Percutaneous Transforaminal Endoscopic Discectomy for Adjacent Segment Disease After Lumbar Fusion in Elderly Patients Over 65 Years Old

Comparative study of percutaneous endoscopic lumbar decompression and traditional revision surgery in the treatment of symptomatic adjacent segment degeneration

OBJECTIVE

The objective of this study is to evaluate and compare the surgical outcomes and complications of Percutaneous Endoscopic Lumbar Decompression (PELD) and traditional revision surgery in treating symptomatic Adjacent Segment Degeneration (ASD). This comparison aims to delineate the advantages and disadvantages of these methods, assisting spine surgeons in making informed surgical decisions.

METHODS

66 patients with symptomatic ASD who failed conservative treatment for more than 1 month and received repeated lumbar surgery were retrospectively collected in the study from January 2015 to November 2018, with the average age of 65.86 ± 11.04 years old. According to the type of surgery they received, all the patients were divided in 2 groups, including 32 patients replaced the prior rod in Group A and 34 patients received PELD at the adjacent level in Group B. Patients were followed up routinely and received clinical and radiological evaluation at 3, 6, 12 months and yearly postoperatively. Complications and hospital costs were recorded through chart reviews.

RESULTS

The majority of patients experienced positive surgical outcomes. However, three cases encountered complications. Notably, Group B patients demonstrated superior pain relief and improved postoperative functional scores throughout the follow-up period, alongside reduced hospital costs (P < 0.05). Additionally, significant reductions in average operative time, blood loss, and hospital stay were observed in Group B (P < 0.05). Notwithstanding these benefits, three patients in Group B experienced disc re-herniation and underwent subsequent revision surgeries.

CONCLUSIONS

While PELD offers several advantages over traditional revision surgery, such as reduced operative time, blood loss, and hospital stay, it also presents a higher likelihood of requiring subsequent revision surgeries. Future studies involving a larger cohort and extended follow-up periods are essential to fully assess the relative benefits and drawbacks of these surgical approaches for ASD.

Biomechanical Evaluation of 2 Endoscopic Spine Surgery Methods for Treating Lumbar Disc Herniation: A Finite Element Study

OBJECTIVE

This study aimed to evaluate the effects of 2 endoscopic spine surgeries on the biomechanical properties of normal and osteoporotic spines.

METHODS

Based on computed tomography images of a healthy adult volunteer, 6 finite element models were created. After validating the normal intact model, a concentrated force of 400 N and a moment of 7.5 Nm were exerted on the upper surface of L3 to simulate 6 physiological activities of the spine. Five types of indices were used to assess the biomechanical properties of the 6 models, range of motion (ROM), maximum displacement value, intervertebral disc stress, maximum stress value, and articular protrusion stress, and by combining them with finite element stress cloud.

RESULTS

In normal and osteoporotic spines, there was no meaningful change in ROM or disc stress in the 2 surgical models for the 6 motion states. Model N1 (osteoporotic percutaneous transforaminal endoscopic discectomy model) showed a decrease in maximum displacement value of 20.28% in right lateral bending. Model M2 (unilateral biportal endoscopic model) increased maximum displacement values of 16.88% and 17.82% during left and right lateral bending, respectively. The maximum stress value of L4-5 increased by 11.72% for model M2 during left rotation. In addition, using the same surgical approach, ROM, maximum displacement values, disc stress, and maximum stress values were more significant in the osteoporotic model than in the normal model.

CONCLUSION

In both normal and osteoporotic spines, both surgical approaches were less disruptive to the physiologic structure of the spine. Furthermore, using the same endoscopic spine surgery, normal spine biomechanical properties are superior to osteoporotic spines.

Extreme cases in percutaneous transforaminal endoscopic surgery: case series and brief review of the literature

PURPOSE

Percutaneous transforaminal endoscopic decompression (PTED) is a minimally invasive method of surgical treatment of miscellaneous spinal conditions. We describe our experience with PTED in extreme cases of foraminal stenosis (FS) in adult degenerative scoliosis (ADS), recurrent foraminal stenosis (RFS) after previous open decompression surgery and adjacent segment disease (ASD) after previous lumbar fusion.

