transforaminal endoscopic discectomy compared with microendoscopic discectomy for lumbar disc herniation: 1-year results of an ongoing randomized controlled trial

OBJECTIVE A prospective randomized controlled study was conducted to clarify whether percutaneous transforaminal endoscopic discectomy (PTED) results in better clinical outcomes and less surgical trauma than microendoscopic discectomy (MED). 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 lumbar disc herniation. Patients were randomly allocated to the PTED or the MED group by computer-generated randomization codes. The primary outcome was the Oswestry Disability Index (ODI) score 1 year after surgery. Secondary outcomes included scores of the Medical Outcomes Study 36-Item Short-Form Health Survey bodily pain and physical function scales, EuroQol Group's EQ-5D , and the visual analog scales for back pain and leg pain. Data including duration of operation, in-bed time, length of hospital stay, surgical cost and total hospital cost, complications, and reoperations were recorded. RESULTS A total of 153 participants were randomly assigned to 2 treatment groups (PTED vs MED), and 89.5% (137 patients) completed 1 year of follow-up. Primary and secondary outcomes did not differ significantly between the treatment groups at each prespecified follow-up point (p > 0.05). For PTED, there was less postoperative improvement in ODI score in the median herniation subgroup at 1 week (p = 0.027), 3 months (p = 0.013), 6 months (p = 0.027), and 1 year (p = 0.028) compared with the paramedian subgroup. For MED, there was significantly less improvement in ODI score at 3 months (p = 0.008), 6 months (p = 0.028), and 1 year (p = 0.028) in the far-lateral herniation subgroup compared with the paramedian subgroup. The total complication rate over the course of 1 year was 13.75% in the PTED group and 16.44% in the MED group (p = 0.642). Five patients (6.25%) in the PTED group and 3 patients (4.11%) in the MED group suffered from residue/recurrence of herniation, for which reoperation was required. CONCLUSIONS Over the 1-year follow-up period, PTED did not show superior clinical outcomes and did not seem to be a safer procedure for patients with lumbar disc herniation compared with MED. PTED had inferior results for median disc herniation, whereas MED did not seem to be the best treatment option for far-lateral disc herniation. Clinical trial registration no.: NCT01997086 (clinicaltrials.gov).

Comparison of the effects of local anesthesia and epidural anesthesia for percutaneous transforaminal endoscopic discectomy in elderly patients over 65 years old

BACKGROUND

Local anesthesia (LA) is recommended for percutaneous transforaminal endoscopic discectomy (PTED) but clinical practice indicates that LA cannot achieve satisfactory pain management during PTED.

OBJECTIVES

The study aimed to investigate the comparisons between LA and EA for PTED in elderly population over 65 years old.

METHODS

We performed a retrospective analysis of patients over 65 years old received PTED from May 2013 to December 2014. And patients were divided into two groups according to the anesthesia method. The data collected for analysis including operative time, fluoroscopy time, postoperative bed time, visual analog scale (VAS), Oswestry Back Pain Disability Index (ODI), the global outcome based on the Macnab outcome criteria, satisfaction rate of anesthesia, and complications.

RESULTS

A total of 132 consecutive patients were enrolled in this study. There were 65 patients in LA group and 67 patients in EA group. Compared to LA group, EA group had longer operative time (P < 0.001) and postoperative bed time (P < 0.001) but shorter fluoroscopy time, (P < 0.001), smaller VAS score of lumbar pain intraoperatively (P < 0.001), 1-h postoperatively (P < 0.001) and 1-week postoperatively (P < 0.001). Similarly, EA group had lower VAS score of leg pain intraoperatively (P < 0.001) and 1-h postoperatively (P < 0.001). In additions, higher satisfaction rate of anesthesia was observed in EA group (P = 0.029).

CONCLUSIONS

EA and LA for PTED achieved comparable clinical outcomes in elderly population over 65 years old. However, compared to LA for PTED, EA had a better performance in pain management.

Grading system for migrated lumbar disc herniation on sagittal magnetic resonance imaging: an agreement study

PURPOSE

Migrated lumbar disc herniations (LDHs) in the sagittal plane are common. Disc migration grading can be applied as a useful measurement tool in the diagnosis, treatment, and outcome evaluation of migrated LDH. No study has evaluated the reliability of migrated LDH grading. We evaluated the reliability and functionality of the current magnetic resonance imaging (MRI) grading system for migrated LDH.

