Surgical outcomes of full endoscopic spinal surgery for lumbar disc herniation over a 10-year period: A retrospective study

Long-term clinical efficacy of radioplaque gelified ethanol for lumbar disc herniation: a multicenter study

BACKGROUND AND PURPOSE

Degenerative and/or herniated discs are a global cause of chronic lower back and neck pain. While multiple treatments exist, the research for long-term effective interventions with minimal side effects continues. The radioplaque gelified ethanol (RGE) (DiscoGel®, Hérouville-Saint-Clair, France), is an addition to the armamentarium of potential treatments. This study aimed to evaluate the long-term efficacy of this device in treating lumbar disc herniation through a 10-year follow-up period.

METHODS

In this bi-centric observational study, patients treated with RGE in the lumbar spine between 2009 and 2011 were evaluated based on specific inclusion and exclusion criteria. Collected data encompassed preoperative imaging, VAS pain scores, ODI functional scores, were recorded through 10-year follow-up.

RESULTS

Fifty-two participants (26 males and 26 females) with an average age of 51.7 years were enrolled in the study. Ten years after treatment, there was a statistically significant improvement in VAS pain scores and ODI percentages (p < 0.01). Additionally, significant changes in anterior, medial, and posterior disc dimensions were observed, suggesting structural adaptations due to RGE treatment. A statistically significant difference in the anterior dimension of the treated disc was found 10 years postoperatively compared to preoperative measurements (p = 0.0011).

CONCLUSION

RGE is a promising therapeutic choice for lumbar symptomatic herniation resistant to conservative treatments, offering both immediate relief and enduring benefits. Although our findings are promising, additional randomized controlled trials are essential to compare DiscoGel® with established treatments and substantiate its efficacy.

Predictors and Postoperative Complication Risks for Revision Discectomies Following Primary Lumbar Microdiscectomy

STUDY DESIGN

Retrospective cohort analysis.

OBJECTIVE

Identify demographic and clinical predictors for revision discectomy and compare postoperative complications between primary microdiscectomy (MD) and revision discectomy.

METHODS

Patients who underwent one-level primary lumbar MD and subsequent one-level revision discectomy for lumbar disc herniation were identified using the PearlDiver national database. Multivariate regression analysis was performed to identify predictors of revision discectomy, assess 30-day postoperative complications and opioid use, and assess the likelihood of future lumbar fusion.

RESULTS

Of 52,310 patients undergoing primary lumbar MD, 4536 (7.98%) required revision. Independent predictors included smoking (aOR: 1.72), obesity (aOR: 1.44), lateral disc herniation (aOR: 1.69), coagulopathies (aOR: 1.34), CAD (aOR: 1.62), anemia (aOR: 1.38), diabetes (aOR: 1.47), hypertension (aOR: 1.63), peripheral vascular disease (aOR:1.33), preoperative opioid use (aOR: 2.06), postoperative opioid use (aOR: 1.80), and depression (aOR: 1.73) (all, P < 0.01). Revision discectomy was associated with higher risks of infection (aOR: 1.78), AKI (aOR: 1.41), VTE (aOR: 1.46), dehiscence (aOR: 2.32), neurological injury (aOR: 1.48), durotomy (aOR: 2.19), epidural hematoma (aOR: 2.61), I&D (aOR: 2.32), opioid use (aOR: 1.73), and increased fusion rates (all P < 0.05).

CONCLUSION

Several patient-related factors increase the risk of revision MD, which is associated with additional short- and long-term complication risks relative to the index procedure. These findings inform expectations for disease progression and postoperative outcomes in revision MD. Revision discectomy should be avoided when possible.

Which North American spine society disc herniation morphology descriptors are most associated with improvements in clinical outcomes after microdiscectomy?

Background

The North American Spine Society (NASS) assembled the first ever comprehensive naming system for describing lumbar disc disease, including lumbar disc herniation. The objectives of this study were (1) to determine which NASS descriptors are most predictive of independent patient-reported outcomes after microdiscectomy and (2) to identify the inter-rater reliability of each NASS descriptor.

Methods

Adult patients (≥18 years) who underwent a lumbar microdiscectomy from 2014-2021 were retrospectively identified. Patient-reported outcome measures (PROMs) were collected at preoperative, 3-month, and 1-year postoperative time points. Lumbar disc herniations were evaluated and classified on preoperative MRI using the NASS lumbar disc nomenclature specific to disc herniation.