METHODS

Twenty-one (21) patients with FS encountered in the clinical framework of ADS (n = 6), previous open decompression surgery (n = 8) and ASD (n = 7) were prospectively reviewed. Patients were preoperatively assessed via clinical and radiologic evaluation. All patients underwent PTED in 2018-2019. Postoperative evaluation was conducted with clinical examination and evaluation of Visual Analogue Scale (VAS), Oswestry Disability Index (ODI) and modified MacNab criteria in predetermined chronic intervals in a 1-2 years follow-up.

RESULTS

All patients were successfully managed with PTED. Operated levels were L3-L4 (19.0%), L4-L5 (52.4%) and L5-S1 (28.6%). No major perioperative complications were recorded. VAS and ODI scores were demonstrated to exhibit a clinically and statistically significant (p < 0.05) amelioration in all patients' categories directly postoperatively, which was preserved until the end of follow-up. Overall outcomes according to modified MacNab criteria were excellent in 12 patients (57.1%), good in 6 (28.6%) and fair in 3 (14.3%) patients.

CONCLUSIONS

PTED is safe and effective in extreme cases of FS encountered in patients with ADS, previous posterior open decompression surgery and ASD after previous spinal fusion.

Transforaminal endoscopic lumbar foraminotomy for octogenarian patients

Background

Radiculopathy caused by lumbar foraminal stenosis in older people has become more common in the aging general population. However, patients aged ≥80 years rarely undergo conventional open surgery under general anesthesia because of the high risk of peri-operative morbidity and adverse events. Therefore, less invasive surgical alternatives are needed for older or medically handicapped patients. Transforaminal endoscopic lumbar foraminotomy (TELF) under local anesthesia may be helpful in at-risk patients, although only limited information is available regarding the clinical outcomes of this procedure in octogenarians. Therefore, this study aimed to investigate the safety and efficacy of TELF for treating radiculopathy induced by foraminal stenosis in octogenarian patients.

Methods

Overall, 32 consecutive octogenarian patients with lumbar foraminal stenosis underwent TELF between January 2019 and January 2021. The inclusion criterion was unilateral radiculopathy secondary to lumbar foraminal stenosis. The pain focus was confirmed using imaging studies and selective nerve blocks. Full-scale foraminal decompression was performed using a percutaneous transforaminal endoscopic approach under local anesthesia. Surgical outcomes were assessed using the visual analog pain score, Oswestry Disability Index, and modified MacNab criteria.

Results

The pain scores and functional outcomes improved significantly during the 24-month follow-up period, and the rate of clinical improvement was 93.75% in 30 of the 32 patients. None of the patients experienced systemic complications.

Conclusion

TELF under local anesthesia is an effective and safe treatment for foraminal stenosis in octogenarian or medically compromised patients. The mid-term follow-up did not reveal any significant progression in spinal stability. Therefore, this endoscopic procedure can be an effective alternative to aggressive surgery for managing lumbar foraminal stenosis in octogenarian patients with intractable radiculopathy.

Transforaminal Endoscopic Lumbar Lateral Recess Decompression for Octogenarian Patients

The incidence of radiculopathy due to lumbar spinal stenosis has been on the increase in the aging population. However, patients aged ≥ 80 years hesitate to undergo conventional open surgery under general anesthesia because of the risk of postoperative morbidity and adverse events. Therefore, less invasive surgical alternatives are required for the elderly or medically handicapped patients. Transforaminal endoscopic lumbar lateral recess decompression (TELLRD) may be helpful for those patients. This study aimed to demonstrate the efficacy of TELLRD for treating radiculopathy in octogenarian patients. A total of 21 consecutive octogenarian patients with lumbar foraminal stenosis underwent TELLRD between January 2017 and January 2021. The inclusion criterion was unilateral radiculopathy, which stemmed from lumbar lateral recess stenosis. The pain source was verified using imaging studies and selective nerve blocks. Full-scale lateral canal decompression was performed using a percutaneous transforaminal endoscopic approach under local anesthesia. We found the pain scores and functional status improved significantly during the 24-month follow-up period. The clinical improvement rate was 95.24% (20 of 21 patients) with no systemic complication. In conclusion, endoscopic lateral recess decompression via the transforaminal approach is practical for octogenarian patients.

