Disc height and segmental motion as risk factors for recurrent lumbar disc herniation

The Three-Step Approach for Lumbar Disk Herniation with Anatomical Insights Tailored for the Next Generation of Young Spine Surgeons

Background/Objectives: Lumbar disc herniation, a complex challenge in spinal health, significantly impacts individuals across diverse age groups. This article delves into the intricacies of this condition, emphasising the pivotal role of anatomical considerations in its understanding and management. Additionally, lumbar discectomy might be considered an "easy" surgery; nevertheless, it carries significant risks. The aim of the study was to present a groundbreaking "three-step approach" with some anatomical insight derived from our comprehensive clinical experiences, designed to systematise the surgical approach and optimise the outcomes, especially for young spine surgeons. We highlighted the purpose of the study and introduced our research question(s) and the context surrounding them. Methods: This retrospective study involved patients treated for lumbar disc herniation at a single institution. The patient demographics, surgical details, and postoperative assessments were meticulously recorded. All surgeries were performed by a consistent surgical team. Results: A total of 847 patients of the 998 patients initially included completed the follow-up period. A three-step approach was performed for every patient. The recurrence rate was 1.89%. Furthermore, the incidence of lumbar instability and the need for reoperation were carefully examined, presenting a holistic view of the outcomes. Conclusions: The three-step approach emerged as a robust and effective strategy for addressing lumbar disc herniation. This structured approach ensures a safe and educational experience for young spinal surgeons.

Development and validation of a nomogram to predict the risk of residual low back pain after tubular microdiskectomy of lumbar disk herniation

OBJECTIVE

Tubular microdiskectomy (tMD) is one of the most commonly used for treating lumbar disk herniation. However, there still patients still complain of persistent postoperative residual low back pain (rLBP) postoperatively. This study attempts to develop a nomogram to predict the risk of rLBP after tMD.

METHODS

The patients were divided into non-rLBP (LBP VAS score < 2) and rLBP (LBP VAS score ≥ 2) group. The correlation between rLBP and these factors were analyzed by multivariate logistic analysis. Then, a nomogram prediction model of rLBP was developed based on the risk factors screened by multivariate analysis. The samples in the model are randomly divided into training and validation sets in a 7:3 ratio. The Receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the diskrimination, calibration and clinical value of the model, respectively.

RESULTS

A total of 14.3% (47/329) of patients have persistent rLBP. The multivariate analysis suggests that higher preoperative LBP visual analog scale (VAS) score, lower facet orientation (FO), grade 2-3 facet joint degeneration (FJD) and moderate-severe multifidus fat atrophy (MFA) are risk factors for postoperative rLBP. In the training and validation sets, the ROC curves, calibration curves, and DCAs suggested the good diskrimination, predictive accuracy between the predicted probability and actual probability, and clinical value of the model, respectively.

CONCLUSION

This nomogram including preoperative LBP VAS score, FO, FJD and MFA can serve a promising prediction model, which will provide a reference for clinicians to predict the rLBP after tMD.

Optimizing prediction accuracy for early recurrent lumbar disc herniation with a directional mutation-guided SVM model

Percutaneous endoscopic lumbar discectomy (PELD) is one of the main means of minimally invasive spinal surgery, and is an effective means of treating lumbar disc herniation, but its early recurrence is still difficult to predict. With the development of machine learning technology, the auxiliary model based on the prediction of early recurrent lumbar disc herniation (rLDH) and the identification of causative risk factors have become urgent problems in current research. However, the screening ability of current models for key factors affecting the prediction of rLDH, as well as their predictive ability, needs to be improved. Therefore, this paper presents a classification model that utilizes wrapper feature selection, developed through the integration of an enhanced bat algorithm (BDGBA) and support vector machine (SVM). Among them, BDGBA increases the population diversity and improves the population quality by introducing directional mutation strategy and guidance-based strategy, which in turn allows the model to secure better subsets of features. Furthermore, SVM serves as the classifier for the wrapper feature selection method, with its classification prediction results acting as a fitness function for the feature subset. In the proposed prediction method, BDGBA is used as an optimizer for feature subset filtering and as an objective function for feature subset evaluation based on the classification results of the support vector machine, which improves the interpretability and prediction accuracy of the model. In order to verify the performance of the proposed method, this paper proves the performance of the model through global optimization experiments and prediction experiments on real data sets. The accuracy of the proposed rLDH prediction model is 93.49% and sensitivity is 88.33%. The experimental results show that Level of herniated disk, Modic change, Disk height, Disk length, and Disk width are the key factors for predicting rLDH, and the proposed method is an effective auxiliary diagnosis method.

Lumbar lordosis and sacral slope do not differ in two types of postoperative lumbar disc re-herniation: a cross-sectional observational study

BACKGROUND

To identify the differences of lumbar lordosis (LL) and sacral slope (SS) angles between two types of postoperative lumbar disc re-herniation, including the recurrence of same level and adjacent segment herniation (ASH).

METHODS

We searched the medical records of lumbar disc herniation (LDH) patients with re-herniation with complete imaging data (n = 58) from January 1, 2013 to December 30, 2020 in our hospital. After matching for age and sex, 58 patients with LDH without re-herniation from the same period operated by the same treatment group in our hospital were served as a control group. Re-herniation patients were divided into two groups, same-level recurrent lumbar disc herniation group (rLDHG) and adjacent segment herniation group with or without recurrence (ASHG). The preoperative, postoperative and one month after operation LL and SS were measured on standing radiographs and compared with the control group by using t-test, ANOVA, and rank-sum test. Next, we calculated the odds ratios (ORs) by unconditional logistic regression, progressively adjusted for other confounding factors.

RESULTS

Compared with the control group, the postoperative LL and SS were significantly lower in LDH patients with re-herniation. However, there were no differences in LL and SS between ASHG and rLDHG at any stage. After progressive adjustment for confounding factors, no matter what stage is, LL and SS remained unassociated with the two types of re-herniation.

CONCLUSIONS

Low postoperative LL and SS angles are associated with degeneration of the remaining disc. Low LL and SS may be independent risk factors for re-herniation but cannot determine type of recurrence (same or adjacent disc level).

Lumbar disc herniation: Prevention and treatment of recurrence: WFNS spine committee recommendations

Objective

This review aims to formulate the most current evidence-based recommendations on the epidemiology, prevention, and treatment of recurrent lumbar disc herniation (LDH).

Methods

We performed a systematic literature search in PubMed, Medline, and Google Scholar databases from 2012 to 2022 using the keywords "lumbar disc recurrence." Screening criteria resulted in 57 papers, which were summarized and presented at two international consensus meetings of the World Federation of Neurosurgical Societies (WFNS) Spine Committee. The 57 papers covered the following topics: (1) Definition and incidence of recurrence after lumbar disc surgery; (2) Prediction of recurrence before primary surgery; (3) Prevention of recurrence by surgical measures; (4) Prevention of recurrence by postoperative measures; (5) Treatment options for recurrent disc herniation; (6) The outcomes of recurrent disc herniation surgery. We utilized the Delphi method and voted on eight final consensus statements.

