Is sequestrectomy a viable alternative to microdiscectomy? A systematic review of the literature

Discectomy versus sequestrectomy in the treatment of lumbar disc herniation: a systematic review and meta-analysis

BACKGROUND CONTEXT

Lumbar disc herniation (LDH) is a leading cause of low back pain (LBP) and leg pain and may require surgical treatment in case of persistent pain and/or neurological deficits. Conventional discectomy involves removing the herniated fragment and additional material from the disc space, potentially accelerating disc degeneration and contributing to chronic LBP. Conversely, by resecting the herniated fragment only, sequestrectomy may reduce postoperative LBP while increasing the risk of LDH recurrence.

PURPOSE

To compare discectomy versus sequestrectomy in terms of risk of reherniation, reoperation rate, complications, pain, satisfaction, and perioperative outcomes (operative time, blood loss, length of stay [LOS]).

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A systematic search of PubMed/MEDLINE and Scopus databases was performed through May 1, 2024 for both randomized and nonrandomized studies. The search was conducted according to PRISMA guidelines. The RoB-2 and MINORS tools were utilized to assess the risk of bias in included studies. The quality of the evidence was evaluated according to the GRADE approach. Relevant outcomes were pooled for meta-analysis.

RESULTS

A total of 16 articles (1 randomized controlled trial with 2 follow-up studies, 6 prospective studies, and 7 retrospective studies) published between 1991 and 2020 involving 2009 patients were included for analysis. No significant differences were noted between discectomy versus sequestrectomy in terms of risk of reherniation (OR: 0.85, 95% CI: 0.57 to 1.26, p=.42), reoperation rate (OR: 0.95, 95% CI: 0.64 to 1.40, p=.78), and complications (OR: 1.03, 95% CI: 0.50 to 2.11, p=.94). Although LBP (MD: -0.06, 95% CI: -0.39 to 0.28, p=.74) and leg pain intensity (MD: 0.11, 95% CI: -0.21 to 0.42, p=.50) were similar postoperatively, significantly better outcomes were reported by patients treated with sequestrectomy at 1 year (leg pain: MD: 0.37, 95% CI: 0.19 to 0.54, p<.0001) and 2 years (LBP: MD: 0.19, 95% CI: 0.03 to 0.34, p=.02; leg pain: MD: 0.20, 95% CI: 0.09 to 0.31, p=.0005). Sequestrectomy also resulted in a higher patient satisfaction (OR: 0.60, 95% CI: 0.40 to 0.90, p=.01) and shorter operative time (MD: 8.71, 95% CI: 1.66 to 15.75, p=.02), while blood loss (MD: 0.18, 95% CI: -2.31 to 2.67, p=.89) and LOS (MD: 0.02 days, 95% CI: -0.07 to 0.12, p=.60) did not significantly differ compared to discectomy.

CONCLUSIONS

Based on the current evidence, discectomy and sequestrectomy do not significantly differ in terms of risk of reherniation, reoperation rate, and postoperative complications. Patients treated with sequestrectomy may benefit from a marginally higher pain improvement, better satisfaction outcomes, and a shorter operative time, although the clinical relevance of these differences needs to be validated in larger, prospective, randomized studies.

Role of surgery in primary lumbar disk herniation: WFNS spine committee recommendations

Objective

To provide the most up-to-date recommendations on the role of surgery in first-time lumbar disk herniations (LDH) in order to standardize surgical management.

Methods

We performed a literature search in PubMed, Scopus, and Embase from 2012 to 2022 using the following keywords: "lumbar disk herniation AND surgery". Our initial search yielded 2610 results, which were narrowed down to 283 papers after standardized screening critera were applied. The data from these 283 papers were presented and discussed at two international meetings of the World Federation of Neurosurgical Societies (WFNS) Spine Committee, where the Delphi method was employed and ten spine experts voted on five final consensus statements.

Results

and Conclusions: The WFNS Spine Committee's guidelines cover four main topics: (1) role and timing of surgery in first-time LDH; (2) role of minimally invasive techniques in LDH; (3) extent of disk resection in LDH surgery; (4) role of lumbar fusion in the context of LDH. Surgery for LDH is recommended for failure of conservative treatment, cauda equina syndrome, and progressive neurological impairment, including severe motor deficits. In the latter cases, early surgery is associated with faster recovery and may improve patient outcomes. Minimally invasive techniques have short-term advantages over open procedures, but there is insufficient evidence to make a recommendation for or against the choice of a specific surgical procedure. Sequestrectomy and standard microdiscectomy demonstrated similar clinical results in terms of pain control, recurrence rate, functional outcome, and complications at short and medium-term follow-up. Lumbar fusion is not recommended as a routine treatment for first-time LDH, although it may be considered in specific patients affected by chronic axial pain or instability.

