Transforaminal endoscopic surgery for lumbar stenosis: a systematic review

Analysis of the clinical efficacy of visualization of percutaneous endoscopic lumbar discectomy combined with annulus fibrosus suture in lumbar disc herniation

The objective of this study is to compare the clinical effectiveness of visualization of percutaneous endoscopic lumbar discectomy (VPELD) combined with annulus fibrosus suture technique and simple percutaneous endoscopic lumbar discectomy (PELD) technique in the treatment of lumbar disc herniation. A retrospective analysis was conducted on 106 cases of lumbar disc herniation treated with foraminoscopic technique at our hospital from January 2020 to February 2022. Among them, 33 cases were treated with VPELD combined with annulus fibrosus suture in group A, and 73 cases were treated with PELD in group B. The preoperative and postoperative visual analogue scale (VAS), functional index (Oswestry Disability Index, ODI), healing of the annulus fibrosus, intervertebral space height, and postoperative recurrence were recorded and compared between the two groups. All patients underwent preoperative and postoperative MRI examinations, and the average follow-up period was 12 ± 2 months. Both groups showed significant improvements in postoperative VAS and ODI scores compared to the preoperative scores (P < 0.05), with no statistically significant difference between the groups during the same period (P > 0.05). There was no significant decrease in intervertebral space between the two groups after surgery (P > 0.05). Group A showed significantly lower postoperative recurrence rate and better annulus fibrosus healing compared to group B (P < 0.05). The VPELD combined with annulus fibrosus suture technique is a safe, feasible, and effective procedure for the treatment of lumbar disc herniation. When the indications are strictly adhered to, this technique can effectively reduce the postoperative recurrence rate and reoperation rate. It offers satisfactory clinical efficacy and can be considered as an alternative treatment option for eligible patients.

Outcome of Transforaminal Endoscopic Discectomy in Rural India in a Single-Level Lumbar Disc Prolapse Under Local Anesthesia

Aim  The aim of this study was to undertake a clinical study to evaluate the outcomes of transforaminal endoscopic discectomy under local anesthesia and to study the complication rate. Study Design  It is a prospective study. Methods  We prospectively analyzed outcomes of 60 patients with a single-level lumbar disc prolapse in rural India from December 2018 to April 2020 who underwent endoscopic discectomy under local anesthesia. Follow-up was done using the visual analogue score (VAS) and Oswestry Disability Index (ODI) scoring systems with a minimum follow-up up to 1 year postoperatively. Results  In our study of 60 patients, there was 38 cases of L4-L5 disc pathology, 13 L5-S1 discs, and 9 L3-L4 discs. Our study showed a significant clinical reduction in mean VAS score that was 7.07/10 preoperatively and reduced to 3.88/10 at the third month and 3.64/10 at 1 year of follow-up ( p -value < 0.05) showing clinical significance. The ODI scoring done preoperatively was an average mean of 57.37% pointing to how crippled the patients were with lumbar disc prolapse and showed a significant reduction to 29.32% postoperatively at 1 year ( p -value < 0.05) showing clinical significance. This reduction in ODI directly corelates to how almost all patients returned to normal life coping to all activities and were completely pain free at 1 year of follow-up. Conclusion  Endoscopic spine surgery in lumbar disc prolapse is highly effective and can deliver a good functional outcome if done with correct preoperative planning and approach.

Extraforaminal Full-Endoscopic Approach for the Treatment of Lateral Compressive Diseases of the Lumbar Spine

Background: The authors conducted a 2-year retrospective follow-up to investigate the efficiency of an extraforaminal full-endoscopic approach with foraminoplasty used to treat lateral compressive diseases of the lumbar spine in 247 patients. Methods: The visual analogue scale (VAS), Oswestry disability index (ODI), and MacNab scale were used to analyze the results collected during the preoperative and postoperative periods. Results: The most common diagnosis was disk herniation with lateral recess stenosis, and the most common surgical level among patients was between L4 and L5 on the left side. Pain decreased over time, as determined during sessions held to evaluate pain in the lumbar, gluteal, led, and foot regions. The ODI demonstrated significant enhancement over the evaluation period and the MacNab scale classified the surgery as good or excellent. The most common complication was dysesthesia. Conclusions: An extraforaminal full-endoscopic approach with foraminoplasty can be recommended in cases of lateral herniation or stenosis for patients with symptoms of radiculopathy, and for those who have not responded to conventional rehabilitation treatment or chronic pain management. Few complications arose as a result of this approach, and most of them were treated clinically.

Full-endoscopic technique for posterior fossa decompression in Chiari malformation type I: An anatomical feasibility study in human cadavers

Although endoscope-assisted techniques have been described, a full-endoscopic approach is yet to be performed for posterior fossa decompression (PFD) in Chiari malformation type I (CM-I). This study aims to describe the full-endoscopic PFD technique and evaluate its feasibility. Five fresh-frozen anonymized adult human cadavers were operated on using an endoscope with an oval shaft cross-section with a diameter of 9.3 mm, a working length of 177 mm, and a viewing angle of 20°. It also had an eccentric working channel with a diameter of 5.6 mm, a light guide, a sheath for continuous irrigation, and a rod lens system. The instruments were introduced from the working channel. Posterior craniocervical structures were dissected, and PFD was achieved. The planned steps were performed in all five cadavers. The endoscope was introduced to the posterior craniocervical region, dissecting the structures to easily expose the suboccipital bone and C1 posterior arch. Important structures, such as the C1 posterior tubercle, rectus capitis posterior minor muscles, and posterior atlantooccipital membrane, were used as landmarks. PFD was feasible even with the dural opening. Using the full-endoscopic approach, posterior craniocervical structures can be reached, and PFD can be performed successfully. The instruments used are well-defined for spinal usage; thus, this full-endoscopic technique can be widely used in the surgical treatment of patients with CM-I.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Transforaminal Endoscopic Decompression of Facet Cysts by Interventional Pain Physicians

Lumbar synovial cysts (LSC) can impinge neural structures, causing radicular back pain. Conservative treatment options; however, are often ineffective, and traditional surgical techniques can cause joint instability. We describe two cases in which interventional pain physicians used transforaminal endoscopic spine surgery to treat LSC. The patients reported complete resolution of their lower back and radicular pain and the procedures preserved their motor function and sensation in their bilateral lower extremities. This technique is a viable option for remediation of LSC and can be performed by well-trained pain physicians.

Clinical and radiological outcomes of endoscopic foraminoplasty and decompression assisted with preoperative planning software for lumbar foraminal stenosis

PURPOSE

To assess the clinical and radiological outcomes of using endoscopic foraminoplasty and decompression assisted with a preoperative planning software in the treatment of lumbar foraminal stenosis.

