Transforaminal endoscopic decompression for radiculopathy secondary to intracanal noncontained lumbar disc herniations: outcome and technique

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

The Utility of Diagnostic Transforaminal Epidural Injection in Selective Percutaneous Endoscopic Lumbar Discectomy for Multilevel Disc Herniation with Monoradicular Symptom: A Prospective Randomized Control Study

BACKGROUND

The aim of this study was to analyze the clinical outcomes of diagnostic transforaminal epidural injection (DTEI) in selective percutaneous endoscopic lumbar discectomy for multilevel disc herniation with monoradicular symptom.

METHODS

A prospective randomized clinical study was performed from November 2013 to January 2018. A total of 99 consecutive patients with multilevel disc herniation and monoradicular symptom were divided randomly into the DTEI (n = 48) or control (n = 51) group based on a random number list. Operation time, blood loss, intraoperative fluoroscopy, and length of hospital stay were recorded and analyzed statistically. Visual analog scale (VAS) scores, Oswestry Disability Index (ODI), and the improved MacNab standard were used to assess the clinical outcomes of the 2 groups.

RESULTS

No differences were observed between the 2 groups in aspect of baseline data. The patients of both groups had significant improvement in VAS and ODI scores compared with preoperative value. However, the postoperative VAS and ODI scores of the DTEI group were significantly lower compared with the control group. The clinical outcomes of the DTEI group according to the improved MacNab standard were significantly better than that of the control group.

CONCLUSIONS

DTEI can improve the clinical outcomes of selective percutaneous endoscopic lumbar discectomy for multilevel disc herniation with monoradicular symptom, through improving the accuracy of confirmation of responsible level.

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

Objective

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

Background

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

Methods

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

Results

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

Conclusions

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

Transforaminal Endoscopic Decompression for Lumbar Lateral Recess Stenosis: An Advanced Surgical Technique and Clinical Outcomes

OBJECTIVE

The clinical application of endoscopic techniques for lumbar lateral recess stenosis (LRS) is still challenging. This study aimed to describe a transforaminal endoscopic decompression (TED) technique for LRS and to demonstrate its clinical results.

METHODS

Two-year follow-up data were collected from 45 consecutive patients who underwent TED for LRS. Full-scale endoscopic decompression was performed in the dorsal and ventral aspects of the lateral recess with combined partial pediculectomy using an articulating bone burr and endoscopic instruments. Surgical outcomes were evaluated using the Visual Analog Pain Score (VAS), Oswestry Disability Index (ODI), and modified Macnab criteria.

RESULTS

The mean age of the 27 female and 18 male patients was 64.9 years. The mean VAS for leg pain and mean ODI improved from 7.93 and 75.87 at baseline to 1.71 and 17.87, respectively, at 2 years after surgery (P < 0.001 and P < 0.001, respectively). Based on the modified Macnab criteria, excellent or good results were obtained in 86.7% of the patients, and symptomatic improvements were obtained in 97.8%. One patient underwent revision surgery because of incomplete decompression, and 2 experienced transient dysesthesia.

CONCLUSION

TED with the patient under local anesthesia can be effective for the treatment of LRS, especially for the elderly or patients at a high risk for general anesthesia.

Expression and Mechanism of Interleukin 1 (IL-1), Interleukin 2 (IL-2), Interleukin 8 (IL-8), BMP, Fibroblast Growth Factor 1 (FGF1), and Insulin-Like Growth Factor (IGF-1) in Lumbar Disc Herniation

BACKGROUND The expression and mechanism of IL-1, IL-2, IL-8, BMP, FGF1, and IGF-1 in Sprague-Dawley (SD) rats with lumbar disc herniation were investigated. MATERIAL AND METHODS Immunohistochemical methods were applied to identify IL-1, IL-2, IL-8, BMP, FGF1, and IGF-1. PI3K, AKT protein, and mRNA expression were detected and analyzed by Western blot analysis. We selected 30 healthy SD rats and divided them into 2 groups to construct an animal model that was validated by immediate CT scanning. Cartilage tissues from the lumbar disc herniation (experimental) group and control group were obtained and compared. RESULTS The expression of BMP was not significantly different between the control group and the experimental group (P>0.05). FGF1: There was no significant difference in the expression of FGF1 (P>0.05) between the control group and the experimental group. Compared with the control group, the expression of IGF-1 in the experimental group was significantly higher (P<0.05); the expression of IL-1 in the experimental group was significantly higher (P<0.05); and the expression of IL-2 in the experimental group was also significantly higher (P<0.05). There was no significant difference in IL-8 between the experimental group and the control group (P>0.05). The expression levels of PI3K and AKT protein and mRNA were significantly higher than those in healthy controls (P<0.05). CONCLUSIONS After lumbar disc herniation occurred, the IGF-1 was first activated; the PI3K/AKT signaling pathway was later activated, which resulted in the expression of IL-1 and IL-2 inflammation-related factors being increased.

Early Clinical Results of Percutaneous Endoscopic Transforaminal Lumbar Interbody Fusion: A New Modified Technique for Treating Degenerative Lumbar Spondylolisthesis

INTRODUCTION

Lumbar interbody fusion is used to treat degenerative lumbar spondylolisthesis with instability. We developed a device that safely expands a percutaneous path through Kambin's triangle and used it via a new technique: percutaneous endoscopic transforaminal lumbar interbody fusion (PETLIF). We report in this study the details and outcomes of this procedure after a one year follow-up.

METHODS

Twenty-five patients requiring interbody fusion for degenerative spondylolisthesis of the L4 vertebra were enrolled in this study. The procedure involved percutaneous posterior pedicle screw placement to correct spondylolisthesis. After the exterior of the L5 vertebra superior articular protrusion was shaved with a percutaneous endoscopic drill in order to expand the safe zone, the oval sleeve was inserted through Kambin's triangle and was rotated to expand the disk height and create a path toward the vertebral disk. The interbody cage was inserted against the J-shaped nerve retractor, with the exiting nerve root retracted. Indirect decompression of spinal canal stenosis was expected because the vertebral body spondylolisthesis had been corrected and the interbody distance was expanded. Thus, no direct decompression was performed posterolaterally.

RESULTS

The mean follow-up period, surgery time, and blood loss were 22.7 months, 125.4 min, and 64.8 mL, respectively. The Japanese Orthopaedic Association score improved from 13.3 to 28.0. The Roland-Morris Disability Questionnaire score improved from 10.3 to 3.3. All items were evaluated both preoperatively and one year postoperatively. Bone fusion was observed one year postoperatively in 22 out of 25 patients.

CONCLUSIONS

These results demonstrate the feasibility and efficacy of PETLIF for treating degenerative lumbar spondylolisthesis. This minimally invasive procedure is useful and has wide applicability. To obtain safe and favorable results, necessary surgical techniques must be mastered, and surgical equipment, including that for neural monitoring, is required.

Intraoperative Disc Prolapse During Percutaneous Endoscopic Lumbar Discectomy

BACKGROUND

Percutaneous endoscopic lumbar discectomy (PELD) is regarded as an alternative treatment for lumbar disc herniation. Although the indication for PELD has expanded with remarkable evolution of the technique, sometimes unexpected complications have occurred during PELD. We report 3 cases of de novo disc prolapse during PELD.

CASE DESCRIPTION

In 3 patients who underwent PELD for lumbar disc herniation with local anesthesia, postoperative magnetic resonance imaging demonstrated newly developed up-migrated disc herniation. Compared with their preoperative states, these patients experienced decreased intensity of both leg and back pain. There were no neurologic deficits. PELD was repeated for L1-L2 disc herniation only to relieve compression of the conus medullaris.