METHODS

We assessed a six-level grading system developed based on sagittal MRI and graded according to the direction (rostral and caudal) and degree (low, high, and very high) of disc migration. One-hundred and one migrated LDHs treated with minimally invasive endoscopic discectomy were analyzed independently by two experienced radiologists. Intraobserver and interobserver agreements were assessed by kappa statistics.

RESULTS

The most common migrated LDH grade was grade 4 (30.94%; caudal, low-grade migration). Rostral and caudal migrations were more common in the upper and lower lumbar levels, respectively. Interobserver agreement in the grading of migrated LDH was good at both the first (kappa = 0.737) and second assessment (kappa = 0.657). The intraobserver agreement for reader 1 was very good (kappa = 0.827) and for reader 2 was good (kappa = 0.620).

CONCLUSIONS

The current grading system for migrated LDH was found to be reliable and functional with good interobserver and intraobserver agreement. It may be useful in the interpretation of disc migration patterns and outcomes of various minimally invasive surgical procedures.

Eccentric technique for foraminoplasty in percutaneous endoscopic transforaminal procedure: A technical note

OBJECTIVE

To describe a modified technique usied for foraminoplasty in percutaneous endoscopic transforaminal procedure.

METHODS

58 patients (20 males and 38 females, average age 52.5 years) underwent percutaneous endoscopic transforaminal procedure by using our modified technique. Under the guidance of C-arm fluoroscopy, a kirschner wire was inserted into targeted superior articular process. After expanding the soft tissues, a trepan with the largest diameter was located through the kirschner wire and the angle of trepan was flexible enough to adjust to different operative conditions. This technique could help to avoided using step-by-step larger diameters of trepans without slippage during foraminoplasty.

RESULTS

With our modified technique, the mean operation time was 65 min (range 50-80 min) and mean estimated blood loss was 12 ml (range 10-30 ml). Fluoroscopy was less (the mean duration of fluoroscopy was 20.4 ± 9.2 s and the mean radiation dose was 0.9 ± 0.2 mSv) and no complications occurred. All foraminoplasties were excellent via CT scans after surgery and all patients were discharged on 2nd day after operation. The results of 58 patients with an average follow-up of 18 (6-36) months demonstrated our eccentric technique to be effective.

CONCLUSION

Our eccentric technique could help to avoid step-by-step larger diameters of trepans during foraminoplasty to shorten operation time and reduced the number of fluoroscopy intraoperative.

Multi-level spine endoscopy: A review of available evidence and case report

In the last ten years, there has been an exponential increase in endoscopic spinal surgery practice.

With improvements in equipment quality and the availability of high definition camera systems, cervical endoscopic disc resection is now a viable alternative to anterior cervical decompression and fusion (ACDF) or disc arthroplasty for the treatment of disc prolapse and low grade stenosis.

Based on the current literature, there is now strong evidence to support the use of transforaminal endoscopic approaches for the treatment of thoracic disc prolapse.

There is now level I evidence to show that outcomes following transforaminal endoscopic discectomy (TED) are at least equivalent to those after open microdiscectomy, with an expected shorter operating time, lesser requirement for analgesia, reduced duration of post-operative disability, more rapid rehabilitation and lower costs of care. However, it should be recognised that there is a significant learning curve for TED.

New endoscopic techniques with interlaminar approaches allow the decompression of central and lateral recess stenosis. Future developments will facilitate vision and access to the spine with 3D imaging and robotics at the forefront.

We present a case report of whole spine endoscopic decompression to illustrate the potential of endoscopic surgery at all spinal levels.

Cite this article: EFORT Open Rev 2017;2:317-323. DOI: 10.1302/2058-5241.2.160087

A Radiographic Measurement of the Anterior Epidural Space at L4-5 Disc Level

To observe the morphology character of the anterior epidural space at the L_4-5 disc level and to provide an anatomical basis for safely and accurately performing a percutaneous endoscopic lumbar discectomy (PELD). Fifty-five cases with L₅ S₁ lumbar disc herniation were included in this study, and cases with L_4-5 disease were excluded. When the puncture needle reached the epidural space at the L₅ S₁ level, iohexol was injected at the pressure of 50 cm H₂ O during the PELD, then C-Arm fluoroscopy was used to obtain standard lumbar frontal and lateral images. The widths of epidural space at the level of the L₄ lower endplate, the L₅ upper endplate, as well as the middle point of the L_4-5 disc were measured from the lumbar lateral X-ray film. Epidural space at the L_4-5 disc plane performs like a trapezium chart with a short side at the head end and a long side at the tail end in the lumbar lateral X-ray radiograph, while the average widths of epidural space were 10.2 ± 2.5, 12.3 ± 2.3, and 13.8 ± 2.6 mm at the upper, middle, and lower level of the L_4-5 disc. Understanding the morphological characteristics of epidural space will contribute to improving the safety of the tranforaminal percutaneous endoscopy technique.