Results and conclusion

Recurrence after disc herniation surgery may be considered a surgical complication, its incidence is approximately 5% and is different from overall re-operation incidence. There are multiple risk factors predicting LDH recurrence, including smoking, younger age, male gender, obesity, diabetes, disc degeneration, and presence of lumbosacral transitional vertebrae. The level of lumbar discectomy surgery and the amount of disc material removed do not correlate with recurrence rate. Minimally invasive discectomies may have higher recurrence rates, especially during the surgeon's learning period. However, the experience of the surgeon is not related to recurrence. High-quality studies are needed to determine if activity restriction, weight loss, smoking cessation, and muscle-strengthening exercises after primary surgery can help prevent recurrence of LDH.The best treatment option for recurrent disc herniation is still being discussed. While complications of minimally invasive techniques may be lower than open discectomy, outcomes are similar. Fusion should only be considered when spinal instability and/or spinal deformity are present. Clinical outcomes and patient satisfaction after recurrent disc herniation surgery are inferior to those after initial discectomy.

The Importance of Spinopelvic Parameters in Recurrent Lumbar Disk Herniation

STUDY DESIGN

Retrospective clinical study.

OBJECTIVES

We aimed to investigate preoperative spinopelvic mismatch as a risk factor for recurrent lumbar disk herniation (RLDH) in patients undergoing lumbar disk herniation (LDH) surgery.

SUMMARY OF BACKGROUND DATA

Spinopelvic parameters have been associated with lumbar degenerative diseases, particularly LDH. However, the relationship between these parameters and RLDH has yet to be studied.

MATERIALS AND METHODS

Data of 1453 patients aged ≥18 who underwent single-level, unilateral fenestration microdiscectomy for the first time in our hospital between 2013 and 2019 were reviewed. The study group comprised 88 patients who underwent surgery for RLDH. The control group comprised 101 randomly selected patients who underwent surgery for LDH but not RLDH. Age, sex, body mass index, occupational activity level, operative level, Roussouly classification type, and time to recurrence were recorded. Moreover, pelvic incidence, lumbar lordosis (LL), interverteberal disk height (IDH), segmental lordosis, sacral slope (SS), pelvic tilt (PT), and sacral table angle (ST) were measured for each patient. Pelvic mismatch was calculated.

RESULTS

Mean age was 46.5±11.4 y (range, 20-70). Both groups were similar concerning age, sex, body mass index, occupational activity level, and level of surgery. The mean time to recurrence was 167.3±36.6 d (range, 62-363). Measurements in the RLDH group were as follows: IDH=7.6±1.5 mm, pelvic incidence =54.4°±10.1°, LL=47.3°±13°, segmental lordosis =9.3°±5°, SS=35.1°±9.9°, and PT=19.3°±7.3°. Mean IDH was significantly lower in the RLDH group ( P =0.02). Less LL and lower PT at L3-4 level and increased SS at L5-S1 level were considered risk factors for RLDH.

CONCLUSION

This study showed that preoperative low IDH is at higher risk for RLDH in patients undergoing LDH surgery. LL, PT, and SS may be risk factors for specific levels.

A Clinically Applicable Predictive Score in Lumbar Disc Disease for Formulating a Surgical Plan

STUDY DESIGN

Case control study.

OBJECTIVE

Micro-lumbar discectomy or Interbody fusion procedure are work-horse surgical procedures in management of lumbar disc disease. Spine surgeon in their early years of practice gets confused in choosing ideal surgical plan when dealing with a complex scenario. A clinical score is needed to guide spine surgeons in choosing an optimal surgical plan.

MATERIALS AND METHODS

Study was done with research grant approval from AO Spine. A predictive score was formulated as per hypothesis following a pilot study. Two fellowship trained spine surgeons-one using the score (Group A) and other not using score (Group B-control) treated 40 patients included in their respective group. All patients were analysed preoperatively, post-surgery at 12 months follow-up with Visual analog scale score for back pain, leg pain, Oswestry disability index score, SF-36 score. Change in parameters at 12 months follow-up were analysed statistically. P ≤ .05 was considered statistically significant. Success rate of individual surgeon who managed respective group of patients and Difficulty index of surgeon who managed without using score was evaluated at 12 months follow-up.

RESULTS

Success rate of Group A-surgeon was higher than Group B-surgeon .15% of Group B patients had poor surgical outcome at follow-up. Statistically significant improvement in Group A patients were seen in all 3 evaluated parameters when compared to Group B patients at 12 months of follow-up (P ≤ .05). Difficulty index of surgeon who didn't use the score was 15%.

CONCLUSION

The proposed predictive score comprising all risk factors, can be used by spine surgeons when they are confronted with difficult scenario in decision-making. Accuracy, reliability and validity of the score needs to be evaluated in a larger scale.

LEVEL OF EVIDENCE

Ⅲ.

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.

Radiologic Analysis of Causes of Early Recurrence After Percutaneous Endoscopic Transforaminal Discectomy

STUDY DESIGN

Retrospective study.

OBJECTIVE

To analyze the causes of and factors influencing early recurrence after TELD performed in the treatment of lumbar disc herniation.

METHODS

We included 285 patients with single-segment lumbar disc herniation treated using transforaminal endoscopy lumbar discectomy TELD from January 2017 to December 2019 at the First Affiliated Hospital of the University of South China. Patients were classified into early recurrence and non-early recurrence groups based on clinical symptoms and MRI reexamination. Imaging data (eg, disc height index (DHI), Pfirrman grades, base width, postoperative annulus-fibrosus tear size, cross-sectional area of the foramen (CSAF), etc.)were analyzed, and multivariate, binomial logistic regression was utilized to determine which factors were associated with early recurrence after TELD.

RESULTS

A total of 285 patients completed surgery and clinical follow-up, during which 19 patients relapsed within 6 months postsurgery, for an early recurrence rate of 6.7%. There were statistically significant differences between DHI, Pfirrman grades, base width, postoperative annulus-fibrosus tear size, herniation sites, CSAF and Modic changes between the early recurrence and non-early recurrence groups (P < .05). On multivariate logistic regression,the degree of disc degeneration (OR = .747, P = .037), CSAF (OR = 5.255, P = .006), degree of Modic change (OR = 1.831, P = .018) and base width of the herniation (OR = 4.942, P = .003) were significantly correlated with early recurrence after TELD.

CONCLUSIONS

Postoperative annulus-fibrosus tear size, DHI, and location of the disc herniation were associated with early recurrence after TELD. Increased base width of the herniation, severe disc degeneration, decreased CSAF and Modic change were risk factors for early recurrence after TELD.

Novel Modic grading scoring system and its clinical validation: a preliminary investigation

PURPOSE

To propose a novel Modic grading scoring system and explore the relationship between the Modic grading score and disc degeneration, disc herniation, disc height, and clinical symptom scores.