CONCLUSIONS

Although the incidence was very low (0.3%) and the lesions were nonsymptomatic, de novo disc prolapse may be associated with an inside-out PELD technique. Discography and insertion of the obturator should be handled gently. The possibility of de novo disc prolapse should be kept in mind when performing PELD.

Five-year outcomes and predictive factors of transforaminal full-endoscopic lumbar discectomy

Although several studies have reported the effectiveness of transforaminal full-endoscopic lumbar discectomy (TELD), no cohort study on the long-term outcomes of TELD has been conducted. Thus, this study aimed to evaluate the long-term clinical outcomes of TELD and to determine the factors predicting favorable outcome.Five-year longitudinal data of 204 consecutive patients who underwent TELD were collected. Outcomes were assessed using the visual analog scale (VAS) pain score, Oswestry disability index (ODI), patient satisfaction rating, and the modified Macnab criteria.The mean VAS score for leg pain improved from 7.64 at the baseline to 1.71, 0.81, 0.90, and 0.99 at postoperative 6 weeks, 1 year, 2 years, and 5 years, respectively (P <.001). The mean ODI improved from 67.2% at the baseline to 15.7%, 8.5%, 9.4%, and 10.1% at postoperative 6 weeks, 1 year, 2 years, and 5 years, respectively (P <.001). The overall patient satisfaction rate was 94.1%. Based on the modified Macnab criteria, 83.8% of patients had excellent or good results. In this study, younger patients with intracanal disc herniation tended to have better outcomes than elderly patients with foraminal/far-lateral disc herniation (P <.05).Transforaminal endoscopic lumbar discectomy offers favorable long-term outcomes with minimal tissue damage. Postoperative pain and functional status may change over time. Proper patient selection remains essential for the success of this minimally invasive procedure.

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

Background

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

Methods

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

Results

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

Conclusions

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

Endoscopic Transforaminal and Lateral Recess Decompression After Previous Spinal Surgery

Background

Leg pain and back pain after lumbar laminectomy and spinal decompression fusion surgery are common and often related to persistent lumbar foraminal or lateral recess stenosis. Although persistent symptoms often stem from incomplete decompression during the primary index surgery, recurrent symptoms may also be the result of intervertebral cage subsidence due to loss of intervertebral and neuroforaminal height.

Objective

The aim of this study was to investigate the feasibility of using the outpatient transforaminal decompression procedure as an alternative to inpatient open procedure in revision decompression surgery, with the intent of minimizing the incidence of perioperative and postoperative surgical complications while reducing both direct and indirect costs of surgical treatment, shortening time to patient postoperative narcotic independence, and shortening time of patient return to daily activities.

Methods

A total of 48 patients with conclusive diagnostic imaging and interventional workup underwent endoscopic transforaminal and lateral recess decompression for both persistent or recurrent leg and/or low back pain following previous lumbar laminectomy (22 patients) or decompression fusion surgery (26 patients). In addition to radiographic studies, patients were followed for a minimum of 2 years postoperatively, and clinical outcomes were evaluated with the visual analog scale (VAS), Oswestry Disability Index (ODI), and modified Macnab criteria.

Results

At final follow-up, patients with single- and 2-level prior surgeries reported an average ODI reduction following their secondary surgery of 44.6%, with an average final score of 14.8. Less favorable ODI score reductions following secondary surgery (23.8%) were reported by patients who had more than one or a complex prior multilevel surgery. According to the modified Macnab criteria, "excellent" and "good" results were obtained with the secondary surgery in 79.1% (38 of 48) of patients with no more than a single 1- or 2-level prior lumbar surgery. The mean VAS score decreased from 7.7 ± 1.8 preoperatively to 2.3 ± 1.1 at final follow-up (P < .01). Fair and poor results with the secondary surgery were seen in 20.9% (10 of 48) of patients with several prior surgeries or complex multilevel previous lumbar surgeries. The level distribution for secondary surgery was as follows: L4-5 segment (26 levels; 54.1%), L5-S1 (14 levels; 29.2%), L3-4 (7 levels; 14.6%), and the L2-3 level (1 level; 2.1%). Postoperative complications were limited to irritation of the dorsal root ganglion, which occurred in 25% (12 of 48) of patients. There were no wound infections, nerve root injuries, foot drop, or admissions to a hospital for further postoperative care. All patients with "excellent" and "good" outcomes measured by modified Macnab criteria, who were working before and after the primary and secondary surgeries (27 of 38), reported earlier return to work after the endoscopic outpatient surgery (2.6 ± 0.8 weeks) than with the prior inpatient open spinal surgery (8.1 ± 4.5 weeks). Based on the 2012 Medicare fee schedule for professional fees, direct costs were 40.6% and indirect costs were 37.1% lower with the secondary endoscopic surgery compared with primary open surgery.

Conclusions

Transforaminal decompression is an effective alternative to open revision lumbar spinal surgery to treat symptomatic spinal stenosis after previous lumbar surgery in patients with persistent or recurrent leg and low back pain. It can be safely done in an outpatient setting, while realizing savings in direct and indirect costs.

Transforaminal endoscopic discectomy versus conventional microdiscectomy for lumbar discherniation: a systematic review and meta-analysis

BACKGROUND

The open microdiscectomy is the most common surgical procedure for the decompression of radiculopathy caused by lumbar disk herniation. To date, a variety of minimally invasive (MI) techniques have been developed. In the last decades, endoscopic techniques have been developed to perform discectomy. The transforaminal endoscopic discectomy (TED) with posterolateral access evolved out of the development of endoscopic techniques.

METHODS

A systematic literature search was performed using the PubMed, EMBASE, and Cochrane Library databases for trials written in English. The randomized trials and observational studies that met our inclusion criteria were subsequently included. Two reviewers respectively extracted data and estimated the risk of bias. All statistical analyses were performed using Review Manager 5.3.

RESULTS

Five prospective and four retrospective studies involving 1527 patients were included. The results of the meta-analysis indicated that there were significant differences between the two groups in length of hospital stay (MD = - 8.41, 95% CI - 10.26, - 6.56; p value < 0.00001). However, there were no significant differences in the leg visual analog scale (VAS) scores, the Oswestry Disability Index (ODI) scores, and the incidence of complications and recurrence.

CONCLUSIONS

The transforaminal endoscopic discectomy is superior to open microdiscectomy in the length of hospital stay. However, there were no differences in leg pain, functional recovery, and incidence of complications between TED and MD in treating LDH.

A Rare Case of Progressive Palsy of the Lower Leg during Percutaneous Endoscopic Lumbar Discectomy via a Transforaminal Approach

Percutaneous endoscopic discectomy (PED) for lumbar disc herniation is gaining popularity with the transforaminal (TF) approach preferred because it allows surgery under local anesthesia and preserves the spinal muscles. Although this procedure has some characteristic complications, it is rare for PED to be converted to conventional open surgery due to worsening of symptoms intraoperatively. Here, we report PED via the TF approach that required conversion to open surgery. A 20-year-old man with a large disc herniation at L3/4 developed severe progressive leg pain and muscle weakness of the left leg intraoperatively. Magnetic resonance imaging revealed that the size of the herniation was unchanged and the endoscope did not reach the herniated mass. We converted to open surgery, and the patient's postoperative course was favorable. We discuss the reasons for failure of the approach and suggest planning for an appropriate foraminoplasty to avoid the potential need for conversion to open surgery.