Treatment of L5-S1 Floating Calcified Lumbar Disc Herniation with Percutaneous Endoscopic Interlaminar Discectomy

OBJECTIVE

The floating calcified tissue in floating calcified lumbar disc herniation (FCLDH) is hard and often adheres to the dura mater, which can easily cause nerve root damage during surgery, making the operation challenging. We proposed the classification of FCLDH and a new technique for removing floating calcified tissue and reported the clinical efficacy and safety of this new technique in clinical practice.

METHODS

From January 2019 to October 2021, 24 patients (13 males and 11 females, 46.4 ± 7.72 years) with L5-S1 floating calcified lumbar disc herniation were treated with percutaneous endoscopic interlaminar discectomy (PEID). According to FCLDH classification, a total of Type Ia: nine cases, Type Ib: five cases, Type IIa: four cases, and Type IIa: six cases were included. The visual analogue scale (VAS) and Oswestry disability index (ODI) were recorded pre-operatively and 3 days postoperatively, 6 months postoperatively, and at the last follow-up. The postoperative curative effect was evaluated according to the modified MacNab criteria. Computed tomography (CT) and magnetic resonance imaging (MRI) of the lumbar spine were performed 3 days after surgery to evaluate the efficacy of the surgery.

RESULTS

All patients successfully underwent PEID. The VAS and ODI scores at 3 days postoperatively, 6 months postoperatively, and at the last follow-up were significantly improved and statistically significant compared to those of the preoperative period (p < 0.05). All the patients were followed up for 12-24 months (mean, 16.6 ± 4.6 months). At the last follow-up, according to the modified MacNab criteria, 15 cases were excellent, eight were good, and one was fair. The combined excellent and good rate was 95.83% (23/24). Postoperative review revealed that all floating calcified tissues were effectively removed and the nerve roots were adequately decompressed without complications such as cerebrospinal fluid leakage and lumbar spine infection.

CONCLUSION

The classification of FCLDH we proposed can well guide the selection of surgical plans. PEID combined with floating calcified tissue removal technology has good efficacy in the treatment of L5-S1 FCLDH, ensuring accurate removal of calcified tissue, reducing complications and improving the quality of life of affected individuals.

Evaluation of Spin in Systematic Reviews and Meta-Analyses of Minimally Invasive Surgical Techniques and Standard Microdiscectomies for Treating Lumbar Disc Herniation

STUDY DESIGN

Systematic review.

OBJECTIVES

Spin in scientific literature is defined as bias that overstates efficacy and/or underestimates harms of procedures undergoing review. While lumbar microdiscectomies (MD) are considered the gold standard for treating lumbar disc herniations (LDH), outcomes of novel procedures are being weighed against open MD. This study identifies the quantity and type of spin in systematic reviews and meta-analyses of LDH interventions.

METHODS

A search was conducted on the PubMed, Scopus, and SPORTDiscus databases for systematic reviews and meta-analyses evaluating the outcomes of MD against other LDH interventions. Each included study's abstract was assessed for the presence of the 15 most common types of spin, with full texts reviewed during cases of disagreement or for clarification. Full texts were used in the assessment of study quality per AMSTAR 2.

RESULTS

All 34 included studies were observed to have at least 1 form of spin, in either the abstract or full text. The most common type of spin identified was type 5 ("The conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studies"), which was observed in ten studies (10/34, 29.4%). There was a statistically significant association between studies not registered with PROSPERO and the failure to satisfy AMSTAR type 2 (P < .0001).

CONCLUSION

Misleading reporting is the most common category of spin in literature related to LDH. Spin overwhelmingly tends to go in the positive direction, with results inappropriately favoring the efficacy or safety of an experimental intervention.

Changes in Disc Height as a Prognostic Factor in Patients Undergoing Microscopic Discectomy

OBJECTIVE

Some patients with disc herniation who underwent discectomy complain of back pain after surgery and are unsatisfied with the surgical results. This study aimed to evaluate the relationship between preoperative disc height (DH), postoperative DH, and pain score 12 months after surgery in patients who underwent microdiscectomy for herniated lumbar disc.