METHODS

This retrospective study included 43 patients with lumbar foraminal stenosis (Jan 2018 and June 2019). These patients were divided into two groups. Patients in the conventional group (group A) underwent endoscopic lumbar foraminoplasty and decompression. Patients in the experimental group (group B) underwent the same surgery assisted with a preoperative software. The total operation time, puncture-channel establishment time, and the number of intraoperative fluoroscopic images taken were recorded. The Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) were administered preoperatively and postoperatively (at 1-month, 3-month, and 12-month follow-up). The modified MacNab criteria were used to assess the global outcome at 12-month follow-up.

RESULTS

Patients in group B had shorter operation time, puncture-channel establishment time, and less number of intraoperative fluoroscopic images taken, as compared with group A. The VAS and ODI scores were significantly lower than pre-operation for both groups at all follow-ups. No significant difference was observed between these two groups. Based on the modified MacNab criteria, the excellent-to-good rate was 86.4% in group A and 90.5% in group B, respectively. After the operation, no patients had residual osteophytes in group B, while two patients still had residual osteophytes and foraminal stenosis in group A.

CONCLUSION

For endoscopic surgery treating lumbar foraminal stenosis, using preoperative planning software could reduce the puncture-channel establishment time, operation time, and the number of intraoperative fluoroscopic images taken without affecting the clinical outcomes.

Percutaneous Endoscopic Lumbar Discectomy via Transforaminal Approach Combined with Interlaminar Approach for L4/5 and L5/S1 Two-Level Disc Herniation

Objective

The purpose of the present study was to discuss a new surgical strategy that combines percutaneous endoscopic transforaminal discectomy (PETD) with percutaneous endoscopic interlaminar discectomy (PEID) for L4/5 and L5/S1 two‐level disc herniation.

Methods

This was a retrospective study. A total of 19 patients with L4/5 and L5/S1 two‐level lumbar disc herniation (LDH) who underwent percutaneous endoscopic lumbar discectomy (PELD) in our hospital from January 2015 to June 2016 were retrospectively examined. The average age of these 19 patients was 42.21 ± 14.88 years old, including 12 men and 7 women. One experienced surgeon who had carried out more than 3000 lumbar surgeries performed PELD for these patients. During the PELD surgery, the transforaminal approach was adopted for L4/5 level disc herniation and the interlaminar approach was adopted for L5/S1 level disc herniation. The demographic data, operation time (min), fluoroscopy times, hospital stay (days), and complications were recorded and analyzed. The visual analogue scale (VAS), Oswestry disability index (ODI) scores, and the modified MacNab criteria were used to evaluate the surgical outcomes. MRI was conducted to evaluate the radiographic improvement.

Results

All patients underwent PELD via the transforaminal approach combined with the interlaminar approach successfully and achieved satisfactory efficacy. The follow‐up points were 3, 12, and 18 months. The average hospital stay (days) and the average follow up (months) were 3.32 ± 0.98 and 18.63 ± 3.84, respectively. The operation time and fluoroscopy times were 85.79 ± 12.90 min and 39.05 ± 4.59 times, respectively. The fluoroscopy times (frequency) for L4/5 and L5/S1 were 26.95 ± 6.41 and 12.11 ± 3.49 (t = 7.00, P < 0.05). Furthermore, there was no significant difference for fluoroscopy times between male and female patients (t = 0.89, P = 0.99). The preoperative back pain (VAS‐Back) and the last follow‐up VAS‐Back were 5.58 ± 2.01 and 2.37 ± 1.01, respectively (t = 7.14, P < 0.05). The preoperative leg pain (VAS‐Leg) and the last follow‐up VAS‐Leg were 7.00 ± 1.56 and 1.63 ± 1.01, respectively (t = 20.97, P < 0.05). There were significant differences between preoperative VAS‐Back and the last follow‐up VAS‐Back in men (t = 4.61, P < 0.05) and women (t = 6.57, P < 0.05). In addition, there was significant differences between preoperative VAS‐Leg and the last follow‐up VAS‐Leg in men (t = 13.48, P < 0.05) and women (t = 26.87, P < 0.05). There were significant differences between preoperative ODI scores (44.84 ± 10.82%) and the last follow‐up ODI scores (11.12 ± 5.80%) (t = 10.92, P < 0.05). Preoperative ODI scores and the last follow‐up ODI scores were significantly different for men (t = 8.80, P < 0.05) and women (t = 6.63, P < 0.05). All patients received significant pain relief and functional improvement after the surgery. Except for two cases of postoperative dysesthesia and one dural tear, no severe complications occurred. The dysesthesia symptoms of these two patients disappeared within 1 week with the application of dexamethasone and neurotrophic drugs and the dural tear case also recovered well as the dural laceration was small. No poor results were reported and 89.47% of patients achieved excellent or good recovery.

Conclusion

Percutaneous endoscopic lumbar discectomy via the transforaminal approach combined with the interlaminar approach under epidural anesthesia can treat L4/5 and L5/S1 two‐level disc herniation safely and effectively.

Does Robot Navigation and Intraoperative Computed Tomography Guidance Help with Percutaneous Endoscopic Lumbar Discectomy? A Match-Paired Study

OBJECTIVE

To evaluate the efficacy and safety of robot-assisted percutaneous endoscopic lumbar discectomy (rPELD) using a specially designed orthopaedic robot with an intraoperative computed tomography-equipped suite for treatment of symptomatic lumbar disc herniation and compare rPELD with fluoroscopy-assisted percutaneous endoscopic lumbar discectomy (fPELD).

METHODS

We retrospectively reviewed and compared demographic data, radiologic workups, and patient-reported outcomes of 39 patients treated with rPELD and 78 patients treated with fPELD at our institution between January 2019 and December 2019.

RESULTS

Our data showed that a single-shot puncture in the rPELD group was significantly more precise compared with 4.12 ± 1.71 trials in the fPELD group (P < 0.001). There was an overall reduction of fluoroscopy (21.33 ± 3.89 times vs. 33.06 ± 2.92 times, P < 0.001), puncture-channel time (13.34 ± 3.03 minutes vs. 15.03 ± 4.5 minutes, P = 0.038), and total operative time (57.46 ± 7.49 minutes vs. 69.40 ± 12.59 minutes, P < 0.001) using the rPELD technique versus the fPELD technique. However, there were no significant differences in patient-reported outcomes, length of hospital stay, and complication rate between the 2 groups (P > 0.05).

CONCLUSIONS

Taken together, our data indicate that rPELD provides a precise skin entry point and optimal trajectory for puncture, which increases the success rate of PELD, negating the need for revision surgery. However, further studies are required to confirm the superiority and application of the rPELD technique.