Intradiscal Expandable Balloon Distraction During Transforaminal Decompression for Lumbar Foraminal and Lateral Recess Stenosis

Advanced videoendoscopic equipment (such as motorized drills, chisels, and rongeurs) facilitates the use of modern decompression tools through the inner working channel of the spinal endoscope using the transforaminal approach. Postoperative dysesthetic leg pain, however, is common because of irritation of the dorsal root ganglion. This article presents a novel surgical technique employing an expandable balloon placed into the hollow intervertebral space in patients without any functional disc tissue to distract the stenotic motion segment. This approach improves visualization, facilitates removal of bone during the decompression, and minimizes intraoperative manipulation of the exiting and traversing nerve roots. In a study of 52 targeted patients with symptomatic spinal stenosis at 60 levels (L2/3-1, L3/4-9, L4/5-28, and L5/S1-22) due to advanced degenerative changes of the intervertebral disc and facet joint complex contributing to both foraminal and lateral recess stenosis, only 2 of the 52 patients complained of postoperative dysesthetic leg pain (3.85%) after undergoing this novel procedure. At the final 2-year follow-up, 80.9% of patients showed Excellent and Good outcomes according to modified Macnab criteria.

Suprapedicular Circumferential Opening Technique of Percutaneous Endoscopic Transforaminal Lumbar Discectomy for High Grade Inferiorly Migrated Lumbar Disc Herniation

Purpose

To evaluate the efficacy of suprapedicular circumferential opening technique (SCOT) of percutaneous endoscopic transforaminal lumbar discectomy (PETLD) for high grade inferiorly migrated lumbar disc herniation.

Material and Methods

Eighteen consecutive patients who presented with back and leg pain with a single-level high grade inferiorly migrated lumbar disc herniation were included. High grade inferiorly migrated disc was removed by the SCOT through PETLD approach. Outcome evaluation was done with visual analog scale (VAS) and Mac Nab's criteria.

Result

There were 14 males and 4 females. The mean age of patients was 53.3 ± 14.12 years. One, 4, and 13 patients had disc herniation at L1-2, L3-4, and L4-5 levels, respectively, on MRI, which correlated with clinical findings. The mean follow-up duration was 8.4 ± 4.31 months. According to Mac Nab's criteria, 9 patients (50%) reported excellent and the remaining 9 patients (50%) reported good outcomes. The mean preoperative and postoperative VAS for leg pain were 7.36 ± 0.73 and 1.45 ± 0.60, respectively (p < 0.001). Improvement in outcomes was maintained even at final follow-up. There was no complication.

Conclusion

In this preliminary study we achieved good to excellent clinical results using the SCOT of PETLD for high grade inferiorly migrated lumbar disc herniation.

An Amendment to the Neidre and MacNab Classification System for Lumbosacral Nerve Root Anomaly and Its Implication in Percutaneous Endoscopic Lumbar Discectomy

BACKGROUND

Lumbar disc herniation complicated with nerve root anomaly presents great challenges to diagnosis and treatment. Improper selection of surgical procedures may cause inferior outcomes and neurologic injury.

CASE DESCRIPTION

A 66-year old man presented with low back pain and radicular symptoms involving bilateral L5 and S1 nerve roots. Instead of percutaneous endoscopic lumbar discectomy, aggressive decompression was carried out because of a deviation between the examination and imaging findings. Surgical detection disclosed a confluent nerve root comprising 2 adjacent contributions that arose from the thecal sac exiting from the left L5/S1 foramen, in the absence of the root otherwise exiting through the caudal foramen. We found that the overwhelming left radicular symptoms were attributable to compression on this swelling anomalous root by a narrowed L5/S1 root cannula. Aggressive decompression and distraction of the intervertebral space successfully released the nerve root. Twenty months postoperatively, the patient experienced evident relief of the radicular symptoms and improvement of muscle strength with no complication.

CONCLUSIONS

Lumbosacral nerve root anomaly should be remembered and ruled out before selecting surgical methods. Inappropriate procedures can not alleviate the symptoms associated with the anomalous roots and may expose such patients to the risk of neural injury. In clinical practice, surgeons should select percutaneous endoscopic lumbar discectomy with caution, and stop the procedure instantly when unexplainable radicular irritation is evoked.

Percutaneous endoscopic lumbar discectomy for high-grade down-migrated disc using a trans-facet process and pedicle-complex approach: a technical case series

PURPOSE

The use of conventional percutaneous endoscopic lumbar discectomy (PELD) for high-grade down-migrated lumbar disc herniation medial to the pedicle via the transforaminal route can result in less favorable outcomes. We report a new PELD technique for the treatment of high-grade down-migrated lumbar disc herniation via a facet process and pedicle-complex approach.

METHODS

Three patients with high-grade down-migrated L3-4 and L4-5 disc herniation presented to our hospital. Each underwent PELD via a facet process and pedicle complex approach to remove the herniated fragment and achieve complete decompression of the nerve root.

RESULTS

Patients' symptoms were relieved. Postoperative magnetic resonance imaging showed root decompression. Follow-up 12-month computed tomography revealed no pedicle or facet fracture and healing of the pedicle complex and facet process bone tunnel.

CONCLUSION

PELD via a facet process and pedicle-complex approach may be an option for high-grade, down-migrated lumbar disc herniation with completely sequestrated nucleus pulposus.

Percutaneous endoscopic interlaminar discectomy of L5-S1 disc herniation: a comparison between intermittent endoscopy technique and full endoscopy technique

Background

Percutaneous endoscopic laminar discectomy is a typical minimally invasive discectomy operation that is classified into the percutaneous endoscopic transforaminal discectomy and the percutaneous endoscopic interlaminar discectomy. Based on whether the surgeon chooses to deal with the ligamentum flavum under endoscope guidance, percutaneous endoscopic discectomy by the interlaminar approach can be performed with a full endoscope technique with the intermittent endoscope technique. To our knowledge, there is no study comparing these two techniques in regard to their surgical effects and advantages. Therefore, we conducted this study to compare the cost, safety, and efficacy between the intermittent endoscopy technique and full endoscopy technique of endoscopic interlaminar lumbar discectomy at the L5–S1 level.

Methods

From September 2014 to March 2015, a total of 126 patients with radiculopathy due to L5–S1 disc herniation who were treated by a full endoscopy technique (65 patients) or intermittent endoscopy technique (61 patients) were included. Relevant data, such as duration time of the operation, hospitalization expenses, postoperative bed rest time, length of hospitalization, and complication rates, were recorded. Clinical outcomes were assessed by the visual analog scale score, modified MacNab criteria, and Oswestry disability index.

Results

In the full endoscope (FE) group, the mean duration time of surgery was 75.0 ± 11.9 min. The postoperative bed rest time was 6.5 ± 1.1 h, length of hospitalization was 3.8 ± 1.1 days, and complication rate was 7.69%. In the intermittent endoscopy (IE) group, the mean duration time of surgery was 43.0 ± 16.4 min. The postoperative bed rest time was 5.0 ± 1.1 h, length of hospitalization was 3.6 ± 1.2 days, and complication rate was 6.60%. The average hospitalization expenses of the FE group and IE group, respectively, were 32,069 ± 1086 RMB and 22,665 ± 899 RMB. There were significant differences in the surgical duration and hospitalization expenses (P < 0.01), but no differences between the two groups in postoperative bed rest time, length of hospitalization, or complication rates (P > 0.05). The postoperative Oswestry disability index and VAS were clearly improved in both groups compared with those of preoperation (P < 0.01). These two procedures have the same clinical outcomes (P > 0.05).

Conclusions

Both the full endoscopy technique and intermittent endoscopy technique achieved good outcomes, whereas the intermittent endoscopy technique is a more effective option for a shorter duration surgery and lower hospitalization expenses.

Guide wire breakage during posterolateral endoscopic lumbar discectomy procedure: A case report

OBJECTIVE

To present a unique case of guide wire breakage as a rare complication during posterolateral endoscopic lumbar discectomy.