Results

About 213 microdiscectomy patients were included in the final analysis. Herniation descriptors exhibiting the greatest reliability included sequestration status (κ=0.83), axial disc herniation area (κ=0.83), and laterality (κ=0.83). The descriptor with the lowest inter-rater reliability was direction of migration (κ=0.53). At 3 months, a sequestered herniation was associated with lower odds of achieving the minimal clinically important difference (MCID) for ODI (p=.004) and MCS (p=.032). At 12 months, a similar trend was observed for Oswestry Disability Index (ODI) MCID achievement (p=.001). At 3 months, a herniation with larger axial area was a predictor of MCID achievement in ODI (p=.004) and the mental component summary (MCS) (p=.009). Neither association persisted at 12 months; however, larger axial disc herniation area was able to predict MCID achievement in the Visual Analogue Scale (VAS) leg (p=.031) at 12 months.

Conclusions

The utility of the NASS nomenclature system in predicting postoperative outcomes after microdiscectomy has yet to be studied. We showed that sequestration status and disc area are both reliable and able to predict the odds of achieving MCID in certain clinical outcomes at 3 months and 12 months after surgery. Hence, preoperative imaging analysis of lumbar disc herniations may be useful in accurately setting patient expectations.

A narrative review of endoscopic spine surgery: history, indications, uses, and future directions

Background and Objective

The concept of endoscopic surgery began in the 1930s and has since undergone numerous advancements in both technology and surgical indications. Its main benefit is providing the opportunity to perform surgery while minimizing disruption to surrounding structures. The purpose of this review is to summarize the history, uses, and future directions for spine endoscopic surgery.

Methods

A review of national databases was performing using key terms "endoscopic", "spine" and "surgery" for literature from 1900 to 2023. Studies that aimed to describe the utilities of endoscopic surgeries, associated outcomes, limitations, and future directions were included. Studies that were not in English were excluded.

Key Content and Findings

This review includes a brief overview of the history of endoscopic surgery and its current two main approaches, transforaminal and interlaminar approaches. It then summarizes the main indications and utilization of endoscopic surgery in the lumbar, cervical and thoracic spine, as well as expansion in managing spine tumors, infections, and outpatient surgical cases.

Conclusions

There are many rising indications and uses for endoscopic spine surgery in nearly every aspect of the spine. Compared to conventional spine surgery, there is early evidence showing endoscopic surgery is associated with less post-operative pain, shorter hospital stays, and possibly quicker recovery times. As current trends in spine surgery move towards minimally invasive techniques, it is anticipated that the use of endoscopic surgery will continue to expand.

Effect of Glycemic Disorders and Habits on the Concentration of Selected Neurotrophic Factors in Patients with Lumbosacral Intervertebral Disc Degeneration

BACKGROUND

Unhealthy habits, such as overeating processed and high-calorie foods, alcohol abuse, and smoking, negatively impact human health. It has been suggested that the inflammatory process and the resulting growth of nerve fibers within the intervertebral disc (IVD) fissures is the main reason for the pain accompanying IVD degeneration (IVDD).

OBJECTIVES

The aim of this study was to determine whether smoking, alcohol consumption, overweight/obesity, or diabetes comorbidity contribute to the development of IVDD and how the aforementioned factors affect the levels of brain-derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF), and growth associated protein 43 (GAP-43) in the study and control groups (intervertebral discs, IVDs from cadavers, and serum samples from voluntary blood donors).

METHODS

The study group comprised 113 patients diagnosed with IVDD who qualified for microdiscectomy. Two control groups (I and II) were used in this study. The first included 81 IVDs obtained from Caucasian human cadavers. Control group II, on the other hand, included serum samples obtained from 113 voluntary blood donors. The expression profiles of BDNF, GDNF, and GAP-43 were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Our statistical analysis confirmed that patients who were overweight/obese, smoked tobacco, consumed alcohol, or had diabetes had a higher risk of IVDD (OR > 1). Statistical analysis showed that BDNF, GAP-43, and GDNF concentrations were significantly higher in the IVDs and serum samples obtained from the study group compared to the control group (p < 0.05). In addition, higher levels of BDNF, GDNF, and GAP-43 were noted in IVDD patients who consumed alcohol, smoked tobacco, were overweight/obese, or had comorbid diabetes compared to patients without these risk factors (p < 0.05).

CONCLUSION

We showed that changes in energy metabolism, habits, and lifestyle, as well as the degenerative process of IVD in the lumbosacral spine contribute to changing the concentration profile of the analyzed neurotrophic factors.