METHODS

This study enrolled patients who underwent microdiscectomy at a medical center between January 2012 and December 2020. Patients with X-ray or computed tomography and pain score assessment (visual analog scale score) prior to surgery, immediately post-op, and at 1, 6, and 12 months after surgery were included. The DH index was defined as DH/overlying vertebral width. The DH ratio was defined as the postoperative DH/preoperative DH. Simple linear regression and multivariate linear regression analyses were applied to assess the correlation between DHs and leg pain scores 12 months after surgery.

RESULTS

A total of 118 patients who underwent microdiscectomy were included. DH decreased up to 12 months after surgery. The DH ratio at 1, 6, and 12 months after discectomy showed a significant positive correlation with the pain scores at 12 months after discectomy (1 month : p=0.045, B=0.52; 6 months : p=0.008, B=0.78; 12 months : p=0.005, B=0.69). Multivariate linear regression analysis revealed that the level of surgery, sex, age, and body mass index had no significant relationship with back pain scores after 12 months.

CONCLUSION

In patients who underwent microdiscectomy, the DH ratios at 1, 6, and 12 months after surgery were prognostic factors for back pain scores at 12 months after surgery. Aggressive discectomy is recommended for lower postoperative DH ratios and Visual analog scale scores, leading to improved patient satisfaction.

Surgical techniques and perioperative surgical outcomes after discectomy for calcified lumbar disc herniation: a review and meta-analysis

INTRODUCTION

Calcified lumbar disc herniation (CLDH) poses surgical challenges due to longstanding disease and adherence of herniated disc to the surrounding neural structures. The data regarding outcomes after surgery for CLDH are limited. This review was conducted to analyse the surgical techniques, perioperative findings and the postoperative clinical outcomes after surgery for CLDH.

METHODS

PRISMA guidelines were followed whilst conducting this systematic review and meta-analysis. The literature review was conducted on 3 databases (PubMed, EMBASE, and CINAHL). After thorough screening of all search results, 9 studies were shortlisted from which data were extracted and statistical analysis was done. Pooled analysis was done to ascertain the perioperative and postoperative outcomes after surgery for CLDH. Additional comparative analysis was done compared to CLDH with non-calcified lumbar disc herniation (NCLDH) cases.

RESULTS

We included 9 studies published between 2016 and 2022 in our review, 8 of these were retrospective. A total of 356 cases of CLDH were evaluated in these studies with a male preponderance (56.4%). Mean operative time was significantly lower in NCLDH cases compared to CLDH cases. The mean estimated blood loss showed a negative correlation with the percentage of males. Satisfactory clinical outcomes were observed in majority of patients. The risk of bias of the included studies was moderate to high.

CONCLUSION

Surgical difficulties in CLDH cases leads to increase in operative time compared to NCLDH. Good clinical outcomes can be obtained with careful planning; the focus of surgery should be on decompression of the neural structures rather than disc removal.

Factors associated with the recurrence of lumbar disk herniation: non-biomechanical-radiological and intraoperative factors

BACKGROUND

Recurrent lumbar disk herniation (RLDH) is one of the most undesirable complications following lumbar discectomy (LD). This study aimed to prospectively investigate the non-biomechanical-radiological and intraoperative factors affecting the recurrence after discectomy.

PATIENTS AND METHODS

Data of 988 consecutive patients with Lumbar disk herniation (LDH) who underwent LD at our department for over 2 years (2014-2015) were prospectively collected. Patients who met our study criteria were included (n = 816). Patients were divided into the following groups; group 1 included patients with symptomatic RLDH within the first postoperative 2 years (PO24M), group 2 included patients with symptomatic RLDH after PO24M, and group 3 included patients without symptomatic RLDH/LDH. The preoperative non-biomechanical-radiological, surgical, and intraoperative characteristics were compared among the groups.

RESULTS

A total of 842 LDHs in 816 (386 men and 430 women) patients received LD. The mean age was 46.9 years. The mean follow-up period was 72.8 months. The first recurrence rates within the first PO24M and after PO24M were 7.1% and 3.2%, respectively. Disks with Modic changes type-II and contained disks without fragments were associated with the short- and long-term RLDH [(p = 0.004; HR = 0.6); (p < 0.0001; HR = 0.14)] and [(p = 0.041; HR = 0.6); (p < 0.0001; HR = 0.16)], respectively.