BACKGROUND

Posterolateral endoscopic lumbar discectomy (PELD) has become a routinely performed minimally invasive spinal procedure. However, several complications of PELD have attracted our concerns, including the intraoperative injury to neural and vascular structures and failure of the surgery. We have countered a rare intraoperative complication of guidewire breakage during a PELD procedure, as far as we know, this has not been reported previously, and we wish to draw attention to this hazard.

METHODS

The medical records, operative reports, and radiographical imaging studies of a single patient were retrospectively reviewed.

RESULTS

A 28-year-old man presented with right posterior sciatica for 3 months was admitted to the hospital. Unsatisfactory improvement was observed under supervised conservative treatment. Preoperative magnetic resonance imaging (MRI) showed a disc herniation at the L4-L5 level. After preoperative evaluation, a PELD procedure was performed with local anesthesia. After advancement of guide wire and discography, the guiding rod was found not in the vicinity of the extruding disc fragment. Therefore, the operator tried to redirect the guiding rod. However, after several attempts, the guide wire was broken in the disc fragment under imaging. With the patient's permit, the operator inserted the working cannula to the broken end of guide wire and retrieved it using straightened grasping forceps. Then foraminotomy and fragmentectomy were accomplished under endoscope. The patient made uneventful recovery and was free of symptoms for the following 6 months.

CONCLUSIONS

In conclusion, the guide wire breakage during PELD procedures is a rare but a serious complication. An appropriate manner and operation is very important to prevent this complication. Once it does occur, the remnant of the guide wire can possibly be retrieved under endoscope with great experience. However, as for the beginners, a transfer to open operation is suggested to prevent new complications.

Percutaneous endoscopic transpedicle approach for herniated nucleus pulposus in the lumbar hidden zone

INTRODUCTION

Although endoscopic procedures for lumbar disc diseases have improved greatly, treating migrated disc herniation is still a challenging task. Because of anatomic limitations, a rigid endoscope cannot effectively reach the herniated nucleus pulposus (HNP) in the hidden zone. The purpose of this study was to describe the transpedicle approach for HNP in the hidden zone using the percutaneous endoscopic lumbar discectomy system and to demonstrate the clinical results. Materials and Surgical Technique: Under fluoroscopy, the percutaneous endoscopic lumbar discectomy cannula is placed on the superior articular process, and a trephine with a diameter of 7.3 mm is used to make a bone hole. Through the bone hole, an HNP in the hidden zone can be detected with a rongeur for percutaneous endoscopic lumbar discectomy, the HNP can be removed, and then the decompressed nerve root is verified. We have treated two cases of hidden-zone HNP using the transpedicle approach. In all cases, the HNP was successfully removed, as confirmed by postoperative MRI. Clinical outcomes were acceptable.

DISCUSSION

The percutaneous endoscopic transpedicle approach is an effective technique for managing HNP in the lumbar hidden zone.

Health-related quality of life after transforaminal percutaneous endoscopic discectomy: An analysis according to the level of operation

BACKGROUND

Many patients suffer from radiculopathy and low back pain due to lumbar disc hernia. Transforaminal percutaneous endoscopic discectomy (TPED) is a minimally invasive method that accesses the disc pathology through the intervertebral foramen. Health-related quality of life (HRQoL) has been previously assessed for this method. However, a possible effect of the level of operation on the postoperative progress of HRQoL remains undefined.

PURPOSE

The purpose of this study was to evaluate the impact of the level of operation on HRQoL, following TPED.

PATIENTS AND METHODS

A total of 76 patients diagnosed with lumbar disc hernia were enrolled in the study. According to the level of operation, they were divided into three groups: Group A (21 patients) for L3-L4, Group B (40 patients) for L4-L5, and Group C (15 patients) for L5-S1 intervertebral level. All patients underwent TPED. Their HRQoL was evaluated by the short-form-36 (SF-36) health survey questionnaire before the operation and at 6 weeks, 3, 6, and 12 months postsurgery. The progress of SF-36 was analyzed in relation to the operated level.

RESULTS

All aspects of SF-36 showed statistical significant improvement, at every given time interval (P ≤ 0.05) in the total of patients and in each group separately. Group A had a significantly higher increase in physical functioning (PF) score at 3 and 12 months postsurgery (P = 0.046 and P = 0.056, respectively). On the other hand, Group B had a significant lower increase in mental health (MH) score at 6 months (P = 0.009) postoperatively.

CONCLUSION

Our study concludes that the level of operation in patients who undergo TPED for lumbar disc herniation affects the HRQoL 1 year after surgery, with Group A having a significantly greater improvement of PF in comparison with Groups B and C.

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.

Postoperative seizure following transforaminal percutaneous endoscopic lumbar discectomy

Endoscopic surgery for lumbar disc herniation has been available for more than 30 years. Transforaminal percutaneous endoscopic lumbar discectomy is a well-known, safe, and effective method used for the treatment of the lumbar disc herniation. The published complications of the transforaminal percutaneous endoscopic lumbar discectomy consist of infections, thrombophlebitis, dysesthesia, dural tear, vascular injury, and death. Seizure after transforaminal percutaneous endoscopic lumbar discectomy is an extremely rare complication. A 20-year-old patient applied at our department who had undergone transforaminal percutaneous endoscopic lumbar. During the procedure, while performing the discography, non-ionic contrast media was administered into the thecal sac inadvertently. Two hours after surgery, the patient developed generalized tonic-clonic seizure of 5-min duration. Diagnosis of iohexol-induced seizure was made and the patient was treated supportively without anti-epileptics. Here we present the first case of seizure after transforaminal percutaneous endoscopic lumbar discectomy, which was caused by inadvertent administration of the contrast media into the thecal sac.

Percutaneous Endoscopic Lumbar Discectomy for L5-S1 Disc Herniation Via an Interlaminar Approach Versus a Transforaminal Approach: A Prospective Randomized Controlled Study With 2-Year Follow Up

STUDY DESIGN

A prospective, randomized controlled study of patients with L5-S1 lumbar disc herniations, operated with endoscopic discectomy through an interlaminar or transforaminal approach.

OBJECTIVE

To compare the results of percutaneous endoscopic lumbar discectomy in L5-S1 disc herniation through an interlaminar or transforaminal approach.

SUMMARY OF BACKGROUND DATA

The transforaminal and interlaminar techniques are both acceptable approaches for L5-S1 disc herniation. This is the first study to compare these two approaches in terms of their surgical effects and advantages.

METHODS

From January 2010 to June 2010, 60 patients with L5-S1 disc herniation were randomly recruited into two groups; one group underwent percutaneous endoscopic interlaminar discectomy (PEID) and the other group underwent percutaneous endoscopic transforaminal discectomy (PETD). There were 30 patients in each group. The operation time, intraoperative radiation time, postoperative bed rest time, hospitalization time, and complications were compared between the groups. The surgical effectiveness was assessed according to the Oswestry Disability Index (ODI), Visual Analog Scale (VAS), and modified MacNab criteria.

RESULTS

All the patients completed follow up with a mean of 27.6 months (range, 24-37 months). In the PEID group, the mean operation time was 65.0 ± 14.9 minutes, and the intraoperative radiation time was 0.60 ± 0.24 seconds. For the PETD group, the mean operation time was 86.0 ± 15.4 minutes, and the intraoperative radiation time was 6.50 ± 1.52 seconds. There were significant differences in operation time and radiation time between the two groups (P < 0.01) but not in the postoperative bed rest time, hospitalization time, or complication rate (P > 0.05). The postoperative ODI and VAS were obviously improved in both groups when compared with preoperation (P < 0.01). According to the MacNab criteria, the satisfactory rates were 93.3% and 90.0% in the two groups, without a significant difference (P > 0.05).

CONCLUSION

PEID can escape the blockade of crista iliaca, and advantages include a faster puncture orientation, a shorter operation time, and less intraoperative radiation exposure. PETD requires higher punctuation skill and more intraoperative radiation exposure.