METHOD

In total, 194 patients were included in the study. The new Modic grading scoring system included four indicators: invaded vertebral height, invaded endplate length, endplate morphology, and grade of endplate defects. The severity of Modic changes was visually quantified by numerical scores, and the kappa value was used to verify the interobserver and intraobserver reliability. Spearman correlation analysis was used to explore the relationship between the Modic grading score and intervertebral disc degeneration, disc herniation, disc height, and clinical symptom scores.

RESULTS

The interobserver and intraobserver reliability showed substantial to almost perfect agreement in the new Modic grading scoring system. The Modic grading score was positively correlated with intervertebral disc degeneration (r = 0.757, p < 0.001) and negatively correlated with the intervertebral disc height index (r = - 0.231, p < 0.001). There was no significant correlation between the Modic grading scoring system and disc herniation (r = 0.369, p = 0.249). Additionally, there was no significant correlation between the Modic grading score and the Japanese Orthopaedic Association score (r = - 0.349, p = 0.25), Oswestry Disability Index score (r = 0.246, p = 0.11), or visual analogue scale score (r = 0.315, p = 0.35).

CONCLUSION

The new Modic grading scoring system had good interobserver and intraobserver reliability. The Modic grading score was positively correlated with intervertebral disc degeneration and negatively correlated with the intervertebral disc height.

Machine Learning Predicts Recurrent Lumbar Disc Herniation Following Percutaneous Endoscopic Lumbar Discectomy

STUDY DESIGN

Retrospective study.

OBJECTIVES

To develop machine learning (ML) models to predict recurrent lumbar disc herniation (rLDH) following percutaneous endoscopic lumbar discectomy (PELD).

METHODS

We retrospectively analyzed 1159 patients who had undergone single-level PELD for lumbar disc herniation (LDH) between July 2014 to December 2019 at our institution. Various preoperative imaging variables and demographic metrics were brought in analysis. Student's t test and Chi-squared test were applied for univariate analysis, which were feature selection for ML models. We established ML models to predict rLDH: Artificial neural networks (ANN), Extreme Gradient Boost classifier (XGBoost), KNeighborsClassifier (KNN), Decision tree classifier (Decision Tree), Random forest classifier (Random Forest), and support vector classifier (SVC).

RESULTS

A total 130 patients (11.22%) were diagnosed as rLDH in 1159 patients. Recurrence occurred within 10.25 ± 11.05 months. Body mass index (BMI) (P = .027), facet orientation (FO) (P < .001), herniation type (P = .012), Modic changes (P = .004), and disc calcification (P = .013) are significant factors in univariate analysis (P < .05). Extreme Gradient Boost classifier, Random Forest, ANN showed fine area under the curve, .9315, .9220, and .8814 respectively.

CONCLUSION

We developed a deep learning and 2 ensemble models with fine performance in prediction of rLDH following PELD. Predicting re-herniation before surgery has the potential to optimize decision-making and meaningfully decrease the rates of rLDH following PELD. Our ML model identified higher BMI, lower FO, Modic changes, disc calcification in a non-protrusive region, and herniation type (noncontained herniation) as significant features for predicting rLDH.

Analysis of risk factors for post-operative recurrence after percutaneous endoscopic lumbar discectomy in patients with lumbar disc herniation: a meta-analysis

BACKGROUND

This study aimed to systematically evaluate risk factors for post-operative recurrence after percutaneous endoscopic lumbar discectomy (PELD) in patients with lumbar disc herniation (LDH).

METHODS

The eligible studies were retrieved from PubMed, Embase, and Web of Science databases. Quality assessment was performed. The effects of binary variables (sex, Modic change (MC), type 2 diabetes (T2DM), and smoking) on post-operative recurrence were evaluated as odds ratio (OR) and 95% confidence interval (CI). The effects of continuous variables (sagittal range of motion (SROM), body mass index (BMI), and age) were assessed as weighted mean difference (WMD) and 95% CI. Sensitivity analysis and publication bias were conducted to evaluate the reliability of pooled results.

RESULTS

Eight studies were included, and their methodological quality was medium. MC (OR (95% CI) = 3.88 (2.24-6.74), P < 0.001), smoking (OR (95% CI) = 1.87 (1.45, 2.42), P < 0.001), T2DM (OR (95% CI) = 1.61 (1.12, 2.31), P = 0.010), SROM (WMD (95% CI) = 2.33 (0.95, 3.70), P = 0.001), BMI (WMD (95% CI) = 1.68 (1.37, 1.99) kg/m2, P < 0.001), and age (WMD (95% CI) = 9.95 (5.05, 14.86) years, P < 0.001) were significantly related to post-operative recurrence in patients with LDH after PELD. Significant publication bias was not observed among studies in all outcome indicators.

CONCLUSION

Our findings reveal that high levels of age, BMI, and SROM, history of T2DM or smoking, or more MC may be correlated with post-operative recurrence after PELD.

Interventional Therapy and Surgical Management of Lumbar Disc Herniation in Spine Surgery: A Narrative Review

Significant advancements in lumbar disc herniation (LDH) management have been made in interventional pain therapy, operative therapy, peri-operative management, and cost analysis of various procedures. The present review aims to provide a concise narrative of all these topics, current trends, and possible future directions in the management of LDH. Interventional pain management using intradiscal injections often serves as a minimally invasive non-surgical approach. Surgical modalities vary, including traditional open laminectomy, microdiscectomy, endoscopic discectomy, tubular discectomy, percutaneous laser disc decompression, and transforaminal foraminotomy. Prevention of infections during surgery is paramount and is often done via a single-dose preoperative antibiotic prophylaxis. Recurrence of LDH post-surgery is commonly observed and thus mitigative strategies for prevention have been proposed including the use of annular closure devices. Finally, all treatments are well-associated with clear as well as hidden costs to the health system and society as described by billing codes and loss of patients' quality-adjusted life-years. Our summary of recent literature regarding LDH may allow physicians to employ up-to-date evidence-based practice in clinical settings and can help drive future advancements in LDH management. Future longitudinal and comprehensive studies elucidating how each type of treatments fare against different types of herniations are warranted.

Minimally Invasive Transforaminal Interbody Fusion Versus Microdiscectomy Without Fusion for Recurrent Lumbar Disk Herniation: A Prospective Comparative Study

OBJECTIVE

The objective of this study was to compare the clinical outcome of minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) versus standard revision diskectomy for recurrent lumbar disk herniation (RLDH).

BACKGROUND

RLDH is the most common cause of redo surgery after a microdiscectomy. Commonly, in patients without evidence of spinal instability, many surgeons would simply redo microdiscectomy, while others proceed to a redo microdiscectomy with arthrodesis. According to the literature, there is no evidence of what the best management of an RLDH would be.