CONCLUSIONS

Several radiological, surgical, and intraoperative factors can play a critical role in RLDH; therefore, the selection criteria of patients with LDH should be carefully considered for surgical treatment to obtain acceptable outcomes.

ABBREVIATIONS

ANOVA: A one-way analysis of variance, CIs: 95% confidence intervals, HR: Hazard ratio, LD: Lumbar discectomy, LDH: Lumbar disc herniation, LF: ligamentum flavum, MRI: Magnetic resonance imaging, MC-I: Modic changes type I, MC-II: Modic changes type II, MC-III: Modic changes type III, n: Number, ODI: Oswestry Disability Index, OR: Odds ratio, p-value: Probability value, PO: Postoperative, Pre: Preoperative, Pts: Patients, RLDH: Recurrent lumbar disc herniation, RR: Relative/risk ratio, SPSS: Statistical package for the social science, T1WIs: T1-weighted images, T2WIs: T2-weighted images, VAS: Visual analog scale.

Clinical Trial Registry Use in Orthopaedic Surgery Systematic Reviews

BACKGROUND

Results from systematic reviews and meta-analyses, which have the highest level of evidence (Level I), often drive clinical decision-making and health policy. Often, unpublished trial data are omitted from systematic reviews, raising concerns about the extent of the reliability and validity of results that have been drawn from systematic reviews. We aimed to determine the extent to which systematic review authors include searches of clinical trial registries for unpublished data when conducting systematic reviews in orthopaedic surgery.

METHODS

Systematic reviews and/or meta-analyses were gathered from the top 5 orthopaedic surgery journals based on the h5-index from Google Scholar Metrics. Systematic reviews that had been published in the Cochrane Database of Systematic Reviews, which requires the inclusion of a clinical trial registry search, served as controls. For the primary outcome, each systematic review from the top 5 orthopaedic journals was screened to determine whether the authors of each study searched for unpublished data in clinical trial registries. We then compared the rate of registry searches with those in the control group. For the secondary analysis, a search of ClinicalTrials.gov was performed for unpublished trial data for 100 randomized systematic reviews.

RESULTS

All 38 of the Cochrane systematic reviews (100%) included clinical trial registry searches, while the top 5 orthopaedic journals had only 31 of 480 studies (6.5%) that looked at clinical trial registries. The secondary analysis yielded 59 of 100 systematic review articles (59.0%) that could have included unpublished clinical trial data from ≥1 studies to their sample.

CONCLUSIONS

Systematic reviews that have been published in the top orthopaedic surgery journals seldom included a search for unpublished clinical trial data.

CLINICAL RELEVANCE

The exclusion of clinical trial registry searches potentially contributes to publication bias within the orthopaedic literature. Moving forward, systematic review authors should include clinical trial registry searches for unpublished clinical trial data to provide the most accurate representation of the available evidence for systematic reviews and meta-analyses.

Technical Considerations of Interlaminar Approach for Lumbar Disc Herniation

With the evolution of endoscopic instruments and techniques, full-endoscopic spine surgery has attracted more attention worldwide in recent years. At the initial stage, surgeons conducted endoscopic lumbar discectomy using the transforaminal approach. Next, interlaminar endoscopic lumbar discectomy was developed to treat a herniation disc at the L5-S1 level. The progression in interlaminar endoscopic techniques has further broadened the indications for full-endoscopic spine surgery. However, the steep learning curve of endoscopic procedures has remained challenging. The use of interlaminar endoscopic lumbar discectomy entails many essential skills to manage the different anatomical structures of the spine. From the perspective of successful and safe interlaminar endoscopic lumbar discectomy, we have discussed the technical considerations for endoscopic procedures.

Brake reaction time before and after surgery for patients with sequestrectomy versus conventional microdiscectomy

The aim of this study was to compare the effects of sequestrectomy versus conventional microdiscectomy on breaking response time (BRT) for lumbar disc herniation (LDH). BRT is the key factor for return to drive recommendations after surgery. A prospective clinical study was conducted. Patients aged 25-65 years who underwent surgery for lumbar disc herniation and held a valid motorcar driving license were recruited in a single institution. The patients were assessed before surgery, immediately after the surgery and at the follow up examination 30 days post-surgery. BRT was measured using a driving simulator, a visual analogue scale (VAS) was used for pain assessment. BRT values were compared with BRT values of a healthy control group. In patients treated with microdiscectomy BRT reduced from 749 (±223) msec before surgery to 649 (±223) msec immediately after the surgery. In the sequestrectomy group BRT reduced from 852 (±561) msec before surgery to 693 (±173) msec immediately after the surgery. BRT at follow up was 610 (±145) msec for patients treated with microdiscectomy and 630 (±98) msec for patients operated with sequestrectomy. BRT for healthy controls was 487 (±116) msec. Pain improved significantly for both patient samples. Sequestrectomy and microdiscectomy were associated with similar effects on pain and BRT after surgery. There was no statistically significant difference between BRT of both patient samples at 30 days follow up examination. Both surgical techniques showed a positive effect on BRT. No statistically significant difference between sequestrectomy and microdiscectomy on BRT could be found.