LEVEL OF EVIDENCE

4.

Outcome Measures of an Intracanal, Endoscopic Transforaminal Decompression Technique: Initial Findings from the MIS Prospective Registry

BACKGROUND

Minimally invasive transforaminal endoscopic procedures can achieve spinal decompression through either direct or indirect techniques. Subtle variations in trajectory of the surgical corridor can dictate access to the pathologic tissue. Two general strategies exist: the intradiscal "inside-out" technique and the extradiscal, intracanal (IC) technique. The IC technique utilizes a more lateral transforaminal approach than the intradiscal technique, which allows for a more direct decompression of the spinal canal.

OBJECTIVE

This study is an assessment of IC patient outcome data obtained through analysis of a previously validated MIS Prospective Registry.

METHODS

Post-hoc analysis was performed on the MIS Prospective Registry database containing 1032 patients. A subgroup of patients treated with the endoscopic IC technique was identified. Patient outcome measures after treatment of symptomatic disk herniation and neuroforaminal stenosis were evaluated.

RESULTS

A total of 86 IC patients were analyzed. Overall, there was significant improvement in employment and walking tolerance as soon as 6 weeks post-op as well as significant one year VAS and ODI score improvement. Subanalysis of IC patients with two distinct primary diagnoses was performed. Group IC-1 (disc herniation) showed improvement in ODI and VAS back and leg outcomes at 1 year post-op. Group IC-2 (foraminal stenosis) showed VAS back and leg score improvement at one year post-op but did not demonstrate significant improvement in overall ODI outcome at any time point. The one year re-operation rate was 2% (1/40) for group IC-1 and 28% (5/18) for group IC-2.

CONCLUSIONS

The initial results of the MIS Registry IC subgroup show a significant clinical improvement when the technique is employed to treat patients with lumbar disc herniation. The treatment of foraminal stenosis can lead to improved short-term clinical outcome but is associated with a high re-operation rate at 1 year post-op.

Lumbar Endoscopic Microdiscectomy: Where Are We Now? An Updated Literature Review Focused on Clinical Outcome, Complications, and Rate of Recurrence

Endoscopic disc surgery (EDS) for lumbar spine disc herniation is a well-known but developing field, which is increasingly spreading in the last few years. Rate of recurrence/residual, complications, and outcomes, in comparison with standard microdiscectomy (MD), is still debated and need further data. We performed an extensive review based on the last 6 years of surgical series, systematic reviews, and meta-analyses reported in international, English-written literature. Articles regarding patients treated through endoscopic transforaminal or interlaminar approaches for microdiscectomy (MD) were included in the present review. Papers focused on endoscopic surgery for other spinal diseases were not included. From July 2009 to July 2015, we identified 51 surgical series, 5 systematic reviews, and one meta-analysis reported. In lumbar EDS, rate of complications, length of hospital staying, return to daily activities, and overall patients' satisfaction seem comparable to standard MD. Rate of recurrence/residual seems higher in EDS, although data are nonhomogeneous among different series. Surgical indication and experience of the performing surgeon are crucial factors affecting the outcome. There is growing but still weak evidence that lumbar EDS is a valid and safe alternative to standard open microdiscectomy. Statistically reliable data obtained from randomized controlled trials (better if multicentric) are desirable to further confirm these results.

Endoscopic interlaminar approach for intracanal L5-S1 disc herniation: Classification of disc prolapse in relation to learning curve and surgical outcome

INTRODUCTION

The full endoscopic interlaminar approach (FEILA) is a minimally invasive procedure to treat intracanal lumbar disc herniation not approachable by endoscopic transforaminal access. Disc prolapses have been classified into three categories according to their position and passing nerve root displacement: (i) type A, in which the nerve root is displaced medially; (ii) type B, in which the nerve root is displaced laterally; and (iii) type C, in which the nerve root is ventrally displaced. We focused on the FEILA technique because it was likely to involve few complications and that provided the advantages of the endoscopic approach.

METHODS

We prospectively evaluated 100 consecutive cases of L5-S1 disc herniations operated on with FEILA, including 85 type A cases, 13 type B, and 2 type C. Patients were evaluated at discharge, 3 months, 6 months and 2 years.

RESULTS

The operating time varied from 15 to 40 min. The use of drills and burrs was necessary to treat type B disc herniations; thus, it was preferable that these cases were operated on later in the learning curve. After surgery, 90% of neurological deficits improved. The Oswestry Disability Index and visual analog scale leg at last follow-up were 15 and 9, respectively. There were no major complications. There were five cases of recurrence; four of which were treated with same technique and with good results.

CONCLUSION

FEILA is a safe procedure for the removal of intracanal L5-S1 disc herniations. The late follow-up confirms the stability of the results. We suggest treating type A prolapse at the beginning of the learning curve and type B herniations after sufficient experience in the use of the burrs has been achieved.

Morphometric analysis of the working zone for posterolateral endoscopic lumbar discectomy based on magnetic resonance neurography

STUDY DESIGN

A magnetic resonance neurography (MRN)-based morphometric analysis of the working zone for posterolateral endoscopic lumbar discectomy (PELD) procedures on 32 health volunteers.

OBJECTIVE

The purpose is to utilize MRN as a noninvasive evaluation of the Kambin's working zone, and further to analyze operative safety of the PELD procedures.

SUMMARY OF BACKGROUND DATA

Intraoperative nerve root injuries of PELD procedures occur relative to the Kambin's triangular working zone, which has been described previously based on formalin-fixed cadaver studies. However, the investigation in living individuals is not known. Thus, it is necessary to evaluate the dimensions of the working zone on both coronal and sagittal plane by radiologic assessments.

MATERIALS AND METHODS

MRN images of 32 health volunteers (average age 26.8 y; 18 men, 14 women) were analyzed from L1-L2 to L5-S1. On the coronal plane, we measured the distance from the superior endplate to the nerve root exiting from the dura (distance a), the distance from lateral aspect of the dura to the medial aspect of the nerve root along the superior endplate (distance b), and the angle between the nerve root and plane of the corresponding disk (angle α). On the transversal plane, the vertical distance from the upper facet surface to the exiting nerve root at the lower/upper disk margin level (distance c/d) was also measured.

RESULTS

On the coronal plane, distance a was 16.69±5.07 mm (range, 6.60-26.10 mm), distance b was 13.64±2.52 mm (range, 9.30-21.20 mm), angle α was 55.45±7.14 degrees (range, 40.00-73.00 degrees). Distance c on the transversal plane was 5.01±2.66 mm (range, 1.30-13.10 mm) and distance d was 1.99±1.26 mm (range, 0.70-7.80 mm). All these measurements increased as the spine level went down.

CONCLUSIONS

The study indicated that MRN was a feasible noninvasive tool to evaluate the anatomic dimensions in the Kambin's working zone. Before PELD, radiologic measurements of this working zone were recommended to perform a safer procedure.

Clinical outcomes and efficacy of transforaminal lumbar endoscopic discectomy

Background:

Transforaminal lumbar endoscopic discectomy (TLED) is a minimally invasive procedure for removing lumbar disc herniations. This technique was initially reserved for herniations in the foraminal or extraforaminal region. This study concentrated on our experience regarding the outcomes and efficacy of TLED.

Materials and Methods:

A total of 105 patients were included in the study. The patients were retrospectively evaluated for demographic features, lesion levels, numbers of affected levels, visual analog scores (VASs), Oswestry disability questionnaire scale scores and MacNab pain relief scores.