METHODS

This study involved 90 patients who underwent lumbar microdiscectomy in the past and were now experiencing a new lumbar disk herniation for the first time. The patients were divided into two groups, each with 45 patients: group A received standard revision microdiscectomy, whereas group B received revision microdiscectomy with MIS TLIF.The Japanese Orthopaedic Association score, operating time, blood loss, duration of hospital stay, costs, and complications were all prospectively recorded in a database and examined. Back and leg discomfort were measured using the visual analog scale.

RESULTS

The mean total postoperative Japanese Orthopaedic Association score across the groups exhibited no statistically significant difference, nor did the preoperative clinical and epidemiological data. Although postoperative leg pain was comparable in both groups, postoperative lower back pain in group A was much worse than that in group B. Additional revision surgery was necessary for six individuals in group A. Group A had higher rates of dural rupture and postoperative neurological impairment. Group A experienced much less intraoperative blood loss, longer operation times, and postoperative hospital stays.

CONCLUSION

In patients with RLDH, revision microdiscectomy is effective. In comparison with conventional microdiscectomy, MIS TLIF reduces intraoperative risk of dural rupture or neural injury, postoperative incidence of mechanical instability or recurrence, and postoperative lower back pain.

STUDY DESIGN

Prospective, randomized, multicenter, comparative study.

Risk Factors of Low Back Pain Aggravation After Tubular Microdiscectomy of Lumbar Disc Herniation

BACKGROUND

Although lumbar disc herniation (LDH) patients' sciatic symptoms such as leg pain can be improved by decompressive surgery, some patients report postoperative aggravated low back pain (LBP). However, the exact reason for this phenomenon remained unknown.

METHODS

We retrospectively analyzed the prospectively collected LDH data of patients who underwent tubular microdiscectomy between December 2015 and December 2020. The patients were divided into aggravated and non-aggravated group according to whether the postoperative LBP visual analogue scale (VAS) score was higher than the preoperative score. We analyzed the relationship of the clinical and radiologic parameters with aggravated LBP.

RESULTS

Postoperative aggravated LBP cases accounted for 14.1% (57 of 404) of this series. Of the 57 patients, 88% (50 of 57) had mild postoperative LBP aggravation (1-2), and 12% (7 of 57) had severe LBP aggravation (>2). The preoperative LBP VAS score of the aggravated group was significantly lower than that of the non-aggravated group (P < 0.001), while the LBP VAS score and Oswestry Disability Index at final follow-up was significantly higher in the aggravated group (P < 0.05). Additionally, the proportion of preoperative moderate-to-severe multifidus fatty atrophy (MFA) and lumbar facet joint degeneration (LFJD) was significantly higher in the aggravated group. A multiple stepwise logistic regression analysis indicated that the preoperative LBP VAS score (P < 0.001, odds ratio 0.266, 95% CI 0.161-0.439) and MFA (P < 0.001, odds ratio 4.491, 95% CI 2.092-9.640) were the risk factors for postoperative aggravated LBP.

CONCLUSIONS

A preoperative lower LBP VAS score and moderate-to-severe MFA were associated with postoperative aggravated LBP. This will provide important guidance for patient's preoperative assessment and education.

Recurrent Lumbar Disc Herniation: Does Transforaminal Lumbar Interbody Fusion Lead to Better Clinical and Radiological Outcomes than Redo-Discectomy?

STUDY DESIGN

randomized, prospective, and level I clinical study.

PURPOSE

To compare the clinical outcomes and radiological findings of revision discectomy alone versus revision discectomy with fusion as surgical treatment for recurrent lumbar disc herniation (RDH).

OVERVIEW OF LITERATURE

RDH is a common complication following a primary discectomy. The optimal surgical procedure for RDH is still debated.

METHODS

Sixty patients with RDH were randomly divided into two equal groups: the first group underwent revision discectomy alone and the second underwent revision discectomy with fusion. The primary outcomes evaluated were Visual Analog Scale (VAS) for low back and limb pains, Oswestry Disability Index (ODI), disc height indexes, foraminal height index, and disc height subsidence. Secondary outcomes included operative time, blood loss, postoperative hospital stay, and complications.

RESULTS

Revision discectomy with fusion showed superior pain relief and improved functional outcomes, including better VAS scores for both back and leg pain and ODI at 24-month follow-up. Additionally, it restored the stability of the spine better with lower disc height subsidence without significant complications. However, these advantages came at the cost of increased blood loss and longer operative time and hospital stays.

CONCLUSIONS

Revision discectomy with fusion is recommended for RDH; however, the choice of the procedure should be made caseby- case basis, considering many factors related to the patient and surgical facilities.

How to spot the recurring lumbar disc? Risk factors for recurrent lumbar disc herniation (rLDH) in adult patients with lumbar disc prolapse: a systematic review and meta-analysis

Despite a fast-growing evidence-base examining the relationship of certain clinical and radiological factors such as smoking, BMI and herniation-type with rLDH, there remains much debate around which factors are clinically important. We conducted a systematic review and meta-analysis to identify risk factors for recurrent lumbar disc herniation (rLDH) in adults after primary discectomy. A systematic literature search was carried out using Ovid-Medline, EMBASE, Cochrane library and Web of Science databases from inception to 23rd June-2022. Observational studies of adult patients with radiologically-confirmed rLDH after ≥3 months of the initial surgery were included, and their quality assessed using the Quality-In-Prognostic-Studies (QUIPS) appraisal tool. Meta-analyses of univariate and multivariate data and a sensitivity-analysis for rLDH post-microdiscectomy were performed. Twelve studies (n=4497, mean age:47.3; 34.5% female) were included, and 11 studies (n=4235) meta-analysed. The mean follow-up was 38.4 months. Mean recurrence rate was 13.1% and mean time-to-recurrence was 24.1 months (range: 6-90 months). Clinically, older age (OR:1.04, 95%CI:1.00-1.08, n=1014), diabetes mellitus (OR:3.82, 95%CI:1.58-9.26, n=2330) and smoking (OR:1.80, 95%CI:1.03- 3.14, n=3425) increased likelihood of recurrence. Radiologically, Modic-change type-2 (OR:7.93, 95%CI:5.70-11.05, n=1706) and disc extrusion (OR:12.23, 95%CI:8.60-17.38, n=1706) increased likelihood of recurrence. The evidence did not support an association between rLDH and sex; BMI; occupational labour/driving; alcohol-consumption; Pfirmann- grade, or herniation-level. Older patients, smokers, patients with diabetes, those with type-2 Modic-changes or disc extrusion are more likely to experience rLDH. Higher quality studies with robust adjustment of confounders are required to determine the clinical bearing of all other potential risk factors for rLDH.

Lumbar disc herniation in children and elderly patients

INTRODUCTION

Lumbar disc herniation is a common pathology of young and middle-aged patients. Fissures and tears in the annulus fibrosus become weak points that facilitate herniation of the nucleus pulposus, especially when extreme forces 'attack' the intervertebral disc. A significant biomechanical force applied to a healthy ('normal') disc can have the same effect. Disc protrusions and herniations to varying degrees penetrate the spinal canal.