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

BACKGROUND

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

Lumbar adjacent segment degeneration after spinal fusion surgery: a systematic review and meta-analysis

INTRODUCTION

Adjacent segment degeneration is among the most recognized long-term complications of lumbar surgery for degenerative spine pathologies with a relevant impact in spine surgical and clinical practice. It is reported a incidence of clinical adjacent segment disease between 5-30% of patients undergoing spinal fusion. We aimed to evaluate the main clinical and surgical risk factors for developing adjacent segment disease.

EVIDENCE ACQUISITION

A systematic review and meta-analysis of the pertinent literature was performed, according to PRISMA and PICO guidelines, focusing on clinical and radiological adjacent segment disease. We exclusively included studies reporting demographic and clinical data, and surgical details published from 30 September 2015 to 30 September 2020. The effect of considered risk factors on the presence of adjacent segment disease was explored with a random-effects model.

EVIDENCE SYNTHESIS

A total of 15 scientific publications, corresponding to 6253 patients, met the inclusion criteria for the qualitative and quantitative analysis. 720 of the patients developed a clinical and/or radiological adjacent syndrome disease, and 473 have been surgically managed. Ten articles qualified for the comparative geographical analysis. Advanced age and obesity are relevant risk factors for developing lumbar adjacent segment degeneration. Our data also reported a higher prevalence of adjacent segment degeneration in Western populations than in Eastern populations. The interbody fusion has a protective role toward lumbar adjacent segment degeneration.

CONCLUSIONS

This study highlighted multifactorial issues regarding adjacent segment disease: clinical, anatomical, biomechanical, and radiological features. In view of increasing life expectancy and spinal surgery procedures, extensive multicenter studies will be needed to define the correct management of the adjacent segment disease.

Comprehensive comparison of three techniques for the treatment of adjacent segment degeneration after lumbar fusion

Purpose

Adjacent segment degeneration (ASD) following lumbar fusion is technically challenging for spine surgeons. Posterolateral open fusion surgery with pedicle screw fixation is an effective way to treat symptomatic ASD with favorable clinical outcomes; however, it is associated with an increased morbidity rate. Therefore, minimally invasive spine surgery is advocated. This study was designed to compare clinical outcomes among patients with symptomatic ASD who underwent percutaneous transforaminal endoscopic discectomy (PTED) with the transforaminal approach, posterior lumbar interbody fusion (PLIF) with cortical bone trajectory screw fixation (CBT-PLIF), and PLIF with traditional trajectory screw fixation (TT-PLIF).

Methods

A retrospective study was conductedon 46 patients (26 men and 20 women; average age 60.8 ± 6.78 years) with symptomatic ASD. The patients were treated with three approaches. The operation time, incision length, time to return to work, complications, and the like were compared among three groups. Intervertebral disc (IVD) space height, angular motion, and vertebral slippage were obtained to assess spine biomechanical stability following surgery. The visual analog scale (VAS) score and Oswestry disability index were evaluated at preoperation and 1-week, 3-month, and the latest follow-ups. Clinical global outcomes were also estimated using modified MacNab criteria.

Results

The operation time, incision length, intraoperative blood loss, and time to return to work for the PTED group were significantly decreased compared with those for the other two groups (P &lt; 0.05). The radiological indicators in the CBT-PLIF group and TT-PLIF group had better biomechanical stability compared with those in the PTED groups at the latest follow-up (P &lt; 0.05). The back pain VAS score in the CBT-PLIF group was significantly decreased compared with those in the other two groups at the latest follow-up (P &lt; 0.05). The good-to-excellent rate was 82.35% in the PTED group, 88.89% in the CBT-PLIF group, and 85.00% in the TT-PLIF group. No serious complications were encountered. Two patients experienced dysesthesia in the PTED group; screw malposition was found in one patient in the CBT-PLIF group. One case with a dural matter tear was observed in the TT-PLIF group.

Conclusion

All three approaches can treat patients with symptomatic ASD efficiently and safely. Functional recovery was more accelerated in the PTED group compared with the other approaches in the short term; CBT-PLIF and TT-PLIF can provide superior biomechanical stability to the lumbosacral spine following decompression compared with PTED; however, compared with TT-PLIF, CBT-PLIF can significantly reduce back pain caused by iatrogenic muscle injury and improve functional recovery. Therefore, superior clinical outcomes were achieved in the CBT-PLIF group compared with the PTED and TT-PLIF groups in the long term.