Results:

A total of 48 female and 57 male patients aged between 25 and 64 years (mean: 41.8 years) underwent TLED procedures. The majority (83%) of the cases were operated on at the levels of L4-5 and L5-S1. Five patients had herniations at two levels. There were significant decreases between the preoperative VAS scores collected postoperatively at 6 months (2.3) and those collected after 1-year (2.5). Two patients were referred for microdiscectomy after TLED due to unsatisfactory pain relief on the 1^st postoperative day. The overall success rate with respect to pain relief was 90.4% (95/105). Seven patients with previous histories of open discectomy at the same level reported fair pain relief after TLED.

Conclusions:

Transforaminal lumbar endoscopic discectomy is a safe and effective alternative to microdiscectomy that is associated with minor tissue trauma. Herniations that involved single levels and foraminal/extraforaminal localizations were associated with better responses to TLED.

Learning curve of full-endoscopic technique through interlaminar approach for L5/S1 disk herniations

Although minimally invasive full-endoscopic (FE) spine surgery through the interlaminar approach has proved safe and effective for surgical treatment of lumbar disk herniation, the learning curve of the procedure has not been sufficiently established. The purpose of this study is to determine the learning curve for the FE surgery through interlaminar approach for treating the L5/S1 disk herniation. Thirty-six patients with lumbar disk herniation (L5/S1 segment) who underwent FE lumbar discectomy through the interlaminar approach between March 2011 and March 2012 were equally divided into Group A, B, and C by the study time of the surgeons. Clinical evaluation data included perioperative parameters (operative duration, intraoperative blood loss, and the amount of intraoperative bone and ligament excision), clinical curative effect index [visual analog scale (VAS) score for leg and back pain], complications, and the rate of conversion to open surgery. The operation duration, intraoperative bleeding, and the amount of bone and ligament excision were gradually and significantly reduced in the Groups A, B, and C (P < 0.01) and reflected in steep curves of proficiency suggesting that the rate of learning was fast. The VAS scores of leg and back pain were significantly improved (P < 0.01) and no symptomatic recurrence was noticed during the follow-up period (1-1.5 years). The outcomes the three groups were not significantly different. The clinical outcomes of the minimally invasive surgery for the treatment of L5/S1 segment disk herniation through the interlaminar approach were excellent suggesting of a satisfactory curative effect. The steep learning curves of perioperative parameters plotted against the number of surgeries conducted suggest that proficiency can be reached reasonably fast.

Minimally invasive percutaneous endoscopic 2 levels adjacent lumbar discectomy through 1 portal skin incision: Preliminary study

Background:

Acute lumbar disc herniation can occur in every lumbar intervertebral disc space and in multiple levels simultaneously. In the cases of 2 levels adjacent lumbar disc herniations of severe unilateral radiculopathic leg pain caused by compression of the nerve roots, respectively, multiple incision or long incision is generally needed for simultaneous removal of disc fragment in 2 levels.

Objectives:

We proposed the minimally invasive one portal skin incision endoscopic discectomy is effective and safe method to treat 2 levels adjacent lumbar disc herniation.

Materials and Methods:

We have experimented total 8 cases of 2 levels adjacent lumbar disc herniation having unilateral radiculopathic pain respectively. All cases are 2 levels adjacent lumbar disc herniation. We have tried a percutaneous endoscopic transforaminal approach through minimal one portal skin incision and remove the two herniated disc materials in the adjacent levels.

Results:

The L2-L3 level was involved in 2 patients, L3-L4 level in 6 patients, while the L4-L5 level was involved in 7 patients, L5-S1 level in 1 patient. The mean follow-up was 18.5 months. The mean visual analogue score (VAS) of the patients prior to surgery was 7.75, and the mean postoperative VAS was 2.375. According to Macnab's criteria, 3 patients had excellent results, 4 patients had good results, 1 patient had fair results, and no patient had a poor result; satisfactory results were obtained in 87.5% of the cases.

Conclusion:

The percutaneous endoscopic transforaminal approach through 1 skin portal incision could be effective surgical method in unilateral adjacent 2 levels lumbar disc herniation.

Economic impact of minimally invasive lumbar surgery

Cost effectiveness has been demonstrated for traditional lumbar discectomy, lumbar laminectomy as well as for instrumented and noninstrumented arthrodesis. While emerging evidence suggests that minimally invasive spine surgery reduces morbidity, duration of hospitalization, and accelerates return to activites of daily living, data regarding cost effectiveness of these novel techniques is limited. The current study analyzes all available data on minimally invasive techniques for lumbar discectomy, decompression, short-segment fusion and deformity surgery. In general, minimally invasive spine procedures appear to hold promise in quicker patient recovery times and earlier return to work. Thus, minimally invasive lumbar spine surgery appears to have the potential to be a cost-effective intervention. Moreover, novel less invasive procedures are less destabilizing and may therefore be utilized in certain indications that traditionally required arthrodesis procedures. However, there is a lack of studies analyzing the economic impact of minimally invasive spine surgery. Future studies are necessary to confirm the durability and further define indications for minimally invasive lumbar spine procedures.

"Outside-in" technique, clinical results, and indications with transforaminal lumbar endoscopic surgery: a retrospective study on 220 patients on applied radiographic classification of foraminal spinal stenosis

OBJECTIVE

To analyze and describe appropriate surgical indications for endoscopically performed transforaminal decompression with the outside-in technique with foraminoplasty in patients with lateral stenosis with and without herniated disc.

BACKGROUND AND SIGNIFICANCE

Endoscopic microdiscectomy is growing in popularity for the removal of lumbar disc herniations. Recent advances in surgical techniques allow for percutaneous endoscopically assisted bony decompression as well.

MATERIALS AND METHODS

A retrospective study of 220 consecutive patients undergoing percutaneous endoscopic transforaminal foraminoplasty and microdiscectomy at 228 levels was conducted with intent of identifying appropriate surgical indications in patients with monoradiculopathy. The mean follow up was 46 months ranging from 26 to 54 months. Preoperatively, foraminal and lateral recess stenosis was graded on preoperative MRI and CT scans by dividing the lumbar neuroforamen into three zones: a) entry zone, b) middle zone, and c) exit zone. In addition, the presence of disc herniation causing neural element compression in the lateral recess and neuroforamen was noted. Disc herniations, if present, were recorded as either extruded and contained disc herniations. Surgical outcomes were classified according to the Macnab criteria. In addition, reductions in VAS scores were assessed.

RESULTS

According to the Macnab criteria, excellent and good results were obtained in 85% (186/220) of patients with monoradiculopathy. The mean VAS score decreased from 7.5 ± 1.5 preoperatively to 2.8 ± 1.9 at the final follow-up (P < 0.01). Concomitant extruded disc herniations and contained disc bulges were recorded in 24 and 82 patients, respectively. There were no approach-related complications. Clinical failures occurred in patients with bony stenosis in the lateral recess and entry zone of the neuroforamen. Less favorable outcomes were observed in patients with concomitant contained disc herniations when compared to extruded disc herniations (P < 0.03) as well in patients older than 50 years of age (P < 0.021).

CONCLUSIONS

Percutaneous, endoscopic decompression using outside-in technique works well in patients with monoradiculopathy due to lateral stenosis in the mid and exit zone of the neuroforamen. Decompression in the entry zone maybe inadequate using the transforaminal outside-in approach. Future studies with greater statistical power should determine as to whether pain relief was achieved via microdiscectomy or foraminoplasty.

"Outside-in" technique, clinical results, and indications with transforaminal lumbar endoscopic surgery: a retrospective study on 220 patients on applied radiographic classification of foraminal spinal stenosis

Objective

To analyze and describe appropriate surgical indications for endoscopically performed transforaminal decompression with the outside-in technique with foraminoplasty in patients with lateral stenosis with and without herniated disc.

Background and Significance

Endoscopic microdiscectomy is growing in popularity for the removal of lumbar disc herniations. Recent advances in surgical techniques allow for percutaneous endoscopically assisted bony decompression as well.