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.

Moderate to Severe Multifidus Fatty Atrophy is the Risk Factor for Recurrence After Microdiscectomy of Lumbar Disc Herniation

OBJECTIVE

We attempted to investigate the potential risk factors of recurrent lumbar disc herniation (rLDH) after tubular microdiscectomy.

METHODS

We retrospectively analyzed the data of patients who underwent tubular microdiscectomy. The clinical and radiological factors were compared between the patients with and without rLDH.

RESULTS

This study included 350 patients with lumbar disc herniation (LDH) who underwent tubular microdiscectomy. The overall recurrence rate was 5.7% (20 of 350). The visual analogue scale (VAS) score and Oswestry Disability Index (ODI) at the final follow-up significantly improved compared with those preoperatively. There was no significant difference in the preoperative VAS score and ODI between the rLDH and non-rLDH groups, while the leg pain VAS score and ODI of the rLDH group were significantly higher than those of the non-rLDH group at final follow-up. This suggested that rLDH patients had a worse prognosis than non-rLDH patients even after reoperation. There were no significant differences in sex, age, body mass index, diabetes, current smoking and drinking, disc height index, sagittal range of motion, facet orientation, facet tropism, Pfirrmann grade, Modic changes, interdisc kyphosis, and large LDH between the 2 groups. Univariate logistic regression analysis revealed that rLDH was associated with hypertension, multilevel microdiscectomy, and moderate-severe multifidus fatty atrophy (MFA). A multivariate logistic regression analysis indicated that MFA was the sole and strongest risk factor for rLDH after tubular microdiscectomy.

CONCLUSION

Moderate-severe MFA was a risk factor for rLDH after tubular microdiscectomy, which can serve as an important reference for surgeons in formulating surgical strategies and the assessment of prognosis.

Machine Learning Prediction Model and Risk Factor Analysis of Reoperation in Recurrent Lumbar Disc Herniation Patients After Percutaneous Endoscopic Lumbar Discectomy

OBJECTIVE

To investigate the risk factors of reoperation after percutaneous endoscopic lumbar discectomy (PELD) due to recurrent lumbar disc herniation (rLDH) and to establish a set of individualized prediction models.

METHODS

Patients who underwent PELD successfully from January 2016 to February 2022 in a single institution were enrolled in this study. Six methods of machine learning (ML) were used to establish an individualized prediction model for reoperation in rLDH patients after PELD, and these models were compared with logistics regression model to select optimal model.

RESULTS

A total of 2603 patients were enrolled in this study. 57 patients had repeated operation due to rLDH and 114 patients were selected from the remaining 2546 nonrecurrent patients as matched controls. Multivariate logistic regression analysis showed that disc herniation type (P < .001), Modic changes (type II) (P = .003), sagittal range of motion (sROM) (P = .022), facet orientation (FO) (P = .028) and fat infiltration (FI) (P = .001) were independent risk factors for reoperation in rLDH patients after PELD. The XGBoost AUC was of 90.71%, accuracy was approximately 88.87%, sensitivity was 70.81%, specificity was 97.19%. The traditional logistic regression AUC was 77.4%, accuracy was about 77.73%, sensitivity was 47.15%, specificity was 92.12%.

CONCLUSION

This study showed that disc herniation type (extrusion, sequestration), Modic changes (type II), a large sROM, a large FO and high FI were independent risk factors for reoperation in LDH patients after PELD. The prediction efficiency of XGBoost model was higher than traditional Logistic regression analysis model.

Risk Factors for Recurrence After Percutaneous Endoscopic Lumbar Discectomy: A Meta-Analysis

OBJECTIVE

Postoperative recurrence of percutaneous endoscopic lumbar disc increases the physical damage and financial burden on patients and negatively affects physicians' treatment decisions. We conducted this meta-analysis to explore the risk factors for postoperative recurrence of percutaneous endoscopic lumbar disc for lumbar disc herniation.

METHODS

We conducted article search in the PubMed, EMBASE and Cochrane Library databases. PRISMA guidelines were followed in this review. The data are statistically analyzed by the Roundup Manager (version 3.6.1). The results of the meta-analysis are presented in the form of forest-like plots.

RESULTS

We included 13 articles and identified 7524 cases. Patients with older age (odds ratio [OR] = 1.28, 95% confidence interval [CI]: 1.18-1.40), higher body mass index (OR = 1.16, 95% CI: 1.05-1.28), smoker (OR = 1.73, 95% CI: 0.95-3.15), degenerative grades ≥3 (OR = 6.07, 95% CI: 2.81-13.11), and postoperative sagittal motion ≥10° (OR = 2.42, 95% CI: 1.63-3.58) have a higher recurrence rate.

CONCLUSIONS

A thorough preoperative evaluation is essential to prevent postoperative recurrence of percutaneous endoscopic lumbar discectomy. The study addresses several factors of preoperative evaluation, which is hopeful to provide a reference for neurosurgeons.

Development and Validation of a Nomogram to Predict the Risk of Lumbar Disk Reherniation within 2 Years After Percutaneous Endoscopic Lumbar Discectomy

OBJECTIVE

To develop and validate a nomogram for predicting recurrent lumbar disk herniation (LDH) within 2 years after percutaneous endoscopic lumbar discectomy.

METHODS

Information on patients' LDH was collected from 1 medical center between January 2015 and September 2020. The LASSO (least absolute shrinkage and selection operator) method was applied to select the most significant risk factors. A multivariate logistic regression analysis was used to develop a predictive model incorporating the possible factors selected by the LASSO regression model. The discriminant, corrected, and clinically useful prediction models were evaluated using consistency index (C-index), receiver operating characteristic curve, calibration curves, and decision curve analysis. Internal validation of clinical predictive power was also assessed by bootstrap validation.

RESULTS

A total of 690 patients with LDH were included in this study. Sixty-three patients experienced recurrence within 2 years whereas 627 experienced no recurrence. The nomogram predictors included age, body mass index, Modic change, Pfirrmann grade, and sagittal range of motion. The model had good discrimination power, with a reliable C-index of 0.868 (95% confidence interval, 0.822-0.913) and interval validation confirmed a higher C-index value of 0.846. The area under the receiver operating characteristic curve was 0.868, indicating a good predictive value. The decision curve analysis indicated that it was clinically feasible to use the predictive recurrence nomogram model.

CONCLUSIONS

We developed and validated a new accurate and effective nomogram for predicting recurrent LDH within 2 years after percutaneous endoscopic lumbar discectomy. Age, body mass index, Modic change, Pfirrmann grade, and sagittal range of motion were significant features for predicting rLDH.

Factors associated with incomplete clinical improvement in patients undergoing transforaminal endoscopic lumbar discectomy for lumbar disc herniation

PURPOSES

To analyze the clinical and radiographic risk factors that might predict incomplete clinical improvement after transforaminal endoscopic lumbar discectomy (TELD).