Percutaneous Endoscopic Transforaminal Lumbar Discectomy via Eccentric Trepan foraminoplasty Technology for Unilateral Stenosed Serve Root Canals

Objective

To evaluate the clinical outcomes of percutaneous lumbar foraminoplasty for unilateral stenosed nerve root canals.

Methods

The article is a retrospective analysis. From May 2016 to April 2017, 32 patients with lumbar spinal stenosis syndrome (unilateral stenosed nerve root canals) were treated with percutaneous endoscopic transforaminal lumbar discectomy (PETLD). The study included 15 men and 17 women, with an average age of 53.8 ± 15.4 years, ranging from 24 to 78 years. The indexes used for preoperative and postoperative 1 day, 3 months, and final follow up were the visual analogue scale (VAS) for lumbar and leg, the Oswestry disability index (ODI), and the modified Macnab criteria. All patients were followed up for an average 6 months after the operation.

Results

The average operative time was 75.82 ± 10.58 min, the average blood loss was 15.83 ± 3.75 mL, and the average hospital stay after surgery was 6.2 ± 4.6 days. The VAS score (leg) decreased from 6.94 ± 0.50 preoperatively to 1.16 ± 0.45 at the final follow up (P < 0.05) and ODI were obviously improved, from preoperative evaluation of 80.19 ± 5.55 to 9.44 ± 1.16 at the final follow up (P < 0.05). However, the postoperative VAS score (lumbar) did not show an improvement, reducing from 1.78 ± 0.49 preoperatively to 1.62 ± 0.55 at the final follow‐up (P > 0.05). According to the modified Macnab criteria, the outcome showed that the excellent and good rate was 90.6%. There were three patients with hip soreness, and nerve root symptoms were relieved.

Conclusion

Percutaneous endoscopic transforaminal lumbar discectomy has a satisfactory clinical effect in the treatment of lumbar spinal stenosis syndrome, especially for unilateral stenosed nerve root canals, and in decompressing the lateral recess and relieving the nerve root symptoms.

Comparison of Effects of PELD and Fenestration in the Treatment of Geriatric Lumbar Lateral Recess Stenosis

Purpose

Although degenerative lumbar spinal stenosis (LSS) is increasingly being diagnosed in older people, there is much uncertainty about the appropriate operative treatment options. The objective of this study was to compare the outcome of percutaneous endoscopic lumbar decompression (PELD) versus fenestration for lumbar lateral recess stenosis (LRS) in geriatric patients over 75 years old.

Materials and methods

This prospective controlled study was performed on 46 consecutive over aged patients with lateral recess stenosis who underwent either PELD or fenestration. Clinical data were recorded before, 1 week, 3 months and 1.5 years after surgery using visual analog scale (VAS), Japanese Orthopaedic Association Score (JOA), The Short-Form-36 (SF-36), and the modified Macnab evaluation criteria.

Results

The patients’ mean age was 82.7 years (aged 75–93 years) in PELD group and 79.1 years (aged 75–88 years) in fenestration group. No statistical difference was found between PELD group and fenestration group with regards to VAS-back pain, VAS-leg pain, JOA and at 3 months and 1.5-year follow-up. However, the PELD group had a lower mean VAS for back pain at 1 week postoperatively (P<0.05). The quality of life in PELD group achieved the same remarkable improvement as fenestration group (P>0.05). Operative time (min) was similar between two groups (p>0.05), while the PELD techniques brought advantages in blood loss (mL) (48.3 vs 128.2, p<0.05), early ambulation (h) (5.5 vs 25.2, p<0.05), and anesthesia-related complications.

Conclusion

Both PELD and fenestration showed favorable clinical outcomes for the treatment of lumbar lateral recess stenosis. In addition, PELD had advantages such as reduced traumatization and less anesthesia-related complications. In terms of quality of life and complications after operation, PELD under local anesthesia could be an efficient supplement to conventional decompression surgery in geriatric patients with lumbar lateral recess stenosis.

Learning curve and clinical outcomes of percutaneous endoscopic transforaminal decompression for lumbar spinal stenosis

PURPOSE

To define and analyze the learning curve of percutaneous endoscopic transforaminal decompression (PETD) for lumbar spinal stenosis (LSS).

METHODS

From July 2015 to September 2016, 78 patients underwent PETD; one of whom was converted to open surgery, two were lost, and 75 were included in this study. Clinical results were assessed by using the Oswestry Disability Index (ODI) and visual analog scale (VAS). The learning curve was assessed by a logarithmic curve-fitting regression analysis. Of these 75 patients, 35 were defined as the "early" group, and 40 were defined as the "late" group for comparison.

RESULTS

The mean follow-up was 25.37 ± 4.71 months. The median operative time gradually decreased from 95 (interquartile range, IQR, 85-110) minutes for the early group to 70 (IQR, 60-80) minutes for the late group (P < .000), and an asymptote was reached after approximately 35 cases. After surgery, the VAS for leg pain (LP) and ODI decreased significantly and remained constant during the follow-up. However, the VAS of low back pain (LBP) increased mildly. The total complication rate was 6.6%. ODI, VAS of LP and of LBP, and complication rate did not significantly differ between two groups. Early ambulation and short hospital stay after surgery were achieved.

CONCLUSION

The learning curve of PETD for LSS was assessed and good clinical results were achieved. The surgeon's experience with this technique correlated with reduced operation time. Proper patient selection, familiarity with pathological anatomy, and manipulation under endoscopic view may shorten the learning curve and decrease complications.

Learning Curve for Percutaneous Endoscopic Lumbar Diskectomy in Bi-needle Technique Using Cumulative Summation Test for Learning Curve

BACKGROUND

The purpose of this study was to determine the number of cases needed to achieve the level of competence for percutaneous endoscopic lumbar diskectomy (PELD) via the bi-needle technique using the cumulative summation test for learning curve (LC-CUSUM).

METHODS

A retrospective design was used. We included 60 patients who underwent a single-level PELD via the bi-needle technique performed by a single surgeon. The surgeon had 5 years of experience in open surgery including the transforaminal endoscopic spine system and Yeung endoscopic spine system but no experience in the bi-needle technique. Surgery success was defined as an operative time <60 minutes, and the acceptable procedure was completed within 3 times of C-arm fluoroscopies. The LC-CUSUM was used to analyze the data.

RESULTS

The average operative time for PELD via the bi-needle technique was 58.3 ± 12.4 minutes. The mean operative time was 65.7 ± 12.1 minutes in the early learning period (30 cases) and 51.0 ± 7.5 minutes in the late learning period (30 cases) (P < 0.05). On the basis of the evaluation indexes of the operative time and radioactive exposure, the LC-CUSUM signaled proficiency for the bi-needle technique at the 50th-54th operation. Seven cases of complications were observed during the whole learning process, with 6 in the early period and 1 in the late period (P < 0.05).