Teleexercise for geriatric patients with failed back surgery syndrome

Introduction

Failed back surgery syndrome (FBSS) is defined as back pain which either persists after attempted surgical intervention or originates after a spine surgery. There is a high risk of perioperative morbidity and a high likelihood of extensive revision surgery in geriatric patients with FBSS or post-laminectomy foraminal stenosis.

Methods

There is a need for less invasive methodologies for the treatment of FBSS, such as patient-tailored exercise training, with attention to the cost and special needs of the geriatric patients with FBSS. This commentary will provide some background regarding teleexercise (utilizing an internet-based platform for the provision of exercise-related care) for FBSS and will propose three exercises which are easy to administer over online-based platforms and can be the subject of future investigation.

Results

Given the documented benefits of regular rehabilitative exercises for patients with FBSS, the high cost of face-to-face services, and the need for infection mitigation in the wake of the COVID-19 Pandemic, teleexercise may be a practical and cost-beneficial method of exercise delivery, especially for geriatric patients with limitations in mobility and access to care. It should be noted that, prescription of these exercises should be done after face-to-face evaluation by the physician and careful evaluation for any “red flag” symptoms.

Conclusion

In this commentary, we will suggest three practical exercise training methodologies and discuss the benefits of teleexercise for geriatric patients with FBSS. Future research should aim to assess the efficacy of these exercises, especially when administered through telehealth platforms.

Safety and clinical efficacy of endoscopic procedures for the treatment of adjacent segmental disease after lumbar fusion: A systematic review and meta-analysis

BACKGROUND

Adjacent segment disease (ASD) is a common complication after lumbar fusion and is still traditionally treated by open surgery. In recent years, with the development of minimally invasive techniques, percutaneous endoscopic surgery(PES) has been used for the treatment of ASD after lumbar fusion due to its unique benefits. Nevertheless, it remains unclear about its significant clinical efficacy and advantages over conventional open surgery.

OBJECTIVES

To evaluate the clinical efficacy and safety of PES in the treatment of ASD after lumbar fusion.

STUDY DESIGN

A systematic review and meta-analysis studies about the role of PES in managing ASD after lumbar fusion.

METHODS

A systematic search review was conducted in PubMed, EMBASE, Cochrane Library, Web of Science, CNKI, VIP, WanFang, and SinoMed databases from the start of their construction to 15 November 2021. Eligible studies included references to clinical trials of PES for ASD after open lumbar fusion. Observations included pain relief, recovery of postoperative function, overall excellent rates, and indicators of the advantages of minimally invasive surgery compared to conventional surgery. Postoperative complications and recurrence rates were also recorded.

RESULTS

A total of 24 studies, including 20 single-arm studies and 4 clinical control studies, all involving 928 patients were included. A total of 694 patients were included in the single-arm analysis. The results of the single-arm meta-analysis showed that PES could significantly reduce low back and leg pain and improve the functional status of the lumbar spine in patients with ASD after open lumbar fusion compared to preoperatively, and had good clinical efficacy after surgery. A total of 234 patients were included in the four clinically controlled studies, and the results of the meta-analysis showed that PES could clearly reduce pain and improve lumbar function, with no significant difference in efficacy between PES and open surgery. However, PES has a lower surgical incision, less intraoperative bleeding, and shorter operative time and length of hospital stay compared to open surgery. Moreover, it has a lower rate of postoperative recurrence as well as complications and a longer duration of efficacy.

CONCLUSIONS

On the basis of the available clinical literature and the results of this study, PES could achieve satisfactory clinical effects in ASD treatment after lumbar fusion. Compared with conventional open surgery, PES can not only obtain similar clinical results, but also had the advantages of less trauma and faster recovery. Nevertheless, a randomized controlled study is still needed to validate the findings of this study.

TRIAL REGISTRATION

Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022298387.

Transforaminal Endoscopic Decompression for Foraminal Stenosis: Single-Arm Meta-Analysis and Systematic Review

OBJECTIVE

The objective of the study was to conduct a single-arm meta-analysis and comprehensive systematic review to identify the efficacy and safety of transforaminal endoscopic surgery for the treatment of lumbar foraminal stenosis (LFS).