METHODS

A retrospective analysis was conducted from 194 consecutive patients who underwent TELD due to lumbar disc herniation (LDH). Patients with incomplete clinical improvement were defined from patient-reported outcomes of poor improvement in pain or disability after surgery and patient dissatisfaction. Clinical and radiographic characteristics were evaluated to identify predicting factors of poor outcomes.

RESULTS

Of 194 patients who underwent TELD procedures, 32 patients (16.5%) had incomplete clinical improvement and 12 patients (6.1%) required revision surgery. The mean ages were 46.4 years and most of the patients suffered from predominant leg pain (48.9%). The most common surgical level was L4-5 (63.9%). Overall, the Oswestry Disability Index (44.3-15), visual analog scores of back pain (4.9-1.8) and leg pain (7.3-1.6) were significantly improved after surgery. Multivariate logistic regression analysis demonstrated that high body mass index, history of previous surgery, preoperative disability, weakness, and disc degeneration were related to incomplete clinical improvement. There were 15 recurrent LDH (7.7%) with a total of 12 revision surgeries (6.2%).

CONCLUSIONS

We identified independent risk factors associated with incomplete clinical improvement following TELD, including overweight, significant preoperative disability or weakness and history of previous surgery. Advanced age, disc degeneration, vacuum phenomenon, and spondylolisthesis were also possible risk factors. Recognizing these risk factors would help decide whether patients are good candidates for TELD, and optimize the surgical planning preoperatively to achieve good surgical results.

Loss of lumbar disc height with age and its impact on pain and sensitivity associated behaviors in mice

PURPOSE

Aging is a risk factor for several debilitating conditions including those related to chronic back pain and intervertebral disc degeneration, both of which have no cure. Mouse models are useful tools for studying disc degeneration and chronic back pain in a tightly controlled and clinically relevant aging environment. Moreover, mice offer the advantage of carrying out longitudinal studies to understand the etiology and progression of disc pathology induced by genetic or surgical strategies. Previously, age-related behavioral trends of discomfort and enhanced nociception in mice were reported; however, whether these measures are mediated by structural and pathological changes in the disc is unknown.

METHODS

The goal of the present observational study was to identify behavioral correlates of age-related degenerative changes in the disc. Towards this, we collected radiographs from 150 mice (77 females) between three and 23 months of age and measured the disc height index for each level of lumbar disc. Behavioral measures were collected on several of these mice which included rearing and distance travelled in an open field test; time spent in rearing, reaching, immobile, and self-suspended in the tail suspension test; bilateral hind paw licking in response to cold allodynia using acetone; and unilateral hind paw licking in response to heat hyperalgesia using capsaicin.

RESULTS

Results show that the lower lumbar discs lose height with age and these changes are independent of body composition measures including body weight, bone mineral density, fat mass, lean weight mass, percent fat mass, and percent lean mass. Disc height positively correlates with rearing and mobility in the open field test, immobility in the tail suspension test, and thermal hyperalgesia. Disc height negatively correlates with cold allodynia and rearing in the tail suspension test. Furthermore, mediation analysis shows that the lumbosacral disc significantly mediates the effect of age on rearing in the open field test, but not cold allodynia, suggesting this behavior is a useful measure of age-related axial discomfort due to disc degeneration.

CONCLUSION

In summary, the findings from the current study show that disc height are associated with measures of axial discomfort and nociception in mice.

A clinical nomogram for predicting the residual low back pain after percutaneous endoscopic surgery for lumbar disc herniation

PURPOSE

Current findings suggest that minimally percutaneous endoscopic lumbar discectomy (PELD) is a practical therapeutic approach for lumbar disc herniation (LDH). However, some patients still end up with residual low back pain, even after surgery. Our study aims to construct and validate a nomogram to predict residual low back pain after PELD.

METHODS

The medical records of 355 LDH patients admitted to the author's hospital were retrospectively analyzed between January 2019 and December 2021. The patients were randomly divided into two groups with a ratio of 7:3, namely a modelling group and a validation group. The univariable logistics and multivariable regression methods were used to screen the independent risk factors. A nomogram was then drawn using independent risk factors selected from the univariable and multivariable regression analyses. The concordance index (C-index), the receiver operating characteristic (ROC) curve, the calibration curve, and the decision curve analysis were used to evaluate the nomogram's performance. Finally, the accuracy of the nomogram was verified by a validation cohort.

RESULTS

36.6% (130/355) of patients showed low back pain after percutaneous endoscopic lumbar discectomy, while 63.4% (225/355) showed no symptoms. Multivariable logistical regression analysis showed that Modic change (p < 0.05, OR = 1.813), fatty infiltration of the paravertebral muscle (p < 0.05, OR = 2.935), and edema of lumbodorsal fascia (p = 0.049, OR = 1.611) were significant risk factors for post-operative residual back pain. Moreover, the C-index of the predictive nomogram was 0.743 (0.681-0.805), the area under the receiver operating characteristic curve (AUC) value was 0.739, and the DCA results exhibit a net benefit between 0.16 and 0.66. The above internal validation methods demonstrate the nomogram's good predictive capability.

CONCLUSION

Each variable in the model had a quantitatively corresponding risk score, which can be used in predicting residual low back pain after PELD.

A novel classification based on magnetic resonance imaging for individualized surgical strategies of lumbar disc herniation

INTRODUCTION

Although the anatomy and pathology of lumbar disc herniation (LDH) have been clearly defined and classified in many studies, its imaging definition and classification still needs further clarification. This study intends to propose a novel classification and individualized surgical strategy for LDH based on preoperative magnetic resonance imaging (MRI).

MATERIALS AND METHODS

According to MRI features, LDH types were identified, and the corresponding surgical strategies were formulated to accurately remove the herniated discs while minimizing the disturbance to the normal disc. We retrospectively analyzed prospectively collected data of LDH patients who underwent surgery guided by this classification system.

RESULTS

This study included 357 patients with LDH who underwent tubular microdiscectomy. LDH was classified into four types based on MRI features. The inter- and intra-observer agreement using this classification was good. The follow-up results showed that surgery improved visual analog scale scores for low-back and leg pain and the Oswestry disability index in patients with different LDH types. The average recurrence rate at 1-5 years postoperatively was 5.62%. There was no significant difference in recurrence rates among the four LDH types (3.7-6.2%). MRI showed no significant differences in the Pfirrmann grade and disc height index of the operated segment between before surgery and 1-3 years after surgery. The operated segments did not show faster disc degeneration rates compared to adjacent proximal segments.

CONCLUSIONS

We proposed a novel classification system and an individualized surgical strategy for LDH based on preoperative MRI. Further, the surgical suitable interventions guided by this system achieved good clinical outcomes and mild recurrence rates.

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.