Materials and Methods

A retrospective study of 220 consecutive patients undergoing percutaneous endoscopic transforaminal foraminoplasty and microdiscectomy at 228 levels was conducted with intent of identifying appropriate surgical indications in patients with monoradiculopathy. The mean follow up was 46 months ranging from 26 to 54 months. Preoperatively, foraminal and lateral recess stenosis was graded on preoperative MRI and CT scans by dividing the lumbar neuroforamen into three zones: a) entry zone, b) middle zone, and c) exit zone. In addition, the presence of disc herniation causing neural element compression in the lateral recess and neuroforamen was noted. Disc herniations, if present, were recorded as either extruded and contained disc herniations. Surgical outcomes were classified according to the Macnab criteria. In addition, reductions in VAS scores were assessed.

Results

According to the Macnab criteria, excellent and good results were obtained in 85% (186/220) of patients with monoradiculopathy. The mean VAS score decreased from 7.5 ± 1.5 preoperatively to 2.8 ± 1.9 at the final follow-up (P < 0.01). Concomitant extruded disc herniations and contained disc bulges were recorded in 24 and 82 patients, respectively. There were no approach-related complications. Clinical failures occurred in patients with bony stenosis in the lateral recess and entry zone of the neuroforamen. Less favorable outcomes were observed in patients with concomitant contained disc herniations when compared to extruded disc herniations (P < 0.03) as well in patients older than 50 years of age (P < 0.021).

Conclusions

Percutaneous, endoscopic decompression using outside-in technique works well in patients with monoradiculopathy due to lateral stenosis in the mid and exit zone of the neuroforamen. Decompression in the entry zone maybe inadequate using the transforaminal outside-in approach. Future studies with greater statistical power should determine as to whether pain relief was achieved via microdiscectomy or foraminoplasty.

Transforaminal endoscopic lumbar decompression & foraminoplasty: a 10 year prospective survivability outcome study of the treatment of foraminal stenosis and failed back surgery

Background

Conventional diagnosis between axial and foraminal stenosis is suboptimal and long-term outcomes limited to posterior decompression. Aware state Transforaminal Endoscopic Lumbar Decompression and Foraminoplasty (TELDF) offers a direct aware state means of localizing and treating neuro-claudicant back pain, referred pain and weakness associated with stenosis failing to respond to conventional rehabilitation, pain management or surgery. This prospective survivability study examines the outcomes 10 years after TELDF in patients with foraminal stenosis arising from degeneration or failed back surgery.

Methods

For 10 years prospective data were collected on 114 consecutive patients with multilevel spondylosis and neuro-claudicant back pain, referred pain and weakness with or without failed back surgery whose symptoms had failed to respond to conventional rehabilitation and pain management and who underwent TELDF. The level responsible for the predominant presenting symptoms of foraminal stenosis, determined on clinical grounds, MRI and or CT scans, was confirmed by transforaminal probing and discography. Patients underwent TELDF at the spinal segment at which the predominant presenting symptoms were reproduced. Those that required treatment at an additional segment were excluded. Outcomes were assessed by postal questionnaire with failures being examined by the independent authors using the Visual Analogue Pain Scale (VAPS), the Oswestry Disability Index (ODI) and the Prolo Activity Score.

Results

Cohort integrity was 69%. 79 patients were available for evaluation after removal of the deceased (12), untraceable (17) and decliners (6) from the cohort.

VAP scores improved from a pre-operative mean of 7.3 to 2.4 at year 10. The ODI improved from a mean of 58.5 at baseline to 17.5 at year 10. 72% of reviewed patients fulfilled the definition of an “Excellent” or “Good Clinical Impact” at review using the Spinal Foundation Outcome Score. Based on the Prolo scale, 61 patients (77%) were able to return and continue in full or part-time work or retirement activity post-TELDF. Complications of TELDF were limited to transient nerve irritation, which affected 19% of the cohort for 2 – 4 weeks. TELDF was equally beneficial in those with failed back surgery.

Conclusions

TELDF is a beneficial intervention for the long-term treatment of severely disabled patients with neuro-claudicant symptoms arising from spinal or foraminal stenosis with a dural diameter of more than 3mm, who have failed to respond to conventional rehabilitation or chronic pain management. It results in considerable improvements in symptoms and function sustained 10 years later despite co-morbidity, ageing or the presence of failed back surgery.

Clinical Relevance

The long term outcome of TELDF in severely disabled patients with neuro-claudicant symptoms arising from foraminal stenosis which had failed to respond to conventional rehabilitation, surgery or chronic pain management suggests that foraminal pathology is a major cause of lumbar axial and referred pain and that TELDF should be offered as primary treatment for these conditions even in the elderly and infirm. The application of TELDF at multiple levels may further widen the benefits of this technique.

The "inside out" transforaminal technique to treat lumbar spinal pain in an awake and aware patient under local anesthesia: results and a review of the literature

Surgical management of back and leg pain is evolving and changing due to a better understanding of the patho-anatomy well correlated with its pathophysiology. Pain is better understood with in vivo visualization and probing of the pain generators using an endoscopic access rather than just relying on symptoms diagram and image correlation. This has resulted in a shared decision making involving patient and surgeon, focused on a broader spectrum of surgical as well as non-surgical treatments, and not just masking the pain generator. It has moved away from decisions based on diagnostic images alone, that, while noting the image alterations, cannot explain the pain experienced by each individual as images do not always show variations in nerve supply and patho-anatomy. The ability to isolate and visualize "pain" generators in the foramen and treating persistent pain by visualizing inflammation and compression of nerves, serves as the basis for transforaminal endoscopic (TFE) surgery. This has also resulted in better pre surgical planning with more specific and defined goals in mind. The "Inside out" philosophy of TFE surgery is safe and precise. It provides basic access to the disc and foramen to cover a large spectrum of painful pathologies.

Early postoperative results after removal of cranially migrated lumbar disc prolapse: retrospective comparison of three different surgical strategies

Background. To compare the early postoperative results of three surgical approaches to lumbar disc herniations that migrated cranially. Minimally invasive techniques such as the translaminar and endoscopic transforaminal approaches are utilized in patients with lumbar disc herniations to gain access to cranially located disc material and to avoid the potentially destabilizing resection of ligament and bone tissue, which is associated with an extended interlaminar approach. Methods. This retrospective study compares the postoperative pain and functional capacity levels of 69 patients who underwent an interlaminar (Group A, n = 27), a translaminar (Group B, n = 22), or an endoscopic transforaminal procedure (Group C, n = 20). Results. Median VAS scores for leg pain decreased significantly from before to after surgery in all groups. Surgical revisions were required in thirteen cases (five in Group A, one in Group B, and seven in Group C; P = 0.031). After six weeks, there were significant differences in back pain and functional outcome scores and in the results for the MacNab criteria but not in leg pain scores. Conclusions. The interlaminar and translaminar techniques were the safest and fastest ways of gaining access to cranially migrated disc material and the most effective approaches over a period of six weeks.

Percutaneous endoscopic intra-annular subligamentous herniotomy for large central disc herniation: a technical case report

STUDY DESIGN

Technical case report.

OBJECTIVE

To describe the novel technique of percutaneous endoscopic herniotomy using a unilateral intra-annular subligamentous approach for the treatment of large centrally herniated discs.

SUMMARY OF BACKGROUND DATA

Open discectomy for large central disc herniations may have poor long-term prognosis due to heavy loss of intervertebral disc tissue, segmental instability, and recurrence of pain.

METHODS

Six consecutive patients who presented with back and leg pain, and/or weakness due to a large central disc herniation were treated using percutaneous endoscopic herniotomy with a unilateral intra-annular subligamentous approach.