Risk factors for lumbar disc herniation recurrence after percutaneous endoscopic lumbar discectomy: a meta-analysis of 58 cohort studies

Recurrent lumbar disc herniation (rLDH) is one of the most serious complications and major causes of surgical failure and paralysis following percutaneous endoscopic lumbar discectomy (PELD). There are reports in the literature on the identification of risk factors associated with rLDH; however, the results are controversial. Therefore, we conducted a meta-analysis to identify risk factors for rLDH among patients following spinal surgery. PubMed, EMBASE, and the Cochrane Library were searched without language restrictions from inception to April 2018 for studies reporting risk factors for LDH recurrence after PELD. MOOSE guidelines were followed in this meta-analysis. We used a random effects model to aggregate odds ratios (ORs) with 95% confidence intervals (CIs). The evidence of observational studies was classified into high quality (class I), medium quality (class II/III), and low quality (class IV) based on the P value of the total sample size and heterogeneity between studies. Fifty-eight studies were identified with a mean follow-up of 38.8 months. Studies with high-quality (class I) evidence showed that postoperative LDH recurrence after PELD was significantly correlated with diabetes (OR, 1.64; 95% CI, 1.14 to 2.31), the protrusion type LDH (OR, 1.62; 95% CI, 1.02 to 2.61), and less experienced surgeons (OR, 1.54; 95% CI, 1.10 to 2.16). Studies with medium-quality (class II or III) evidence showed that postoperative LDH recurrence was significantly correlated with advanced age (OR, 1.11; 95% CI, 1.05 to 1.19), Modic changes (OR, 2.23; 95% CI, 1.53 to 2.29), smoking (OR, 1.31; 95% CI, 1.00 to 1.71), no college education (OR, 1.56; 95% CI, 1.05 to 2.31), obesity (BMI ≥ 25 kg/m²) (OR, 1.66; 95% CI, 1.11 to 2.47), and inappropriate manual labor (OR, 2.18; 95% CI, 1.33 to 3.59). Based on the current literature, eight patient-related and one surgery-related risk factor are predictors of postoperative LDH recurrence after PELD. These findings may help clinicians raise awareness of early intervention for patients at high risk of LDH recurrence after PELD.

Full-Endoscopic Lumbar Discectomy Approach Selection: A Systematic Review and Proposed Algorithm

STUDY DESIGN

A systematic review of the literature to develop an algorithm formulated by key opinion leaders.

OBJECTIVE

This study aimed to analyze currently available data and propose a decision-making algorithm for full-endoscopic lumbar discectomy for treating lumbar disc herniation (LDH) to help surgeons choose the most appropriate approach [transforaminal endoscopic lumbar discectomy (TELD) or interlaminar endoscopic lumbar discectomy (IELD)] for patients.

SUMMARY OF BACKGROUND DATA

Full-endoscopic discectomy has gained popularity in recent decades. To our knowledge, an algorithm for choosing the proper surgical approach has never been proposed.

MATERIALS AND METHODS

A systematic review of the literature using PubMed and MeSH terms was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Patient samples included patients with LDH treated with full-endoscopic discectomy. The inclusion criteria were interventional research (randomized and nonrandomized trials) and observation research (cohort, case-control, case series). Exclusion criteria were case series and technical reports. The criteria used for selecting patients were grouped and analyzed. Then, an algorithm was generated based on these findings with support and reconfirmation from key expert opinions. Data on overall complications were collected. Outcome measures included zone of herniation, level of herniation, and approach (TELD or IELD).

RESULTS

In total, 474 articles met the initial screening criteria. The detailed analysis identified the 80 best-matching articles; after applying the inclusion and exclusion criteria, 53 articles remained for this review.

CONCLUSIONS

The proposed algorithm suggests a TELD for LDH located in the foraminal or extraforaminal zones at upper and lower levels and for central and subarticular discs at the upper levels considering the anatomic foraminal features and the craniocaudal pathology location. An IELD is preferred for LDH in the central or subarticular zones at L4/L5 and L5/S1, especially if a high iliac crest or high-grade migration is found.

Case-matched radiological and clinical outcome evaluation of interlaminar versus microsurgical decompression of lumbar spinal stenosis

PURPOSE

Endoscopic spine surgery is a globally expanding technique advocated as less invasive for spinal stenosis treatment compared to the microsurgical approach. However, evidence on the efficiency of interlaminar full-endoscopic decompression (FED) vs. conventional microsurgical decompression (MSD) in patients with lumbar spinal stenosis is still scarce. We conducted a case-matched comparison for treatment success with consideration of clinical, laboratory, and radiologic predictors.

METHODS

We included 88 consecutive patients (FED: 36/88, 40.9%; MSD: 52/88, 59.1%) presenting with lumbar central spinal stenosis. Surgery-related (operation time, complications, length of stay (LOS), American Society of Anesthesiologists physical status (ASA) score, C-reactive protein (CRP), white blood cell count, side of approach (unilateral/bilateral), patient-related outcome measures (PROMs) (Oswestry disability index (ODI), numeric rating scale of pain (NRS; leg-, back pain), EuroQol questionnaire (eQ-5D), core outcome measures index (COMI)), and radiological (dural sack cross-sectional area, Schizas score (SC), left and right lateral recess heights, and facet angles, respectively) parameters were extracted at different time points up to 1-year follow-up. The relationship of PROMs was analyzed using Spearman's rank correlation. Surgery-related outcome parameters were correlated with patient-centered and radiological outcomes utilizing a regression model to determine predictors for propensity score matching.