CONCLUSIONS

The novel bi-needle technique is safe and effective for PELD with appropriate patients, and the learning curve is acceptable. A substantial learning period (50-54 cases) is needed before a spine surgeon can master the bi-needle technique.

Endoscopic transforaminal lumbar interbody fusion: a comprehensive review

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Comparison of Transforaminal Percutaneous Endoscopic Lumbar Discectomy with and without Foraminoplasty for Lumbar Disc Herniation: A 2-Year Follow-Up

Background

Both transforaminal percutaneous endoscopic lumbar discectomy with foraminoplasty (TF PELF) and transforaminal percutaneous endoscopic lumbar discectomy without foraminoplasty (TF PELD) were developed for lumbar disc herniation (LDH) patients. However, the safety and effectiveness between the TF PELF and TF PELD have not been investigated.

Methods

Of the included 140 LDH patients, 62 patients received TF PELF (PELF group) and 78 patients received TF PELD (PELD group). The operation time, the duration of staying at the hospital, and complication incidences were recorded. All patients were followed up for 2 years, where low back and leg visual analogue scale (VAS) pain ratings and Oswestry Disability Index (ODI) were compared between the 2 groups before and after surgery. Modified Macnab criterion was estimated for all patients at postoperative 2 years.

Results

There were no significant difference of the operation time, number of days staying at the hospital, and the incidence of complications between the 2 groups (P > 0.05). Two cases in the PELF group and 1 case in the PELD group received a second surgery due to unrelieved symptoms postoperatively. Low back and leg VAS and ODI scores decreased in both groups after operation (P < 0.01), respectively, but were not significant between the 2 groups over time (P > 0.05). Six patients in the PELF group and 3 patients in the PELD group did not continue the follow-up; thus, only 131 patients completed Macnab evaluation. The satisfactory rate was reported as 80.4% in the PELF group and 90.7% in the PELD group (P > 0.05).

Conclusions

This study suggested that the safety and effectiveness of TF PELF are comparable to TF PELD for LDH patients.

Efficacy and Safety of Full-endoscopic Decompression via Interlaminar Approach for Central or Lateral Recess Spinal Stenosis of the Lumbar Spine: A Meta-analysis

STUDY DESIGN

A meta-analysis of five retrospective cohort studies.

OBJECTIVE

The aim of the study was to delineate the efficacy and safety of full-endoscopic decompression via the interlaminar approach for central or lateral recess spinal stenosis of the lumbar spine using a meta-analysis.

SUMMARY OF BACKGROUND DATA

The paradigm of spinal endoscopy is shifting from treatment of soft disc herniation to that of lumbar spinal stenosis. Technical advancements have enabled full-endoscopic decompression in spinal stenosis surgery. There is few strong evidence supporting this surgical technique, and clinicians usually rely on their own opinions and experiences.

METHODS

A systematic search of electronic databases, including PubMed, EMBASE, Cochrane Library, Web of science, and KoreaMed, up to August 2017 was performed to identify studies concerning full-endoscopic decompression via the interlaminar approach for lumbar spinal stenosis. Changes in clinical outcomes [Oswestry Disability Index (ODI) and Visual Analog Scales (VAS) for back and leg pain] were compared with the minimal clinically important difference (MCID) for each item. We then calculated the mean differences and 95% confidence intervals (95% CIs) using random-effects models.

RESULTS

We included data from five studies involving 156 patients at 6- and 12-month follow-ups. The majority of enrolled papers included patients with neurogenic claudication due to central stenosis refractory to conservative management and excluded patients with significant instability or previous surgery. The overall mean difference of patients with ODI and VAS scores for leg and back pain exceeded the criteria for MCID. ODI scores improved by 41.71 (95% CI, 39.80-43.62) after the surgery, which was twice the MCID. The VAS leg and back pain scores improved by 5.95 (95% CI, 5.70-6.21) and 4.22 (95% CI, 3.88-4.56), respectively, indicating statistically significant improvement over the MCID.

CONCLUSION

Successful clinical outcomes can be achieved with full-endoscopic decompression via the interlaminar approach for lumbar central spinal stenosis in patients for the defined indications.

LEVEL OF EVIDENCE

2.

Transforaminal Percutaneous Endoscopic Lumbar Decompression by Using Rigid Bendable Burr for Lumbar Lateral Recess Stenosis: Technique and Clinical Outcome

Background

Open laminectomy has been regarded as the standard surgical procedure for lumbar lateral recess stenosis during the last decades. Although percutaneous endoscopic lumbar decompression has led to successful results comparable with open decompression, its application in LSS with is still challenging and technically demanding. Here, we report the surgical procedure and preliminary clinical outcomes of transforaminal percutaneous endoscopic lumbar decompression (PELD) by using flexible burr for lumbar lateral recess stenosis.

Method

A retrospective study was performed for the patients with lumbar lateral recess stenosis receiving PELD by using flexible burr. The indications of surgery were moderate to severe stenosis, persistent neurological symptoms, and failure of conservative treatment. The patients with mechanical back pain, more than grade I spondylolisthesis, or radiographic signs of instability were not included. Before the operation, the transforaminal epidural lidocaine injections were carried out to make the diagnosis more precise and accurate. Radiologic findings were investigated, and visual analog scale (VAS) for back and leg pain, Oswestry Disability Index, and modified Macnab criteria were analyzed at the different time of preoperation, postoperation, 3 months, 6 months, and 12 months.

Results

The follow-up period was 12 months. The mean VAS scores for back and leg pain immediately improved from 7.9 ± 1.2 to 2.8± 1.3, 2.4 ± 1.0, and 2.3 ± 1.0, respectively. The mean visual analog scale scores (VAS) for back pain and leg pain were significantly improved after PELD. The preoperative ODI dropped from 69.1 ± 7.3 to 25.9 ± 8.7, 25.0± 6.9, and 24.7 ± 6.4, respectively. The final outcome was excellent in 39.6%, good in 47.9%, fair in 8.3%, and poor in 4.17%. 87.5% of excellent-to-good ratio was achieved on the basis of Macnab criteria at postoperative 12 months. The complications were limited to transient postoperative dysesthesia (one case), temporary pain aggravation (six cases), and neck pain during the operation (one case).

Conclusion

This observation suggests that the clinical outcomes of PELD for lateral recess stenosis were excellent or showed good results. This minimally invasive technique would be helpful in choosing a surgical method for lateral recess stenosis.