A 9-year retrospective cohort of patients with lumbar disc herniation: Comparison of patient characteristics and recurrence frequency by smoking status

To evaluate the association between smoking status and patient characteristics and to identify risk factors associated with recurrence in patients who underwent surgery for lumbar disc herniation (LDH). This retrospective study was carried out at Lokman Hekim University, Ankara, Turkey between January 1, 2021 and January 1, 2022. The medical data of patients who underwent microsurgical discectomy for LDH were retrospectively recorded. Patients with any reemergence of LDH within a 6-month period after surgery were defined as having recurrent LDH. A total of 1109 patients were included in the study and mean age was 50.7 ± 14.3 years. The frequency of hernia at L2-L3 and L3-L4 levels was higher in the nonsmoker group (P < .001). The frequency of cases with Pfirrmann Grade 4 degeneration was higher in the nonsmoker group than in smokers and ex-smokers (P < .001). Protrusion-type hernias were more common in nonsmokers (P = .014), whereas paracentral hernias were more common in smokers (P < .001). The overall frequency of recurrence was 20.4%, and was higher in smokers than in non-smokers and ex-smokers (P < .001). Multivariable logistic regression revealed that current smoking (OR: 2.778, 95% CI [confidence interval]: 1.939-3.980, P < .001), presence of Pfirrmann Grade 4&5 disc degeneration (OR: 4.217, 95% CI: 2.966-5.996, P < .001), and paracentral herniation (OR: 5.040, 95% CI: 2.266-11,207, P < .001) were associated with higher risk of recurrence, whereas presence of sequestrated disc was associated with lower risk of recurrence (OR: 2.262, 95% CI:0.272-0.717, P = .001). Taken together, our data show that smoking, increased degree of degeneration and paracentral hernia increase the risk of LDH recurrence, while sequestrated disc appears to decrease risk. Taking steps to combat smoking in individuals followed for LDH may reduce the risk of recurrence in LDH patients.

Risk Factors Involved in the Early and Medium-Term Poor Outcomes of Percutaneous Endoscopic Transforaminal Discectomy: A Single-Center Experience

Objective

To investigate the risk factors involved in the early and medium-term poor outcomes of percutaneous endoscopic transforaminal discectomy (PETD) treatment of lumbar disc herniation (LDH) at the L4-5 level.

Methods

Between January 2015 and May 2020, we recruited 148 LDH patients at the L4-5 level who underwent PETD surgery. The patients were divided into Groups A and B, according to the surgical outcomes. Good and excellent outcomes were categorized into Group A, and generally good and poor outcomes were categorized into Group B. Clinical parameters (age, gender, symptom duration, hospital stay, operation time, blood loss, straight-leg raising (SLR), visual analog scale (VAS), Oswestry Disability Index (ODI) score and modified MacNab criteria) and radiologic parameters (foraminal height (FH), intervertebral height index (IHI), intervertebral angle (IVA), sagittal range of motion (sROM), and lumbar lordosis (LL)) were collected and analyzed using univariate and multiple logistic regression analyses.

Results

At the 6-month follow-up post operation, univariate analysis revealed that the symptom duration, SLR, IHI, and sROM were strongly associated with poor outcomes. However, multiple logistic regression analysis demonstrated that prolonged symptom duration, large SLR angel, and large sROM were independent risk factors for poor outcomes. At the 2-year follow-up post operation, univariate analysis suggested that advanced age, prolonged symptom duration, large preoperative VAS score, small FH, small IHI, and large sROM were potential risk factors for poor outcomes. However, multiple logistic regression analysis demonstrated that prolonged symptom duration, small IHI, and large sROM were independent risk factors for poor outcomes.

Conclusion

Our study demonstrated that prolonged symptom duration, large SLR angel, and large sROM were independent risk factors for poor outcomes immediately following PETD at the L4-5 level. However, prolonged symptom duration, small IHI, and large sROM were independent risk factors for poor outcomes at medium-term post PETD at the L4-5 level.

Intraoperative Endplate Injury Following Transforaminal Lumbar Interbody Fusion

OBJECTIVE

To investigate the incidence, distribution characteristics, risk factors, and clinical outcomes of intraoperative endplate injury following transforaminal lumbar interbody fusion (TLIF).

METHODS

Patients who underwent single-level TLIF from January 2018 to December 2020 were included. The patients were separated into endplate injury group (EI group) and no endplate injury group (non-EI group) by postoperative computed tomography scanning immediately. All patients' demographic, clinical, and radiographic parameters were analysed. Clinical outcomes were evaluated by visual analogue scale (VAS) for low back pain and Oswestry Disability Index (ODI).

RESULTS

576 patients were enrolled in this study. The rates of endplate injury were 19.6% (113 of 576) of patients and 9.9% (114 of 1152) of endplates. The rate of superior endplate injury was significantly higher than that of inferior endplate injury. The results illustrated that older age, lower disc height index (DHI), and taller cage height were independent risk factors for intraoperative endplate injury. The postoperative drain output, total blood loss, postoperative duration of drainage tube, and postoperative hospital stay in EI group were significantly more than those in non-EI group. There were no statistical differences in ODI and VAS scores at the same time point between two groups.

CONCLUSIONS

The rates of endplate injury were 19.6% of patients and 9.9% of endplates. The superior endplates are more susceptible to injury than inferior endplates. Older age, lower DHI, and taller cage height were independent risk factors for intraoperative endplate injury. Clinical outcomes were not affected by intraoperative endplate injury during early postoperative follow-up.

Radiographic evaluation of lumbar intervertebral disc height index: An intra and inter-rater agreement and reliability study

PURPOSE

To evaluate intra- and inter-rater agreement and reliability of seven reported disc height index (DHI) measurement methods on standing lateral X-ray of lumbar spine.

METHODS

The adult patients who had standing lateral X-ray of lumbar spine were recruited. Seven methods were used to measure DHI of each lumbar intervertebral disc level, including a ratio of sum of anterior and posterior disc height (DH) to disc diameter (Method 1), a ratio of middle DH to mid-vertebral body height (Method 2), a ratio of middle DH to disc diameter (Method 3), a ratio of the mean of anterior, middle, and posterior DH to the sagittal diameter of the proximal vertebral body (Method 4), a ratio of DH to vertebral height which cross the centre of adjacent vertebral bodies (Method 5), a ratio of the mean of anterior, middle, and posterior DH to the mean of proximal and distal vertebral body height (Method 6), and a ratio of the sum of anterior and posterior DH to the sum of superior and inferior disc depth (Method 7). Two raters conducted the measurements (one medical student (SS) and the other an experienced spine surgeon (XC)). Bland and Altmańs Limits of Agreement (LOA) with standard difference were calculated to examine intra- and inter-rater agreements between two out of seven methods for DHI. Intra-class correlations (ICC) with 95% confidence intervals were calculated to assess intra- and inter-rater reliability.