METHODS

The meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. The PubMed, Web of Science, and Embase databases were searched from inception to February 20, 2022. Primary research results were visual analog scale scores, Oswestry Disability Index scores, MacNab criterion scores, and reported adverse events. Subgroup analyses were performed on the primary outcome to evaluate the potential effects of several clinical factors that affected the results.

RESULTS

Of the 2020 studies identified, 9 met the inclusion criteria, and 316 participants were eligible for meta-analysis. The meta-analysis results found that transforaminal endoscopic surgery for the treatment of LFS was associated with a significant improvement in postoperative 12-month clinical indicators: 8 studies reported improvements in visual analog scale scores: -5.38, Oswestry Disability Index scores: -40.44, and MacNab criterion scores: odds ratio = 0.86; 8 studies reported 11.53% adverse events occurred in a total of 295 patients, and the most commonly reported event was transient postoperative dysesthesia, which occurred in 26 patients in a total of 6 studies with 240 patients (10.83%).

CONCLUSIONS

Transforaminal endoscopic surgery positively affects postoperative LFS patients' clinical indicators; however, high-level literature with randomized controlled trials is needed to confirm this technique's applicability in LFS.

Treatment of adjacent segment disease with percutaneous transforaminal endoscopic discectomy: Early experience and results

PURPOSE

Adjacent segment disease (ASD) constitutes a long-term complication of instrumented spinal fusion. Aim of this study is to analyze the utilization of percutaneous transforaminal endoscopic discectomy (PTED) for the treatment of symptomatic ASD, emphasizing basically in the postoperative course.

METHODS

A prospective study with 35 patients was designed. Patients enrolled in our study were distributed in two different groups. Group A constituted of 15 patients featuring ASD as a complication of a previously conducted lumbar spinal fusion. Group B was composed of 20 patients, presenting simple lumbar disc herniation (LDH). All patients were subjected to successful PTED for LDH. Patients were evaluated at regular intervals in 6-week and 3-, 6-, and 12-month postoperatively. Visual analog scale was utilized for leg (VAS-LP) and low back pain (VAS-BP) evaluation. Health-related quality of life was assessed with short-form 36 health survey questionnaire (SF-36).

RESULTS

VAS-BP scores were statistically significantly differentiated between the two groups in all intervals of follow-up. In contrast, VAS-LP scores demonstrated statistically significant differentiation in none of follow-up intervals, indicating similar results between the two groups. Maximal improvement was in both cases for all patients observed in 6-week postoperatively, with subsequent stabilization. SF-36 preoperative evaluation denoted a statistically significant differentiation in bodily pain and role emotional parameters, which was continually until the end of follow-up observed. The other SF-36 parameters featured similar values between the two groups preoperatively as well as during the follow-up intervals.

CONCLUSION

PTED is capable of successfully dealing with LDH and furthermore with complications of fusion as ASD.

A less invasive treatment by a full-endoscopic spine surgery for adjacent segment disease after lumbar interbody fusion

Background

Full-endoscopic spine surgery (FESS) is a suitable treatment for lumbar disc herniation (LDH) and foraminal stenosis. This study investigated the usefulness of FESS in treating adjacent segment disease (ASD) after lumbar interbody fusion (LIF).

Methods

Between September 2015 and March 2019, a total of 13 patients with symptomatic ASD after LIF underwent FESS. Discectomy and foraminoplasty using a 3.5-mm diameter high-speed drill were performed for treating LDH and foraminal stenosis. Preoperative and postoperative statuses were evaluated using Numerical Rating Scale (NRS) and the modified Japanese Orthopedic Association (mJOA) scores.

Results

The patients' mean age was 64.8 years; there were 10 male and 3 female patients. The mean operative time was 52.7 min. The mean pre- and postoperative NRS scores were 7.6 and 3.1, respectively. The mean pre- and postoperative mJOA scores were 10.5 and 16.1, respectively, and the mean recovery rate was 32.8%. Subsequent operative treatments were required in 3 patients for postoperative complication, insufficient decompression, and recurrence LDH.

Conclusions

FESS is a safe and effective minimally invasive treatment for ASD after LIF and a potential alternative to extend the LIF to the adjacent vertebra or sacrum.

Comparison of effectiveness and safety between epidural anesthesia vs local anesthesia for percutaneous transforaminal endoscopic discectomy: A systematic review and meta-analysis

OBJECTIVES

To compare the effectiveness and safety of epidural anesthesia (EA) with those of local anesthesia (LA) for percutaneous transforaminal endoscopic discectomy (PTED) and provide reference data for clinical decision-making.