Surgical Outcome of Two-Level Transforaminal Percutaneous Endoscopic Lumbar Discectomy for Far-Migrated Disc Herniation

Objective. To describe the two-level percutaneous endoscopic lumbar discectomy (PELD) technique in transforaminal approach for highly migrated disc herniation and investigate its clinical outcomes. Methods. A total of 22 consecutive patients with highly migrated lumbar disc herniation were enrolled for the study from June 2012 to February 2014. Results. There were 12 males and 10 females, with a mean age of 41.1 (range 23–67) years. The mean follow-up period was 18.05 (range 14–33) months. According to the modified MacNab criteria, the clinical outcome at the final follow-up was excellent in 14, good in 6, and fair in 2 patients and the satisfactory rate (excellent and good) was 90.9%. The improvements in VAS and ODI were statistically significant. One patient had recurrent herniation in 18 months after the first surgery and underwent open discectomy. One patient showed symptoms of postoperative dysesthesia (POD), but the POD symptom was transient and partial remission was achieved in two months after conservative treatment. Conclusion. Two-level PELD in transforaminal approach can be a safe and effective procedure for highly migrated disc herniation.

A randomised controlled trial of transforaminal endoscopic discectomy vs microdiscectomy

PURPOSE

Transforaminal endoscopic discectomy (TED) minimises paraspinal muscle damage. The aim of this trial was to compare clinical outcomes of TED to Microdiscectomy (Micro).

METHODS

143 patients, age 25-70 years and <115 kg, with single level lumbar prolapse and radiculopathy, were recruited and randomised. 70 received TED under conscious sedation and 70 Micro under general anaesthesia. Oswestry Disability Index (ODI), visual analogue scores (VAS) of back and leg pain, and Short Form Health Survey indices (SF-36) were measured preoperatively and at 3, 12 and 24 months.

RESULTS

All outcome measures improved significantly in both groups (p < 0.001). Affected side leg pain was lower in the TED group at 2 years (1.9 ± 2.6 vs 3.5 ± 3.1, p = 0.002). Hospital stay was shorter following TED (0.7 ± 0.7 vs 1.4 ± 1.3 days, p < 0.001). Two Micro patients and five TED patients required revision giving a relative risk of revision for TED of 2.62 (95% CI 0.49-14.0).

CONCLUSIONS

Functional improvements were maintained at 2 years in both groups with less ongoing sciatica after TED. A greater revision rate after TED was offset by a more rapid recovery.

A brief history of endoscopic spine surgery

Few neurosurgeons practicing today have had training in the field of endoscopic spine surgery during residency or fellowship. Nevertheless, over the past 40 years individual spine surgeons from around the world have worked to create a subfield of minimally invasive spine surgery that takes the point of visualization away from the surgeon's eye or the lens of a microscope and puts it directly at the point of spine pathology. What follows is an attempt to describe the story of how endoscopic spine surgery developed and to credit some of those who have been the biggest contributors to its development.

Technical considerations in transforaminal endoscopic spine surgery at the thoracolumbar junction: report of 3 cases

OBJECTIVE In this study the authors describe the technical considerations and feasibility of transforaminal discectomy and foraminoplasty for the treatment of lumbar radiculopathy in patients who have herniated discs at the thoracolumbar junction. METHODS After institutional review board approval, charts from 3 consecutive patients with lumbar radiculopathy and T12-L1 herniated discs who underwent endoscopic procedures between 2006 and 2014 were reviewed. RESULTS Consecutive cases (n = 1316) were reviewed to determine the incidence and success of surgery performed at the T12-L1 level. Only 3 patients (0.23%) treated with endoscopic surgery for their herniated discs had T12-L1 herniated discs; the rest were lumbar or lumbosacral herniations. For patients with T12-L1 disc herniations, the average preoperative visual analog scale score was 8.3 (indicated in the questionnaire as describing severe and constant pain). The average 1-year postoperative visual analog scale score was 1.7 (indicated in the questionnaire as mild and intermittent pain). CONCLUSIONS Transforaminal endoscopic discectomy and foraminotomy can be used as a safe yet minimally invasive technique for the treatment of lumbar radiculopathy in the setting of a thoracolumbar disc herniation.