Isocentric Navigation for the Training of Percutaneous Endoscopic Transforaminal Discectomy: A Feasibility Study

Background

Percutaneous endoscopic transforaminal discectomy (PETD) is usually chosen for lumbar disc herniation due to its obvious advantages such as small incision and absence of nerve or muscular traction. However, learning PETD is a great challenge for inexperienced surgeons.

Objective

The study aimed to investigate whether isocentric navigation would be beneficial in PETD training.

Methods

A total of 117 inexperienced surgeons were trained with PETD at L2/3, L3/4, L4/5, and L5/S1 on the cadavers without (Group A n=58) or with (Group B n=59) isocentric navigation. Puncture times, fluoroscopy times, exposure time, and radiation dose were recorded and analyzed. Questionnaires were conducted before and after the training program.

Result

Isocentric navigation could improve young surgeons' satisfaction with the training program and decrease the puncture times, fluoroscopy times, exposure time, and radiation dose significantly (P<0.001).

Conclusion

Isocentric navigation contributes to the training of PETD and may improve its standardization, homogenization, and generalization.

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.

Early Outcomes of Endoscopic Contralateral Foraminal and Lateral Recess Decompression via an Interlaminar Approach in Patients with Unilateral Radiculopathy from Unilateral Foraminal Stenosis

OBJECTIVE

Percutaneous endoscopic contralateral interlaminar lumbar foraminotomy (PECILF) for lumbar degenerative spinal stenosis is an established procedure. Better preservation of contralateral facet joint compared with that of the approach side has been shown with uniportal bilateral decompression. The aim of this retrospective case series was to analyze the early clinical and radiologic outcomes of stand-alone contralateral foraminotomy and lateral recess decompression using PECILF.

METHODS

Twenty-six consecutive patients with unilateral lower limb radiculopathy underwent contralateral foraminotomy and lateral recess decompression using PECILF. Their clinical outcomes were evaluated with visual analog scale leg pain score, Oswestry Disability Index, and the MacNab criteria. Completeness of decompression was documented with a postoperative magnetic resonance imaging.

RESULTS

Mean age for the study group was 62.9 ± 9.2 years and the male/female ratio was 4:9. A total of 30 levels were decompressed, with 18 patients (60%) undergoing decompression at L4-L5, 9 at L5-S1 (30%), 2 at L3-L4 (6.7%), and 1 at L2-L3 (3.3%). Mean estimated blood loss was 27 ± 15 mL per level. Mean operative duration was 48 ± 12 minutes/level. Visual analog scale leg score improved from 7.7 ± 1 to 1.8 ± 0.8 (P < 0.0001). Oswestry Disability Index improved from 64.4 ± 5.8 to 21 ± 4.5 (P < 0.0001). Mean follow-up of the study was 13.7 ± 2.7 months. According to the MacNab criteria, 10 patients (38.5%) had good results, 14 patients (53.8%) had excellent results, and 2 patients (7.7%) had fair results. One patient required revision surgery.

CONCLUSIONS

Facet-preserving contralateral foraminotomy and lateral recess decompression with PECILF is effective for treatment of lateral recess and foraminal stenosis. Thorough decompression with acceptable early clinical outcomes and minimal perioperative morbidity can be obtained with the contralateral endoscopic approach.

Electrophysiological and Anatomical Correlates of Spinal Cord Optical Coherence Tomography

Despite the continuous improvement in medical imaging technology, visualizing the spinal cord poses severe problems due to structural or incidental causes, such as small access space and motion artifacts. In addition, positional guidance on the spinal cord is not commonly available during surgery, with the exception of neuronavigation techniques based on static pre-surgical data and of radiation-based methods, such as fluoroscopy. A fast, bedside, intraoperative real-time imaging, particularly necessary during the positioning of endoscopic probes or tools, is an unsolved issue. The objective of our work, performed on experimental rats, is to demonstrate potential intraoperative spinal cord imaging and probe guidance by optical coherence tomography (OCT). Concurrently, we aimed to demonstrate that the electromagnetic OCT irradiation exerted no particular effect at the neuronal and synaptic levels. OCT is a user-friendly, low-cost and endoscopy-compatible photonics-based imaging technique. In particular, by using a Fourier-domain OCT imager, operating at 850 nm wavelength and scanning transversally with respect to the spinal cord, we have been able to: 1) accurately image tissue structures in an animal model (muscle, spine bone, cerebro-spinal fluid, dura mater and spinal cord), and 2) identify the position of a recording microelectrode approaching and inserting into the cord tissue 3) check that the infrared radiation has no actual effect on the electrophysiological activity of spinal neurons. The technique, potentially extendable to full three-dimensional image reconstruction, shows prospective further application not only in endoscopic intraoperative analyses and for probe insertion guidance, but also in emergency and adverse situations (e.g. after trauma) for damage recognition, diagnosis and fast image-guided intervention.

Endoscopic inter laminar management of lumbar disease

Discectomy for lumbar disc provides faster relief in acute attack than does conservative management. Long-term results of open, microscopy-, and endoscopy-assisted discectomy are same. Early results of endoscopy-assisted surgery are better as compared to that of open surgery in terms of better visualization, smaller incision, reduced hospital stay, better education, lower cost, less pain, early return to work, and rehabilitation. Although microscopic discectomy also has comparable advantages, endoscopic-assisted technique better addresses opposite side pathology. Inter laminar technique (ILT) and trans foraminal technique (TFT) are two main endoscopic approaches for lumbar pathologies. Endoscopy-assisted ILT can be performed in recurrent, migrated, and calcified discs. All lumbar levels including L5-S1 level, intracanalicular, foraminal disc, lumbar canal and lateral recess stenosis, multiple levels, and bilateral lesions can be managed by ILT. Migrated, calcified discs, L5-S1 pathology, lumbar canal, and lateral recess stenosis can be better approached by ILT than by TFT. Most spinal surgeons are familiar with anatomy of ILT. It can be safely performed in foramen stenosis and in uncooperative and anxious patients. There is less risk of exiting nerve root damage, especially in short pedicles and in presence of facet osteophytes as compared to TFT. On the other hand, ILT is more invasive than TFT with more chances of perforations of the dura matter, pseudomeningocele formation, and cerebrospinal fluid fistula in early learning curve. Obtaining microsurgical experience, attending workshops, and suitable patient selection can help shorten the learning curve. Once adequate skill is acquired, this procedure is safe and effective. The surgeon must be prepared to convert to an open procedure, especially in early learning curve. Spinal endoscopy is likely to achieve more roles in future. Endoscopy-assisted ILT is a safer alternative to the microscopic technique.

Percutaneous lumbar foraminoplasty and percutaneous endoscopic lumbar decompression for lateral recess stenosis through transforaminal approach: Technique notes and 2 years follow-up

OBJECTIVE

To evaluate the outcome and safety of percutaneous lumbar foraminoplasty (PLF) and percutaneous endoscopic lumbar decompression (PELD) with specially designed instrument for lumbar lateral recess stenosis with/without herniated discs (HDs).