METHODS

We searched PubMed, Embase, the Cochrane library, Web of Science, Medline, ScienceDirect, and the China National Knowledge Infrastructure from inception to June 2019 in order to identify randomized and nonrandomized controlled trials comparing EA and LA for PTED. Studies assessing at least 2 of the following indicators were eligible: surgical duration, X-ray exposure time, satisfaction rate, visual analog scale (VAS) scores for pain, Oswestry Disability Index (ODI), and complications. Two assessors evaluated the quality of the literature using the Cochrane Handbook or Newcastle-Ottawa Scale. Meta-analysis was conducted using Review Manager 5.3.3 software.

RESULTS

Four randomized controlled trials and 4 retrospective cohort studies involving a total of 1000 patients were included. The LA and EA groups included 473 and 527 patients, respectively. Meta-analysis revealed significant intergroup differences in the intraoperative (P < .00001) and postoperative (P < .00001) lumbar VAS scores, intraoperative (P < .00001) and postoperative (P = .001) leg VAS scores, and anesthesia satisfaction rate (P < .00001), with EA being superior to LA in all aspects. There were no significant intergroup differences in the surgical duration, X-ray exposure time, postoperative ODI, and complication rate.

CONCLUSION

EA is as safe as LA and produces better anesthetic effects than does LA in patients undergoing PTED. Therefore, it should be promoted as a reliable anesthetic technique for PTED.

Reducing the extent of facetectomy may decrease morbidity in failed back surgery syndrome

Background

Percutaneous transforaminal endoscopic discectomy (PTED) is widely used for the treatment of lumbar disc herniation. Facetectomy in PTED is necessary for accessing the intraspinal region and for decompressing the exiting nerve roots in patients who suffer from hypertrophy of the facet joints. However, this may increase morbidity in failed back surgery syndrome (FBSS) and has not been clearly elucidated.

Methods

A three-dimensional lumbosacral model was reconstructed and validated. And corresponding models after PTED with one-quarter and one-half excisions of the superior articular process were reconstructed. The maximum shear stress on the annulus in L5, von Mises stress of the facet cartilage, maximum principle capsular strain and deformation of the lumbosacral model were calculated using finite element methods.

Results

Calculated results show no significant differences in the complete model and the model with one-quarter excision of the superior articular process, but all biomechanical indexes have been deteriorated under most of the loading conditions tested in the model with one-half excision of the superior articular process.

Conclusions

Less facetectomy is better because it may reduce the risk of biomechanical deterioration and consequently, that of FBSS.

Percutaneous Endoscopic Lumbar Foraminotomy for Foraminal Stenosis with Postlaminectomy Syndrome in Geriatric Patients

INTRODUCTION

Postlaminectomy syndrome (PLS) or failed back surgery syndrome is a condition characterized by persistent pain following a back surgery. Degenerative processes may result in foraminal stenosis development over time, even after a successful surgery. Percutaneous endoscopic lumbar foraminotomy (PELF) offers a minimally invasive means of treating foraminal stenosis after a back surgery. The objective of this study was to evaluate the outcomes of PELF for foraminal stenosis with PLS in geriatric patients.

METHODS

Two-year follow-up data were collected from 21 consecutive patients aged 65 years or older (mean age, 72.4 years) who underwent PELF for foraminal stenosis with PLS. Transforaminal endoscopic foraminal decompression was performed under local anesthesia. Outcomes were assessed using visual analog scale pain score, Oswestry Disability Index, and modified Macnab criteria.

RESULTS

Mean visual analog scale for leg pain improved from 8.48 at baseline to 3.33 at 6 weeks, 2.10 at 1 year, and 2.19 at 2 years after PELF (P < 0.01). Mean Oswestry Disability Index improved from 67.29 at baseline to 30.69 at 6 weeks, 22.50 at 1 year, and 20.81 at 2 years after PELF (P < 0.01). Based on the modified Macnab criteria, excellent or good results were obtained in 81.0% of patients and symptomatic improvements were obtained in 95.2% of patients.

CONCLUSIONS

The transforaminal endoscopic approach can provide a better access angle to achieve a sophisticated foraminal decompression with less facet and dural injury. Therefore, PELF under local anesthesia can be useful for PLS or postoperative foraminal stenosis in elderly patients.