Transpedicular Lumbar Endoscopic Surgery for Highly Migrated Disk Extrusions: Preliminary Series and Surgical Technique

OBJECTIVE

Endoscopic surgery for highly migrated lumbar disk extrusions is a challenge even for spine surgeons who are familiar with using endoscopic techniques. Because of the anatomic constraints involved in transforaminal access in endoscopic surgery, an incomplete removal of a highly migrated disk extrusion can result in some cases. Here the authors describe a new technique for accessing extruded lumbar disks that have migrated into the canal directly through a transpedicular approach.

METHODS

A technique for the endoscopic treatment of highly migrated lumbar disk extrusions is presented. Retrospectively, we reviewed a series of 21 consecutive patients operated on with lumbar 3-4, lumbar 4-5, and lumbar 5-sacral 1 highly migrated disk extrusions: preoperative and postoperative clinical data with 1-year follow-up.

RESULTS

A preliminary series of 11 male and 10 female patients with an average age of 56.9 years (from 33-78 years old) who underwent transpedicular endoscopic retrieval of an extruded lumbar disk between 2012 and 2015 is presented. Two patients required revision to transforaminal access, 1 at the same sitting and the other 4 weeks later. The mean visual analog scale score for radicular pain improved from an average pain score before surgery of 8.1-1.7 one year after surgery. No pedicle fractures were encountered.

CONCLUSIONS

Transpedicular endoscopic access to highly migrated lumbar herniated disk extrusions is presented as a unique minimally invasive approach to extruded lumbar herniated disks, especially at L3-4, L4-5, and L5-S1.

Transforaminal percutaneous endoscopic lumbar discectomy for very high-grade migrated disc herniation

OBJECTIVES

Transforaminal percutaneous endoscopic lumbar discectomy (PELD) for high-grade migrated disc herniation has been regarded as a challenging task, but because of the remarkable improvement in navigable instruments and advanced epiduroscopic technique, it can be used for the treatment of high- or very high-grade migrated disc herniation. The purpose of this study was to describe in detail the standardized technique of transforaminal PELD for very high-grade migrated disc herniation and demonstrate the clinical results.

METHODS

Very high-grade lumbar migrated disc herniation was defined as a disc migration beyond the inferior margin of the pedicle. Thirteen consecutive patients with very high-grade lumbar migrated disc herniation were treated with transforaminal PELD, which has three stages: (1) direction-oriented transforaminal approach, (2) release of periannular anchorage, and (3) epiduroscopic fragmentectomy with navigable instruments. The surgical outcomes were assessed using the visual analogue pain score (VAS), Oswestry disability index (ODI), and modified Macnab criteria.

RESULTS

The operated levels were L3-4 in 2 (15.4%) patients, L4-5 in 10 (76.9%), and L5-S1 in 1 (7.7%). The directions of migration were cranial in 8 patients and caudal in 5. The mean VAS for leg pain improved from 7.86±1.28 preoperatively to 2.54±1.51 at 6 weeks postoperatively and 1.85±1.07 at 1year postoperatively (P<0.01). The mean preoperative ODI improved from 84.92±6.36 preoperatively to 27.83±7.34 at 6 weeks postoperatively and 17.54±13.40 at 1year postoperatively (P<0.01). Excellent or good global outcomes were obtained in 84.6%, and the rate of symptomatic improvement was 92.3%.

CONCLUSION

Transforaminal PELD can be effective for very high-grade migrated lumbar disc herniation, and a standardized technique may provide a reliable and reproducible result.

Transforaminal Endoscopic Foraminoplasty and Discectomy for the Treatment of a Thoracic Disc Herniation

Transforaminal endoscopic spine surgery has emerged internationally as a minimally invasive technique that can be performed in an awake patient in the outpatient setting. Advances in high-definition endoscopic camera technologies as well as the availability of specialty graspers, reamers, drills, and other instruments that can be used down a working channel endoscope have made a myriad of spine diseases accessible to the minimally invasive spine surgeon. The major challenge inherent in the surgical treatment of thoracic disc disease is that the disc herniation is often ventral to the spinal cord. The transforaminal approach and the angled endoscopic camera are an ideal combination for creating a technical advantage to accessing thoracic disc disease.

Transforaminal endoscopic decompression of a postoperative dislocated bone fragment after a 2-level lumbar total disc replacement: case report

The proposed advantages of total disc replacement (TDR) over fusion in the lumbar spine are the preservation of motion and the avoidance of adjacent-level disease. One of the complications inherent in TDR is the possibility of vertebral body fracture due to trauma or a malpositioned implant. The resulting dilemma is that posterior decompression of the displaced bone fragment could then have a destabilizing effect and possibly require fusion, thus obviating the benefit of an arthroplasty procedure. In this study, the authors describe the technical considerations and feasibility of the treatment of a postoperative L-5 paresis that resulted from a dislocated bone fragment at L4–5 during a 2-level lumbar TDR.