METHOD

From August of 2011 to August of 2013, 96 patients met the inclusion criteria were treated with PLF-PELD and 85 cases were followed up to 2 years postoperatively. MRI or CT checkup performed in the next morning after operation. Outcomes of symptoms were evaluated by follow-up interviews at 3 months, 6 months, 1 year and 2 years after surgery. Low back pain and leg pain were measured by Visual Analog Scale (VAS) score (1-100). Functional outcomes were assessed by using Oswestry Disability Index (ODI) and modified MacNab criteria.

RESULT

Two years follow-up data were obtained from 85 cases, including 14 cases on unilateral L3-4, 1 case on bilateral L3-4, 49 cases on unilateral L4-5, 3 cases on bilateral L4-5, 12 cases on unilateral L5S1, 1 case on bilateral L5S1, 3 cases on unilateral L3-5 and 2 cases on unilateral L4-S1. So totally 95 lumbar lateral recesses were decompressed. Patients ranged in age from 46-78 years (mean age, 56.7 years), including 36 males and 49 females. 56 cases combined with HDs. Low back pain and leg pain were significantly relieved after surgery in all patients. 3 patients were complicated with dysesthesia in distribution of exiting nerve that was all operated at L5S1. Postoperative MRI/CT examination showed adequate decompression of lateral recess and removal of combined HDs in all patients. No patient had postoperative infection, dysfunctional nerve root injury or iatrogenic segmental instability. 2 cases experienced recurrence of combined HDs (2.4%), but could not undertake further revision surgery because of infirm condition. All the 85 cases were analyzed with complete follow-up data. VAS scores and ODI values were significantly lower in all time-points after surgery than before surgery. MacNab scores at 2 years after surgery were obtained from all the 85 patients. 29 cases were given "excellent"; 48 were given "good". 6 patients experienced heavier low back pain, thus being classified as "fair". 2 cases with recurrence were given "poor".

CONCLUSIONS

PLF-PELD with specially designed instrument is a less invasive, effective and safe surgery for lumbar lateral recess stenosis with/without combined HDs.

Puncture Reduction in Percutaneous Transforaminal Endoscopic Discectomy with HE's Lumbar LOcation (HELLO) System: A Cadaver Study

BACKGROUND

Percutaneous transforaminal endoscopic discectomy (PTED) usually requires numerous punctures under X-ray fluoroscopy. Repeated puncture will lead to more radiation exposure and reduce the beginners' confidence.

OBJECTIVE

This cadaver study aimed to investigate the efficacy of HE's Lumbar Location (HELLO) system in puncture reduction of PTED.

STUDY DESIGN

Cadaver study.

SETTING

Comparative groups.

METHODS

HELLO system consists of self-made surface locator and puncture locator. One senior surgeon conducted the puncture procedure of PTED on the left side of 20 cadavers at L4/L5 and L5/S1 level with the assistance of HELLO system (Group A). Additionally, the senior surgeon conducted the puncture procedure of PTED on the right side of the cadavers at L4/L5 and L5/S1 level with traditional methods (Group B). On the other hand, an inexperienced surgeon conducted the puncture procedure of PTED on the left side of the cadavers at L4/L5 and L5/S1 level with the assistance of our HELLO system (Group C).

RESULTS

At L4/L5 level, there was significant difference in puncture times between Group A and Group B (P<0.001), but no significant difference was observed between Group A and Group C (P = 0.811). Similarly at L5/S1 level, there was significant difference in puncture times between Group A and Group B (P<0.001), but no significant difference was observed between Group A and Group C (P = 0.981). At L4/L5 level, there was significant difference in fluoroscopy time between Group A and Group B (P<0.001), but no significant difference was observed between Group A and Group C (P = 0.290). Similarly at L5/S1 level, there was significant difference in fluoroscopy time between Group A and Group B (P<0.001), but no significant difference was observed between Group A and Group C (P = 0.523). As for radiation exposure, HELLO system reduced 39%-45% radiation dosage when comparing Group A and Group B, but there was no significant difference in radiation exposure between Group A and Group C whatever at L4/L5 level or L5/S1 level (P>0.05). There was no difference in location time between Group A and Group B or Group A and Group C either at L4/L5 level or L5/S1 level (P>0.05).

LIMITATIONS

Small-sample preclinical study.

CONCLUSION

HELLO system was effective in reducing puncture times, fluoroscopy time and radiation exposure, as well as the difficulty of learning PTED. (2015-RES-127).

Significant Improvement of Puncture Accuracy and Fluoroscopy Reduction in Percutaneous Transforaminal Endoscopic Discectomy With Novel Lumbar Location System: Preliminary Report of Prospective Hello Study

Prospective nonrandomized control study.The study aimed to investigate the implication of the HE's Lumbar LOcation (HELLO) system in improving the puncture accuracy and reducing fluoroscopy in percutaneous transforaminal endoscopic discectomy (PTED).Percutaneous transforaminal endoscopic discectomy is one of the most popular minimally invasive spine surgeries that heavily depend on repeated fluoroscopy. Increased fluoroscopy will induce higher radiation exposure to surgeons and patients. Accurate puncture in PTED can be achieved by accurate preoperative location and definite trajectory.The HELLO system mainly consists of self-made surface locator and puncture-assisted device. The surface locator was used to identify the exact puncture target and the puncture-assisted device was used to optimize the puncture trajectory. Patients who had single L4/5 or L5/S1 lumbar intervertebral disc herniation and underwent PTED were included the study. Patients receiving the HELLO system were assigned in Group A, and those taking conventional method were assigned in Group B. Study primary endpoint was puncture times and fluoroscopic times, and the secondary endpoint was location time and operation time.A total of 62 patients who received PTED were included in this study. The average age was 45.35 ± 8.70 years in Group A and 46.61 ± 7.84 years in Group B (P = 0.552). There were no significant differences in gender, body mass index, conservative time, and surgical segment between the 2 groups (P > 0.05). The puncture times were 1.19 ± 0.48 in Group A and 6.03 ± 1.87 in Group B (P < 0.001). The fluoroscopic times were 14.03 ± 2.54 in Group A and 25.19 ± 4.28 in Group B (P < 0.001). The preoperative location time was 4.67 ± 1.41 minutes in Group A and 6.98 ± 0.94 minutes in Group B (P < 0.001). The operation time was 79.42 ± 10.15 minutes in Group A and 89.65 ± 14.06 minutes in Group B (P = 0.002). The hospital stay was 2.77 ± 0.95 days in Group A and 2.87 ± 1.02 days in Group B (P = 0.702). There were no significant differences in the complication rate between the 2 groups (P = 0.386).The highlight of HELLO system is accurate preoperative location and definite trajectory. This preliminary report indicated that the HELLO system significantly improves the puncture accuracy of PTED and reduces the fluoroscopic times, preoperative location time, as well as operation time. (ChiCTR-ICR-15006730).