RESULTS

Complication (most often residual sensorimotor deficits and restenosis due to hematoma) rates were higher in the FED (33.3%) than MSD (13.5%) group (p < 0.05), while all complications in the FED group were observed within the first 20 FED patients. Operation time was higher in the FED, whereas LOS was higher in the MSD group. Age, SC, CRP revealed significant associations with PROMs. We did not observe significant differences in the endoscopic vs. microsurgical group in PROMs. The correlation between ODI and COMI was significantly high, and both were inversely correlated with eQ-5D, whereas the correlations of these PROMs with NRS findings were less pronounced.

CONCLUSIONS

Endoscopic treatment of lumbar spinal stenosis was similarly successful as the conventional microsurgical approach. Although FED was associated with higher complication rates in our single-center study experience, the distribution of complications indicated surgical learning curves to be the main factor of these findings. Future long-term prospective studies considering the surgical learning curve are warranted for reliable comparisons of these techniques.

Use artificial neural network to recommend the lumbar spinal endoscopic surgical corridor

Objectives

The transforaminal and interlaminar approaches are the two main surgical corridors of full endoscopic lumbar surgery. However, there are no quantifying methods for assessing the best surgical approach for each patient. This study aimed to establish an artificial intelligence (AI) model using an artificial neural network (ANN).

Materials and Methods

Patients who underwent full endoscopic lumbar spinal surgery were enrolled in this research. Fourteen pre-operative factors were fed into the ANN. A three-layer deep neural network was constructed. Patient data were divided into the training, validation, and testing datasets.

Results

There were 899 patients enrolled. The accuracy of the training, validation, and test datasets were 87.3%, 85.5%, and 85.0%, respectively. The positive predictive values for the transforaminal and interlaminar approaches were 85.1% and 89.1%, respectively. The area under the curve of the receiver operating characteristic was 0.91. The SHapley Additive exPlanations algorithm was utilized to explain the relative importance of each factor. The surgical lumbar level was the most important factor, followed by herniated disc localization and migrating disc zone level.

Conclusion

ANN can effectively learn from the choice of an experienced spinal endoscopic surgeon and can accurately predict the appropriate surgical approach.

Risk Factors for Poor Outcomes Following Minimally Invasive Discectomy: A Post Hoc Subgroup Analysis of 2-Year Follow-up Prospective Data

Objective

A post hoc subgroup analysis of prospectively collected data from a randomized controlled trial was conducted to identify risk factors related to poor outcomes in patients who underwent minimally invasive discectomy.

Methods

Patients were divided into satisfied and dissatisfied subgroups based on Oswestry Disability Index (ODI), visual analogue scale (VAS) back pain score (VAS-back) and leg pain score (VAS-leg) at short-term and midterm follow-up according to the patient acceptable symptom state threshold. Demographic characteristics, radiographic parameters, and clinical outcomes between the satisfied and dissatisfied subgroups were compared using univariate and multivariate analysis.

Results

A total of 222 patients (92.1%) completed 2-year follow-up, and the postoperative ODI, VAS-back, and VAS-leg were significantly improved after surgery as compared to preoperatively. Multivariate analysis indicated older age (p=0.026), lateral recess stenosis (p=0.046), and lower baseline ODI (p=0.027) were related to poor short-term functional improvement. Higher baseline VAS-back (p=0.048) was associated with poor short-term relief of back pain, while absence of decreased sensation (p=0.019) and far-lateral disc herniation (p=0.004) were associated with poorer short-term relief of leg pain. Lumbar facet joint osteoarthritis was identified as a risk factor for poor functional improvement (p=0.003) and relief of back pain (p=0.031). Disc protrusion (p=0.036) predicted poorer relief of back pain at midterm follow-up.

Conclusion

In this study, several factors were identified to be predictive of poor surgical outcomes following minimally invasive discectomy. (ClinicalTrials.gov number: NCT01997086).

Full-Endoscopic Resection of a Recurrent Posterior Longitudinal Ligament Cyst: Technical Note

BACKGROUND

Posterior longitudinal ligament cysts are very rare lesions and do not usually recur. Microscopic resection is commonly performed. The aim of this article was to report a case of recurrent posterior longitudinal ligament cyst that benefited from full-endoscopic resection.

METHODS

We used the 25° endoscope of the RIWOspine set for interlaminar approach. A step-by-step description of the surgical technique was presented.

RESULTS

Clinical evolution was favorable. The patient remained pain-free 1 month after surgery, and postoperative magnetic resonance imaging showed complete resection of the cyst.

CONCLUSIONS

Endoscopy is a safe and feasible approach for posterior longitudinal ligament cysts, including unusual recurrent cases.