Laser-assisted endoscopic lumbar foraminotomy for failed back surgery syndrome in elderly patients

Elderly patients with failed back surgery syndrome (FBSS) or post-laminectomy foraminal stenosis have a higher risk of perioperative morbidity with extensive revision surgery. Thus, there is a need for safer and less invasive surgical options, such as laser-assisted endoscopic lumbar foraminotomy (ELF). A pin-point laser beam can allow precise tissue ablation and dissection in fibrotic adhesion tissues while preventing normal tissue injury. The present study aimed to describe the surgical technique of laser-assisted ELF and to evaluate the clinical outcomes of elderly patients with FBSS. Two-year follow-up data were collected from 26 consecutive patients aged 65 years or older who were treated with laser-assisted ELF for FBSS. Full-endoscopic foraminal decompression was performed using a side-firing laser and mechanical instruments. The average age of the patients was 70.2 years (range, 65-83 years). The mean visual analog pain score for leg pain improved from 8.58 at baseline to 3.35 at 6 weeks, 2.19 at 1 year, and 2.35 at 2 years after ELF (P < 0.001). The mean Oswestry disability index improved from 65.93 at baseline to 31.41 at 6 weeks, 21.77 at 1 year, and 20.64 at 2 years after ELF (P < 0.001). Based on the modified Macnab criteria, excellent or good results were obtained in 84.6% patients and symptomatic improvements were obtained in 92.3%. Extensive revision surgery in elderly patients might cause significant surgical morbidities. Laser-assisted ELF under local anesthesia could be a safe and effective surgical alternative for such patients at risk.

Biomechanical role of osteoporosis affects the incidence of adjacent segment disease after percutaneous transforaminal endoscopic discectomy

Study design

Variation in the biomechanical characteristics of intervertebral discs adjacent to the segment disc after undergoing percutaneous transforaminal endoscopic discectomy (PTED) in models with normal and abnormal bone mineral density (BMD) was estimated using the finite element method.

Objective

The study investigated the change in the incidence of adjacent segment disease (ASD) after PTED in patients without and with osteoporosis.

Backgrounds

PTED has been widely used for treating lumbar disc herniation (LDH); changes in BMD will affect biomechanical characteristics, possibly leading to changes in the incidence of ASD after PTED. However, this issue remains largely unclear.

Methods

A non-linear, lumbosacral finite element model was reconstructed based on imaging data and validated using compared values computed by the current model from published and well-validated, in vitro biomechanical experiment studies. Corresponding PTED models with normal and abnormal BMDs were also reconstructed. Shear and von Mises stresses on the annulus fibrosis, the von Mises stress on the endplates in L5–S1 segment discs, and the total deformation of current lumbosacral models were computed in different body positions by changing loading conditions, including flexion, extension, left and right lateral bending, and axial rotation.

Results

In most loading conditions, biomechanical characteristics of the lumbosacral segment discs with normal BMDs after PTED slightly increased. However, in the PTED model with osteoporosis, most of the biomechanical characteristics dramatically increased.

Conclusion

Osteoporosis leads to the deterioration of biomechanical characteristics in the adjacent segment disc after PTED; this variation may also result in an increase in the incidence of ASD. However, further studies on the interactions between pathological changes are warranted.

Full Endoscopic Discectomy Using Transforaminal Endoscopic Spine System Technique: A Mini Review of Complications

Background:

Full Endoscopic Discectomy (FED) is a minimally invasive technique for the treatment of Lumbar Disk Herniation (LDH) with increasing popularity among surgeons in the recent years. This alternative to conventional procedures surgical approach is generally a safe and efficient technique possessing many advantages such as less soft tissue trauma, preservation of dorsal musculature, and reduced perioperative morbidity and rapid recovery. However, FED is associated with a number of complications such as postoperative dysesthesia, nerve root injury, and dural tears.

Methods:

Α search of PubMed, Google Scholar and Scopus electronic databases was used to revised the literature on complications of full endoscopic discectomy using transforaminal endoscopic spine system technique

Conclusion:

In this review complications associated with FED are analyzed, emphasizing on the potential beneficial role of Transforaminal Endoscopic Spine System (TESSYS) technique in reducing their frequency.