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.

Evaluations of computed tomography images and lumbar specimens in mimic operations of transverse rotation laminoplasty for lumbar spinal stenosis

Background:

Laminectomy is a major method to treat lumbar spinal stenosis (LSS), but it has lots of flaws such as scar tissue can form around the dura again or spinal instability. This study aimed to investigate the feasibility of transverse rotation laminoplasty (TRL) in the treatment of LSS.

Methods:

The mimic operations of TRL were performed both in the computerized image processing and on the lumbar specimen. Computed tomography (CT) images were either collected from 80 clinical patients with complaints of lumbago or obtained from 40 sets of lumbar specimens after rebuild of spinal canals. In the CT image processing the heights of the spinous process and laminae at L3–L5 were measured. The total length of the spinous process plus one side laminae after the operation was evaluated and compared with the length of inner margin of pedical before the operation. The areas of the vertebral canal were examined before and after the operation.

Results:

In the CT images, the height of spinous process of L3, L4 and L5 was 24.74 ± 3.45, 22.68 ± 5.96 and 21.54 ± 4.12 mm respectively, and that of laminae was 23.66 ± 2.32, 22.68 ± 5.36 and 20.99 ± 3.67 mm respectively (P > 0.05). Distance of inner border of pedical of L3, L4 and L5 was 23.01 ± 6.59, 24.65 ± 5.54 and 26.03 ± 7.34 mm respectively, and length of spinous process with laminae of those was 29.76 ± 4.91, 29.31 ± 6.43 and 32.53 ± 5.76 mm respectively (P < 0.05). Preoperative area of spinal canals of L3, L4 and L5 was 299.81 ± 10.09, 297.66 ± 9.54 and 308.22 ± 10.04 mm² respectively, and postoperative area was 480.01 ± 9.33, 487.32 ± 8.65 and 501.03 ± 9.12 mm² respectively (P < 0.05). In the human lumbar vertebrae specimen, the data similar to the former.

Conclusions:

The excised canal posterior was covered, and the lumbar canals enlarged by TRL. The TRL provided a new alternative in the treatment of LSS.

Endoscopic foraminal decompression for failed back surgery syndrome under local anesthesia

BACKGROUND

The most common causes of failed back surgery are residual or recurrent herniation, foraminal fibrosis and foraminal stenosis that is ignored, untreated, or undertreated. Residual back ache may also be from facetal causes or denervation and scarring of the paraspinal muscles.(1-6) The original surgeon may advise his patient that nothing more can be done on the basis of his opinion that the nerve was visually decompressed by the original surgery, supported by improved post-op imaging and follow-up studies such as EMG and conduction velocity studies. Post-op imaging or electrophysiological assessment may be inadequate to explain all the reasons for residual or recurrent symptoms. Treatment of Failed back surgery by repeat traditional open revision surgery usually incorporates more extensive decompression causing increased instability and back pain, therefore necessitating fusion. The authors, having limited their practice to endoscopic MIS surgery over the last 15-20 years, report on their experience gained during that period to relieve pain by endoscopically visualizing and treating unrecognized causative patho-anatomy in FBSS.(7.)

METHODS

Thirty consecutive patients with FBSS presenting with back and leg pain that had supporting imaging diagnosis of lateral stenosis and /or residual / recurrent disc herniation, or whose pain complaint was supported by relief from diagnostic and therapeutic injections (Figure 1), were offered percutaneous transforaminal endoscopic discectomy and foraminoplasty over a repeat open procedure. Each patient sought consultation following a transient successful, partially successful or unsuccessful open translaminar surgical treatment for disc herniation or spinal stenosis. Endoscopic foraminoplasty was also performed to either decompress the bony foramen for foraminal stenosis, or foraminoplasty to allow for endoscopic visual examination of the affected traversing and exiting nerve roots in the axilla, also known as the "hidden zone" of Macnab (Figure 2).(8, 9) The average follow up time was, average 40 months, minimum 12 months. Outcome data at each visit included Macnab, VAS and ODI. Fig. 1A diagnostic and therapeutic epidural gram may help identify unrecognized lateral recess stenosis underestimated by MRI. An excellent result from a therapeutic block lends excellent prognosis for a more lasting and "permanent" result from transforaminal endoscopic lateral recess decompression.Fig. 2Kambin's Triangle provides access to the "hidden zone" of Macnab by foraminoplasty. The foramen and lateral recess is decompressed by removing the ventral aspect and tip of the superior articular process to gain access to the axilla between the traversing and exiting nerve. FBSS contains patho-anatomy in the axilla between the traversing and exiting nerve that hides the pain generators of FBSS.

RESULTS

The average pre-operative VAS improved from 7.2 to 4.0, and ODI 48% to 31%. While temporary dysesthesia occurred in 4 patients in the early post-operative period, all were happy, as all received additional relief of their pre-op symptoms. They were also relieved to be able to avoid "open" decompression or fusion surgery.

CONCLUSIONS / LEVEL OF EVIDENCE 3

The transforaminal endoscopic approach is effective for FBSS due to residual/recurrent HNP and lateral stenosis. Failed initial index surgery may involve failure to recognize patho-anatomy in the axilla of the foramen housing the traversing and the exiting nerve, including the DRG, which is located cephalad and near the tip of SAP.(10) The transforaminal endoscopic approach effectively decompresses the foramen and does not further destabilize the spine needing stabilization.(11) It also avoids going through the previous surgical site.

CLINICAL RELEVANCE

Disc narrowing as a consequence of translaminar discectomy and progressive degenerative narrowing and spondylolisthesis (Figure 3) as a natural history of degenerative disc disease can lead to central and lateral stenosis. The MRI may underestimate the degree of stenosis from a bulging or a foraminal disc protrusion and residual lateral recess stenosis. Pain can be diagnosed and confirmed by evocative discography and by clinical response to transforaminal diagnostic and therapeutic steroid injections.(12) Foraminal endoscopic decompression of the lateral recess is a MIS technique that does not "burn bridges" for a more conventional approach and it adds to the surgical armamentarium of FBSS. Fig. 3Cadaver Illustration of Foraminal Stenosis (courtesy of Wolfgang Rauschning). As the disc narrows, the superior articular process impinges on the exiting nerve and DRG, creating lateral recess stenosis, lumbar spondylosis, and facet arthrosis.