Closing the Treatment Gap for Lumbar Disc Herniation Patients with Large Annular Defects: A Systematic Review of Techniques and Outcomes in this High-risk Population

Lumbar disc herniation (LDH) is one of the most common spinal pathologies and can be associated with debilitating pain and neurological dysfunction. Discectomy is the primary surgical intervention for LDH and is typically successful. Yet, some patients experience recurrent LDH (RLDH) after discectomy, which is associated with worse clinical outcomes and greater socioeconomic burden. Large defects in the annulus fibrosis are a significant risk factor for RLDH and present a critical treatment challenge. It is essential to identify reliable and cost-effective treatments for this at-risk population. A systematic review of the PubMed and Embase databases was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify studies describing the treatment of LDH patients with large annular defects. The incidence of large annular defects, measurement technique, RLDH rate, and reoperation rate were compiled and stratified by surgical technique. The risk of bias was scored for each study and for the identification of RLDH and reoperation. Study heterogeneity and pooled estimates were calculated from the included articles. Fifteen unique studies describing 2,768 subjects were included. The pooled incidence of patients with a large annular defect was 44%. The pooled incidence of RLDH and reoperation following conventional limited discectomy in this population was 10.6% and 6.0%, respectively. A more aggressive technique, subtotal discectomy, tended to have lower rates of RLDH (5.8%) and reoperation (3.8%). However, patients treated with subtotal discectomy reported greater back and leg pain associated with disc degeneration. The quality of evidence was low for subtotal discectomy as an alternative to limited discectomy. Each report had a high risk of bias and treatments were never randomized. A recent randomized controlled trial with 550 subjects examined an annular closure device (ACD) and observed significant reductions in RLDH and reoperation rates (>50% reduction). Based on the available evidence, current discectomy techniques are inadequate for patients with large annular defects, leaving a treatment gap for this high-risk population. Currently, the strongest evidence indicates that augmenting limited discectomy with an ACD can reduce RLDH and revision rates in patients with large annular defects, with a low risk of device complications.

A Pilot Study of Percutaneous Interlaminar Endoscopic Lumbar Sequestrectomy: A Modern Strategy to Tackle Medically-Refractory Radiculopathies and Restore Spinal Function

Objective

Angled scopes allow 360° visualization, which makes percutaneous endoscopic techniques (percutaneous endoscopic lumbar discectomy, PELD) particularly attractive for sequestrectomies, which entail the removal of extruded lumbar disc fragments that have migrated caudally or cranially between the ligaments, foramina, and neural structures, while preserving the disc. Although many different PELD techniques are currently available, not all of them are suitable for sequestrectomies; furthermore, long-term follow-up data are unfortunately lacking.

Methods

A pilot study was conducted on a cohort of 270 patients with lumbar radiculopathy undergoing minimally invasive spine surgery (PELD or microdiscectomy), of whom only 7 were eligible for endoscopic interlaminar sequestrectomy with disc preservation. The patients’ baseline conditions and clinical outcomes were measured with the Oswestry Disability Index and a visual analogue scale. Long-term follow-up was conducted using satisfaction questionnaires that were based on the MacNab criteria and administered by medical/nursing personnel not involved in their primary surgical management.

Results

EasyGo system was eventually used in 5 PELD cases. No dural tears, infections, or nerve root injuries were recorded in patients undergoing sequestrectomy. Surgical events, including blood loss and overall length of hospital stay, did not differ significantly among the 270 patients. In the group treated with endoscopic sequestrectomy, no recurrences or complications were noted during a follow-up of 3 years, and an excellent degree of satisfaction was reported.