Endoscopic foraminotomy for recurrent lumbar radiculopathy after TLIF: Technical report

Background:

Transforaminal lumbar interbody fusion (TLIF) is a well-accepted fusion technique that uses unilateral facet removal as an oblique corridor for inserting an interbody spacer. This manuscript focused on five cases of endoscopic foraminotomy for patients presenting with recurrent radiculopathy after TLIF procedures.

Methods:

After Institutional Review Board approval, charts from five patients with lumbar radiculopathy and instrumented TLIF procedures who underwent subsequent endoscopic procedures between 2011 and 2013 were reviewed.

Results:

The average pain relief 1 year postoperatively was reported to be 63.8%, good results as defined by MacNab. The average preoperative visual analog scale (VAS) score was 9.5, indicated in our questionnaire as severe and constant pain. The average 1 year postoperative VAS score was 3.5, indicated in our questionnaire as mild and intermittent pain.

Conclusion:

Transforaminal endoscopic discectomy and foraminotomy could be used as a safe, yet, minimally invasive and innovative technique for the treatment of lumbar radiculopathy in the setting of previous instrumented lumbar fusion.

IRB approval:

Lifespan: IRB Study # 600415

The surgical treatment of single level multi-focal subarticular and paracentral and/or far-lateral lumbar disc herniations: the single incision full endoscopic approach

BACKGROUND

Surgery for same level multi-focal extruded lumbar disc herniations is technically challenging and the optimal method controversial. The subarticular disc herniation may pose the most challenging subtype requiring partial or complete facetectomy with or without fusion. The far-lateral disc herniation, often treated using a Wiltse approach, can also be difficult to access especially in the obese patient. When both the subarticular and far-lateral subtypes are simultaneously present at the same level with or without a paracentral disc herniation, a total facetectomy and interbody fusion (TLIF) or a total disc replacement (TDR) may be necessary. Endoscopic surgical techniques may reduce the need for these more invasive methods.

METHODS

Fifteen patients (6 male and 9 female) who had same level multi-focal (subarticular as well as far-lateral and/or paracentral) extruded disc herniations underwent single incision unilateral endoscopic disc excision by the same surgeon at a single institution. Patients were prospectively followed for an average of 15.3 months (range 14-18 months) and outcomes were evaluated radiographically and clinically (Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI).

RESULTS

The mean operative time was 52 minutes with minimal blood loss in all cases. Fourteen of the 15 patients were discharged to home on the day of their surgery. The mean ODI and leg VAS scores improved from 22.9 ± 3.2 to 12.9 ± 2.7 (p < 0.005), and from 8.6 ± 1.6 to 2.1 + 0.4 (p < 0.005), respectively.

CONCLUSIONS

After an average of 15.3 months of follow-up, the clinical and radiographic results of full endoscopic surgical treatment of single level multi-focal (subarticular as well as far-lateral and/or paracentral) disc herniations are excellent. This study is a case series with mid-term follow-up (Level IV).

CLINICAL RELEVANCE

Foraminal and extra-foraminal full endoscopic decompression appears to offer a safe minimally invasive solution to a complex pathologic problem.

Clinical success of transforaminal endoscopic discectomy with foraminotomy: a retrospective evaluation

OBJECTIVE

Transforaminal endoscopic surgery has evolved from an intradiscal procedure to a true foraminal epidural procedure where both a targeted discectomy and foraminal decompression can be performed. The success of transforaminal decompression for radiculopathy using preoperative selective nerve root block as part of a treatment algorithm for single level and multilevel lumbar disc herniations is described here.

METHODS

After Institutional Review Board Approval, charts from 195 patients with complaints of lower back and radicular pain who received one or more endoscopic discectomy procedures were reviewed. Visual Analog Scale was applied to each patient preoperatively and 6 months after the procedure.

RESULTS

Patients with multi-level pathologies receiving one procedure have an average relief of 69.7% attributed to correct diagnosis of the inflicting level as opposed to 83.9% improvement in patients with a single level herniation.

CONCLUSION

Patients with single level lumbar herniations receiving one endoscopic discectomy have excellent outcomes, but with a good response to a selective nerve root block as a preoperative adjunct, patients with multilevel disc herniations also have significant benefit from single level endoscopic discectomy.