Percutaneous endoscopic decompression for lumbar spinal stenosis

Percutaneous endoscopic lumbar discectomy has become a representative minimally invasive spine surgery for lumbar disc herniation. Due to the remarkable evolution in the techniques available, the paradigm of spinal endoscopy is shifting from treatments of soft disc herniation to those of lumbar spinal stenosis. Lumbar spinal stenosis can be classified into three categories according to pathological zone as follows: central stenosis, lateral recess stenosis and foraminal stenosis. Moreover, percutaneous endoscopic decompression (PED) techniques may vary according to the type of lumbar stenosis, including interlaminar PED, transforaminal PED and endoscopic lumbar foraminotomy. However, these techniques are continuously evolving. In the near future, PED for lumbar stenosis may be an efficient alternative to conventional open lumbar decompression surgery.

Comparison of the efficacy and safety between interspinous process distraction device and open decompression surgery in treating lumbar spinal stenosis: a meta analysis

OBJECTIVES

The present study performed a meta-analysis to evaluate the efficacy and safety of interspinous process distraction device (IPD) compared with open decompression surgery (ODS) in treating lumbar spinal stenosis.

METHODS

Literatures were searched in the databases including Cochrane Library, Pubmed, OvidSP, Sciencedirect, Web of Science, and Springerlin. Published reviews were checked to track missed original research papers. The quality and bias of publications with randomized controlled trial were evaluated using the tool for assessing risk of bias in the Cochrane handbook. The quality and bias of publications with cohort trial were evaluated using the Newcastle-Ottawa Scale. The grades of literatures were evaluated with the guidelines of Grading of Recommendations Assessment Development and Evaluation (GRADE).

RESULTS

Totally, 21 publications matched the inclusion criteria, including 20 different clinical trials and 54,138 patients. The results indicated that there was no significant difference in improvement rate, Oswestry disability index questionnaire (ODI) score, and visual analog scale (VAS) score of back pain or leg pain between IPD group and ODS group. The postoperation complication rate, perioperation blood loss, hospitalization time, and operation time were lower/shorter in IPD group than ODS group. However, the reoperation rate in IPD group was higher than ODS group.

CONCLUSION

The results indicated that IPD has better effects and less complication than ODS. However, because of the higher reoperation rate in IPD than ODS, we failed to conclude that IPD could replace ODS as golden standard but may be a viable alternative in treating lumbar spinal stenosis.

Clinical outcomes following sublaminar-trimming laminoplasty for extensive lumbar canal stenosis

PURPOSE

Current surgical approaches for treatment of lumbar canal stenosis are often associated with relatively high rates of reoperation and recurrent stenosis. We have developed a new approach for treatment of this condition: sublaminar-trimming laminoplasty. To describe the surgical approach of sublaminar-trimming laminoplasty and to assess associated outcomes.

METHODS

Patients with extensive lumbar canal stenosis who received sublaminar-trimming laminoplasty from 2006 to 2008 were considered for inclusion in the study. The surgery comprised aspects of laminotomy and laminectomy. The following were assessed before surgery and 3 years after surgery: leg and back pain by visual analog scale (VAS), extent of disability by Oswestry Disability Index (ODI), severity of back pain by Japanese Orthopedic Association Score for Back Pain (JOA), walking tolerance, and leg numbness. Complications were noted.

RESULTS

A total of 49 patients were included in the study (mean age 65.6 ± 10.6 years). VAS leg and back pain, ODI, and JOA scores significantly changed from before surgery to 3 years after surgery (P < 0.001). Mean changes (95 % confidence interval) were -6.2 (-6.7, -5.7), -4.3 (-4.8, -3.8), -21.4 (-23.4, -19.5), and 13.4 (12.1, 14.7) for leg pain, back pain, ODI, and JOA scores, respectively. Patients experienced significant improvements in walking tolerance and leg numbness (P < 0.001). There were no instances of recurrent stenosis or postoperative spinal instability. Complications included intraoperative dural tear (n = 2), postoperative urinary tract infection (n = 2), and inadequate decompression and junctional stenosis during follow-up (both n = 1).

CONCLUSION

Sublaminar-trimming laminoplasty shows promise as an effective treatment for extensive lumbar canal stenosis.

Interspinous spacers for lumbar foraminal stenosis: formal trials are justified

PURPOSE

To determine whether preliminary evidence supports X-STOP implants as an effective treatment for lumbar radiculopathy secondary to foraminal stenosis, and if larger formal trials are warranted.

METHODS

Participants had a clinical diagnosis of lumbar radiculopathy supported by MRI findings of foraminal stenosis and relevant nerve root compression. Self-reported disability and pain were measured pre-operation, early and late post-operation using the widely used Oswestry Disablity Index (ODI) and the bodily pain scale of the Medical Outcomes Study 36-item Short Form Health Survey (SF-36BP). The statistical significance (paired samples t test; Wilcoxon signed ranks test), and clinical significance (Cohen's effect size; Standardised response means) of change scores was determined.

RESULTS

Fifteen people had X-STOP implants. Data pre- early- and late post-operation were available for ten. Self-reported disability and pain improved substantially by the early post operative measurement. Mean change scores (ODI = 29; SF-36BP = -45), significant at the p < 0.05 but not significant at the p < 0.001, were very large and effect sizes exceeded notably criteria for large clinical improvements (>0.80). Improvements were maintained at 2-3 years. Both scales had floor and ceiling effects implying changes may be underestimated. There were no surgical complications.

CONCLUSIONS

In this small study, X-STOP appeared safe and effective. It is less invasive than other established surgical procedures, but does not jeopardise other options in the event of failure. Large scale clinical trials are justified but floor and ceiling effects suggest that the ODI and SF-36 may not be the best choice of outcome measures for those studies.

[Learning curve for lumbar disc surgery]

BACKGROUND AND PURPOSE

Various techniques are available for lumbar disc surgery. But failure and severe adverse events still occur during such procedures. Recent work concluded that the use of microscope was not mandatory for such procedures.

METHODS

The first 70 spinal procedures for lower limb radicular syndrome by a surgeon at the beginning of this activity where studied. Particular interest was paid on adverse events, especially complications and failures.

RESULT

Average duration of surgery (50min) and rate of reoperation (six reoperations needed out of 65 patients, five of them by the same surgeon) where, as expected, a bit higher than published in experienced hands. But no battered-root syndrome, injury to neighboring structures or other severe complication was observed. Noteworthy is that no patient was neurologically worsened by surgery.

CONCLUSIONS

If the use of microscope may not be needed for lumbar disc open surgery in experienced hands, we strongly advice surgeons at the beginning of their practice to use it. At least, to avoid unforgiving mistakes such as picking out the root instead of the 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.