Conclusion

We provide OCEBM (Oxford Centre for Evidence-Based Medicine) level 3 evidence that interlaminar endoscopic sequestrectomy is a tailored and well-tolerated surgical option; nonetheless, a cost-effectiveness analysis assessing the interval until return to working activities and long-term benefits is warranted.

Recurrent lumbar disc herniation: Is there a correlation with the surgical technique? A multivariate analysis

Purpose

The recurrence of a lumbar disc herniation (LDH) is a common cause of poor outcome following lumbar discectomy. The aim of this study was to assess a potential relationship between the incidence of recurrent LDH and the surgical technique used. Furthermore, we tried to define the best surgical technique for the treatment of recurrent LDH to limit subsequent recurrences.

Materials and Methods

A retrospective study was conducted on 979 consecutive patients treated for LDH. A multivariate analysis tried to identify a possible correlation between (1) the surgical technique used to treat the primary LDH and its recurrence; (2) technique used to treat the recurrence of LDH and the second recurrence; and (3) incidence of recurrence and clinical outcome. Data were analyzed with the Pearson's Chi-square test for its significance.

Results

In 582 cases (59.4%), a discectomy was performed, while in 381 (40.6%), a herniectomy was undertaken. In 16 cases, a procedure marked as "other" was performed. Among all patients, 110 (11.2%) had a recurrence. Recurrent LDH was observed in 55 patients following discectomy (9.45%), in 45 following herniectomy (11.8%), and in 10 (62.5%) following other surgery. Our data showed that 90.5% of discectomies and 88.2% of the herniectomies had a good clinical outcome, whereas other surgeries presented a recurrence rate of 62.5% (Pearson's χ²< 0.001). No statistical differences were observed between discectomy or herniectomy, for the treatment of the recurrence, and the incidence for the second recurrences (P > 0.05). A significant statistical correlation emerged between the use of other techniques and the incidence for the second recurrences (P < 0.05).

Conclusions

The recurrence of an LDH is one of the most feared complications following surgery. Although the standard discectomy has been considered more protective toward the recurrence compared to herniectomy, our data suggest that there is no significant correlation between the surgical technique and the risk of LDH recurrence.

The modified transforaminal endoscopic technique in treating intracanalicular combining foraminal and/or extraforaminal lumbar disc herniations

Background

To develop a modified transforaminal endoscopic spine system (TESSYS^®) technique for treating intracanalicular combining foraminal and/or extraforaminal lumbar disc herniation (ICFE-LDH), and evaluate the technical efficacy and safety.

Methods

Twenty-three patients with ICFE-LDH underwent the modified TESSYS technique were enrolled. Magnetic resonance imaging (MRI) was used to verify the reduction of herniated disc. Pre- and post-operative neurological functions were compared by visual analogue scale (VAS) score, Oswestry disability index (ODI) and the modified MacNab criteria. The technical safety was evaluated by surgical complications.

Results

MRI demonstrated reductions of disc herniations in 22 patients (95.7%) after surgeries. The VAS scores were significantly improved at 1 year follow-up (low back: P=0.001, lower limbs: P<0.001), as well as ODI scores (P<0.001). 22 patients had achieved excellent and good recovery postoperatively according to the modified MacNab criteria. One patient (4.3%) underwent a reoperation due to postoperative recurrence of disc herniation. Another patient complained postoperative causalgia in 8 weeks, the symptom alleviated after conservative treatment at 1 year follow-up (VAS: back, 3, lower limbs, 0; ODI: 20%). The incidence rate of surgical complication was 8.7%.

Conclusions

The modified TESSYS technique is a minimally-invasive, effective and safe surgery for treating ICFE-LDHs in selected patients.

Lumbar disc reherniation after transforaminal lumbar endoscopic discectomy

Background

Transforaminal lumbar endoscopic discectomy is a minimally invasive surgical procedure that can be performed in awake patients through an incision less than 1 cm. The procedure requires very little bony removal to access the herniated disc material because the approach is through the foramen, and only a small amount of the superior articulating process is removed to access Kambin's triangle. This study describes our experience with transforaminal endoscopic lumbar decompression (TELD) for the treatment of lumbar disc herniation. We evaluate the risk for reherniation in the first year after surgery and the characteristics of the patients who experience reherniation.

Methods

We describe the technique for the transforaminal endoscopic approach to treat lumbar disc herniations. Retrospectively, a series of 141 consecutive patients, who were operated on with lumbar radiculopathy, was analyzed. We excluded patients who had previous surgery at the lumbar level, surgeries done for disease adjacent to a fusion, and surgeries done for spondylolisthesis. A total of 84 consecutive patients were included who had single level lumbar non-revision surgery and at least 1-year follow up.