RESULTS

The patients experienced relief of symptoms and intervertebral disc spaces were well maintained. The annular defects were noted to be in the process of healing and recovery.

CONCLUSION

Percutaneous endoscopic unilateral intra-annular subligamentous herniotomy was an effective and affordable minimally invasive procedure for patients with large central disc herniations, allowing preservation of nonpathological intradiscal tissue through a concentric outer-layer annular approach.

Exiting root injury in transforaminal endoscopic discectomy: preoperative image considerations for safety

PURPOSE

To evaluate the clinical and radiological risk factors for exiting root injuries during transforaminal endoscopic discectomy.

METHODS

We retrospectively examined cohort data from 233 patients who underwent percutaneous endoscopic lumbar discectomy for lumbar disc herniation between January 1st, 2010 and December 31st, 2011. We divided the patients into the two groups: those who presented a postoperative exiting root injury, such as postoperative dysesthesia or motor weakness (Group A, n = 20), and those who did not suffer from a root injury (Group B, n = 213). We examined the clinical and radiological factors relating exiting root injuries. We measured the active working zone with the exiting root to the upper facet distance (Distance A), the exiting root to disc surface distance at the lower facet line (Distance B) and the exiting root to the lower facet distance (Distance C) in magnetic resonance imaging (MRI).

RESULTS

Group A exhibited a shorter Distance C (6.4 ± 1.5 versus 4.4 ± 0.8 mm, p < 0.001) and a longer operation time (67.9 ± 21.8 versus 80.3 ± 23.7 min, p = 0.017) relative to Group B. The complication rate decreased by 23% per each 1-mm increase in Distance C (p = 0.000). In addition, the complication rate increased 1.027-fold per each 1-min increase in the operation time (p = 0.027).

CONCLUSION

We recommend measuring the distance from the exiting root to the facet at the lower disc level according to a preoperative MRI scan. If the distance is narrow, an alternative surgical method, such as microdiscectomy or conventional open discectomy, should be considered.

Clinical results of XMR-assisted percutaneous transforaminal endoscopic lumbar discectomy

Background

Although percutaneous endoscopic lumbar discectomy (PELD) has shown favorable outcomes in the majority of lumbar discectomy cases, there were also some failures. The most common cause of failure is the incomplete removal of disc fragments. The skin entry point for the guide-needle trajectory and the optimal placement of the working sleeve are largely blind, which might lead to the inadequate removal of disc fragments. The objective of this study was to present our early experiences with image-guided PELD using a specially designed fluoroscope with magnetic resonance imaging-equipped operative suite (XMR) for the treatment of lumbar disc herniation.

Methods

This prospective study included 89 patients who had undergone PELD via the transforaminal approach using an XMR protocol. Pre- and postoperative examinations (at 12 weeks) included a detailed clinical history, visual analogue scale (VAS), Oswestry disability index (ODI), and radiological workups. The results were categorized as excellent, good, fair, and poor according to MacNab's criteria. At the final follow-up, the minimum follow-up time for the subjects was 2 years. The need for revision surgeries and postoperative complications were noted on follow-up.

Results

Postoperative mean ODI decreased from 67.4% to 5.61%. Mean VAS score for back and leg pain improved significantly from 4 to 2.3 and from 7.99 to 1.04, respectively. Four (4.49%) patients underwent a second-stage PELD after intraoperative XMR had shown remnant fragments after the first stage. As per MacNab's criteria, 76 patients (85.4%) showed excellent, 8 (8.89%) good, 3 (3.37%) fair, and 2 (2.25) poor results. Four (4.49%) patients had remnant disc fragments on XMR, which were removed during the same procedure. All of these patients had either highly migrated or sequestrated disc fragments preoperatively. Four (4.49%) other patients needed a second, open surgery due to symptomatic postoperative hematoma (n = 2) and recurrent disc herniation (n = 2).

Conclusions

This prospective analysis indicates that XMR-assisted PELD provides a precise skin entry point. It also confirms that decompression occurs intraoperatively, which negates the need for a separate surgery and thus increases the success rate of PELD, particularly in highly migrated or sequestrated discs. However, further extensive experience is required to confirm the advantages and feasibility of PELD in terms of cost effectiveness.

Comparative Study of the Outcomes of Percutaneous Endoscopic Lumbar Discectomy and Microscopic Lumbar Discectomy Using the Tubular Retractor System Based on the VAS, ODI, and SF-36

Objective

Percutaneous endoscopic lumbar discectomy (PELD) and microdiscectomy with the microscope endoscopic tubular retractor system(METRx-MD) are considered popular minimally invasive surgery (MIS) methods for the treatment of lumbar disc herniation. Many authors have also reported good clinical outcomes of these methods, but there are few comparative studies of them. This report compares the clinical outcomes of PELD and METRx-MD for lumbar disc herniation as MIS methods and discusses the efficacy of PELD.

Methods

Seventy-two patients who had undergone single-level unilateral discectomy using two different methods, PELD and METRx-MD, between 2009 and 2011 were given a follow-up examination prospectively. Thirty-seven of these patients underwent discectomy using PELD, and the remaining 35 patients underwent discectomy using METRx-MD. In addition to the general parameters, clinical outcomes were assessed as specific parameters using the Visual Analogue Scale (VAS) score, the Oswestry Disability Index (ODI), the Short-form 36 (SF-36), and the return-to-work time.

Results

Sixty-seven percent (25/37) of the patients in the PELD group and 74%(26/35) in the METRx-MD group were included in follow-up more than 6 months post-operatively. The mean improvements in the VAS scores for the back pain, leg pain, and ODI were 2.6, 4.8, and 30.1% for the PELD group and 2.8, 4.6, and 33.2% for the METRx-MD group, respectively. The SF-36 physical health component subscale score improved from 40.6 pre-operatively to 68.3 at the last follow-up for the PELD group post-operatively, and from 48.5 to 65.1 in the mental component subscale (METRx-MD group: from 34.4 to 66.5 and from 44.87 to 56.7). Complications occurred in 3/37 patients in the PELD group and in 2/35 patients in the METRx-MD group in the peri-operative period. The mean return-to-work times were 37.5 days in the PELD group and 42.5 days in the METRx-MD group.

Conclusion

The outcomes for the PELD group are comparable to those for the METRx-MD group. It can thus be concluded that PELD for lumbar disk herniations may be performed safely and effectively. Also, PELD can be considered one of the treatment modalities of lumbar disk herniation.

Transforaminal endoscopic spinal surgery: the future 'gold standard' for discectomy? - A review

BACKGROUND

Lumbar disc prolapse is common and the primary method of care in most centres is still open discectomy facilitated by microscope or loupe magnification and illumination. Hospitalisation may be less than 24 h, but post-operative pain usually requires an overnight stay. This review describes transforaminal endoscopic spinal surgery (TESS) using HD-video technology, that is generally performed as a day case procedure under sedation or light general anaesthesia, and collates the evidence comparing the technique to microdiscectomy.

METHODS

The method of TESS is described and an electronic literature search performed to identify papers reporting clinical outcomes. International data were translated where necessary and proceedings' abstracts included. In addition, papers held by the authors and colleagues in personal libraries were carefully cross-referenced to the obtained database.

RESULTS

Analysis of the data supports the use of a transforaminal endoscopic approach to the lumbar intervertebral disc and suggests that outcomes following surgery are at least equivalent to those following microdiscectomy. Significant cost-savings in terms of in-patient stay may be generated. In addition, there is also some evidence supporting endoscopic surgery for relief of foraminal stenosis.

CONCLUSION

Based on current evidence there are good arguments supporting a more wide-spread adoption of transforaminal endoscopic surgery for the treatment of lumbar disc prolapse with or without foraminal stenosis.