Results

A series of 46 consecutive male and 38 female patients with an average age of 57.4 years (range, 28-87 years old) who underwent transforaminal endoscopic treatment for lumbar disc herniations between 2014 and 2016 is presented. Four patients required microdiscectomy due to reherniation at 5 months, 8 months, 9 months, and 10 months postoperatively. All the patients in the series improved immediately following their endoscopic procedures, and no patients presented with symptoms suggestive of reherniation until 5 months after their initial endoscopic surgery. Patients with reherniation tended to be young: 31, 45, 48, and 49 years of age: all less than the average patient age who underwent endoscopic surgery.

Conclusions

Transforaminal endoscopic surgical access to lumbar disc herniations is an ultra-minimally invasive approach for the treatment lumbar degenerative disc disease. It allows for neural decompression by removing disc and foraminal pathology with minimal bone removal. This minimal bone removal prevents iatrogenic destabilization. However, the 1-year reherniation rate presented here is 4.7%. This suggests that the benefit of this technique may be that it is ultra-minimally invasive, but it may only be equal, not superior to microdiscectomy in its rate of reherniation.

Development of a bovine decellularized extracellular matrix-biomaterial for nucleus pulposus regeneration

Painful intervertebral disc (IVD) degeneration is a common cause for spinal surgery. There is a clinical need to develop injectable biomaterials capable of promoting IVD regeneration, yet many available biomaterials do not mimic the native extracellular matrix (ECM) or promote matrix production. This study aimed to develop a decellularized injectable bovine ECM material that maintains structural and compositional features of native tissue and promotes nucleus pulposus (NP) cell (NPC) and mesenchymal stem cell (MSC) adaption. Injectable decellularized ECM constructs were created using 3 NP tissue decellularization methods (con.A: sodium deoxycholate, con.B: sodium deoxycholate & sodium dodecyl sulfate, con.C: sodium deoxycholate, sodium dodecyl sulfate & TritonX-100) and evaluated for protein, microstructure, and for cell adaptation in 21 day human NPC and MSC culture experiments. Con.A was most efficient at DNA depletion, preserved best collagen microstructure and content, and maintained the highest glycosaminoglycan (GAG) content. NPCs in decellularized constructs of con.A&B demonstrated newly synthesized GAG production, which was apparent from "halos" of GAG staining surrounding seeded NPCs. Con.A also promoted MSC adaption with high cell viability and ECM production. The injectable decellularized NP biomaterial that used sodium deoxycholate without additional decellularization steps maintained native NP tissue structure and composition closest to natural ECM and promoted cellular adaptation of NP cells and MSCs. This natural decellularized biomaterial warrants further investigation for its potential as an injectable cell seeded supplement to augment NP replacement biomaterials and deliver NPCs or MSCs. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:876-888, 2016.

Effect of a New Annular Incision on Biomechanical Properties of the Intervertebral Disc

OBJECTIVE

To compare the biomechanical properties of a novel annular incision technique, an oblique incision made approximately 60° to the spinal column, with the traditional transverse and longitudinal annular slit incision in an ex vivo sheep lumbar spine model.

METHODS

Sixteen sheep lumbar spines were used for the current ex vivo biomechanical comparative study. Functional spine unit (FSU) specimens composed of two vertebrae and one disc in the middle was cut from the whole lumbar spine. Annular slit incisions of 5 mm were made in different directions with a 15-blade knife at the intervertebral disc, following which partial discectomy was performed to produce the following groups: control with no incision, transverse slit, longitudinal slit and oblique slit groups. The specimens were then subjected to flexion-extension, lateral bending, axial rotation and compression tests.

RESULTS

As expected, the control group showed the least range of motion (ROM) in the flexion-extension test. The oblique slit group showed a trend toward a smaller ROM than the transverse and longitudinal groups in 1, 2, 3 and 5 Nm flexion-extension tests; these differences were not statistically significant (P > 0.05). In addition, the transverse (5.80° ± 0.20°), longitudinal (5.77° ± 0.67°) and oblique (5.47° ± 0.43°) slit groups showed a significantly larger ROM than the control group (3.22° ± 0.28°) in 2 Nm lateral bending tests (P < 0.05). Compared with the transverse and longitudinal groups, the oblique group also showed a trend toward a smaller ROM in lateral bending tests (P > 0.05). Following increments in the axial torsion force, the ROM was greater in all four experimental groups than the ROM with 1 Nm axial torsion. Furthermore, a significantly smaller axial rotational ROM was found in the oblique than the transverse group for 1 and 5 Nm force (P < 0.05). With increase in the axial force to 5 Nm, the ROM in the oblique slit group (4.71° ± 0.52°) was significantly smaller than that in the transverse group (7.25° ± 0.46°, P < 0.05), but not significantly different from that of the longitudinal slit group (5.84° ± 0.23°, P > 0.05). Comparable ultimate loads to failure were found in the oblique, transverse and longitudinal groups; the highest ultimate load to failure being in the control group (P > 0.05).

CONCLUSION

The novel oblique slit annular incision to the intervertebral disc showed a trend toward better biomechanical properties than the traditional transverse and longitudinal slit incisions.

Sequestrectomy Versus Conventional Microdiscectomy for the Treatment of a Lumbar Disc Herniation: A Systematic Review

STUDY DESIGN

A systematic review.

OBJECTIVE

The aim of this study was to compare the effects of sequestrectomy versus conventional microdiscectomy for lumbar disc herniation (LDH).

SUMMARY OF BACKGROUND DATA

Open surgery for LDH can be performed by sequestrectomy (removal of disc fragments) or conventional discectomy (removal of disc fragments and disc). Sequestrectomy might be associated with a higher risk of recurrence but less low back pain (LBP) after surgery.

METHODS

We searched MEDLINE and EMBASE from 1980 to November 2014. We selected randomized controlled trials (RCTs) and nonrandomized prospective studies of conventional discectomy versus sequestrectomy for adult patients with LDH that evaluated the following primary outcomes: radicular pain or LBP as measured by a visual analog scale, or neurological deficits of the lower extremity. We also evaluated the following secondary outcomes: complications of surgery, reherniation rate, duration of hospital stay, postoperative analgesic use, and health-related quality-of-life measures. Two authors independently reviewed citations and articles for inclusion. We assessed the risk of bias, synthesized data, and the level evidence using standard methodological procedures as recommended by the Cochrane Back Review Group.

RESULTS

We identified 5 studies (746 participants) of sequestrectomy versus microdiscectomy. One study was RCT and the other 4 were nonrandomized prospective comparisons; all studies were assessed as being at a high risk of bias. There were no significant differences for leg pain, LBP, functional outcomes, complications, and hospital stay or recurrence rate for 2 years (level of evidence: Low). Sequestrectomy was associated with less analgesic consumption versus discectomy (level of evidence: Very low).

CONCLUSION

Sequestrectomy and standard microdiscectomy were associated with similar effects on pain after surgery, recurrence rate, functional outcome, and complications; more evidence is needed to determine whether sequestrectomy is associated with less postoperative analgesic consumption.

LEVEL OF EVIDENCE

2.

Comparison of discectomy versus sequestrectomy in lumbar disc herniation: a meta-analysis of comparative studies

Background

Lumbar disc removal is currently the standard treatment for lumbar disc herniation. No consensus has been achieved whether aggressive disc resection with curettage (discectomy) versus conservative removal of the offending disc fragment alone (sequestrectomy) provides better outcomes. This study aims to compare the reherniation rate and clinical outcomes between discectomy and sequestrectomy by literature review and a meta-analysis.

Methods

A systematic search of PubMed, Medline, Embase and the Cochrane Library was performed up to June 1, 2014. Outcomes of interest assessing the two techniques included demographic and clinical baseline characteristics, perioperative variables, complications, recurrent herniation rate and post-operative functional outcomes.

Results

Twelve eligible trials evaluating discectomy vs sequestrectomy were identified including one randomized controlled study, five prospective and six retrospective comparative studies. By contrast to discectomy, sequestrectomy was associated with significantly less operative time (p<0.001), lower visual analogue scale (VAS) for low back pain (p<0.05), less post-operative analgesic usage (p<0.05) and better patients’ satisfaction (p<0.05). Recurrent herniation rate, reoperation rate, intraoperative blood loss, hospitalization duration and VAS for sciatica were without significant difference.

Conclusions

According to our pooled data, sequestrectomy entails equivalent reherniation rate and complications compared with discectomy but maintains a lower incidence of recurrent low back pain and higher satisfactory rate. High-quality prospective randomized controlled trials are needed to firmly assess these two procedures.