RESULTS

The intra-rater reliability in DHI measurements for 288 participants were ICCs from 0.807 (0.794, 0.812) to 0.922 (0.913, 0.946) by rater 1 (SS) and from 0.827 (0.802, 0.841) to 0.918 (0.806, 0.823) by rater 2 (XC). Method 2, 3, and 5 on all segmental levels had bias (95 % CI does not include zero) or/and out of the acceptable cut-off proportion (>50 %). A total of 609 outliers in 9174 segmental levels' LOA range. Inter-rater reliability was good-to-excellent in all but method 2 (0.736 (0.712, 0.759)) and method 5 (0.634 (0.598, 0.667)). ICCs of related lines to good-to-excellent reliability methods was excellent in all but only indirect lines in method 1 and 4 (ICCs lie in the range from 0.8 to 0.9).

CONCLUSION

Following a structured protocol, intra- and inter-rater reliability was good-to-excellent for most DHI measurement methods on X-ray. However, the complicated methods (more indirect lines) and IVD degeneration (nucleus pulposus degeneration and disc herniation) potentially affected the agreement on inter-rater measurements. Method 7 is the best reproducible method to measure disc height index for all intervertebral disc segmental levels with a good-to-excellent intra- and inter-rater reliability and agreement.

Psoas muscle measurement as a predictor of recurrent lumbar disc herniation: A retrospective blind study

AbstractParaspinal (erector spinae and multifidus) and psoas muscles contribute to spinal stability, but no study has yet examined the relationship between muscle mass and recurrent lumbar disc herniation (rLDH). The purpose of this study was to investigate the effect of psoas and paraspinal muscle mass on recurrent Lumbar disc herniation (LDH). This retrospective study included 49 patients with LDH (22 men, 27 women; mean age: 59.9 years; range 32-80) who underwent discectomy and partial laminectomy without fusion and underwent both pre- and postoperative magnetic resonance imaging. The presence of rLDH was determined using medical records and postoperative magnetic resonance imagings. Patients were divided into an rLDH group (26 patients) and a without-rLDH group (23 patients). Clinical characteristics, segmental motion, and paraspinal and psoas muscle mass were compared between the groups. Using ImageJ software, the cross-sectional area (CSA), lean muscle mass (LMM), and skeletal muscle index (SMI) were measured on T2 axial preoperative magnetic resonance images at L2-L3, L3-L4, and L4-L5 disc levels to represent muscle mass. Univariate and multivariate logistic regression analyses were performed. In the rLDH group, patients were younger (52.6 years vs 68.2 years; P = .001), segmental instability was more common (50.0% vs 4.3%; P = .001), and the CSA, LMM, CSASMI, and LMMSMI of psoas muscles were larger (5851.59 mm2 vs 4264.93 mm2, 5456.59 mm2 vs 4044.77 mm2, 18.77 cm2/m2 vs 13.86 cm2/m2, and 17.52 cm2/m2 vs 12.98 cm2/m2; P < .01 for all 4 variables). On multivariate logistic regression, age and segmental instability were independent risk factors for rLDH (odds ratio 0.886 and 18.527; P = .01 and P = .02, respectively). In middle-aged and elderly patients with lumbar disc herniation, relatively younger age, segmental instability, and greater psoas muscle mass may be risk factors for recurrence.

ISSLS Prize in Bioengineering Science 2022: low rate cyclic loading as a therapeutic strategy for intervertebral disc regeneration

BACKGROUND

The intervertebral disc degenerates with age and has a poor propensity for regeneration. Small molecule transport plays a key role in long-term degradation and repair. Convection (bulk flow), induced by low rate cyclic loading of the intervertebral disc, has been shown to increase transport of small molecules. However, the potential therapeutic benefit of low rate cyclic loading on degenerated discs has not been described. The purpose of this study was to determine if a sustained (daily) low rate cyclic loading regimen could slow, arrest, or reverse intervertebral disc degeneration in the rabbit lumbar spine.

METHODS

Fifty-six New Zealand white rabbits (>12 months old) were designated as either Control (no disc puncture), 8D (disc puncture followed by 8 weeks of degeneration), 16D (disc puncture followed by 16 weeks of degeneration), or Therapy (disc puncture followed by 8 weeks of degeneration and then 8 weeks of daily low rate cyclic loading). Specimens were evaluated by T2 mapping, Pfirrmann scale grading, nucleus volume, disc height index, disc morphology and structure, and proteoglycan content.

RESULTS

In every metric, mean values for the Therapy group fell between Controls and 8D animals. These results suggest that sustained low rate cyclic loading had a therapeutic effect on the already degenerated disc and the regimen promoted signs of regeneration. If these results translate clinically, this approach could fulfil a significant clinical need by providing a means of non-invasively treating intervertebral disc degeneration.

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

Many risk factors associated with recurrent lumbar disk herniation (RLDH) following lumbar discectomy (LD) have been reported. This study aimed to elucidate the biomechanical-radiological, clinical, and demographic factors that affect symptomatic RLDH prospectively.We collected prospective data of 988 consecutive patients with LDH who underwent LD at our department from January 2014 to December 2015. Patients who met the study criteria and were followed up postoperatively for more than 5 years were included (n = 816). Patients were divided into 3 groups; group 1 included patients who experienced symptomatic RLDH within the first postoperative 24 months (PO24M), group 2 included patients with symptomatic RLDH after PO24M, and group 3 included the patients who hadn't experienced symptomatic RLDH/LDH. The preoperative biomechanical-radiological, clinical, and the patients' demographic characteristics were compared among the groups.A total of 816 patients with 842 LDH met our study criteria. The mean age at the first LD was 46.9 years. The mean follow-up period was 72.8 months. The preoperative trauma history, postoperative trauma history, and BMI > 24.5 kg/m² were independent risk factors for RLDH. Large sROM at the L4-5 level and a higher intervertebral disk height index (IDH) were significantly higher in groups 1 and 2.Biomechanical-radiological and demographic factors can affect the incidence of symptomatic RLDH. To reduce the risk of RLDH, patients with these risk factors should receive more attention during surgical interventions. The patients should avoid gaining weight and potential traumatic accidents.

Application of Wearable Sensors Technology for Lumbar Spine Kinematic Measurements during Daily Activities following Microdiscectomy Due to Severe Sciatica

Simple Summary

The recurrence rate after lumbar spine disc surgeries is estimated to be 5–15%. Lumbar spine flexion of more than 10° is mentioned in the literature as the most harmful load to the operated disc level that could lead to recurrence during the first six postoperative weeks. The purpose of this study is to quantify flexions during daily living following such surgeries, for six weeks postoperatively, using wearable sensors technology. These data determine the patients’ kinematic pattern, reflecting a high-risk factor for pathology recurrence. The operated patients were measured to have 30% normal lumbar motion after the first postoperative week, while they were restored to almost 75% at the end of the sixth, respectively. Further in vitro studies should be carried out using these data to identify if such kinematic patterns could lead to pathology recurrence.

Abstract

Background: The recurrence rate of lumbar spine microdiscectomies (rLSMs) is estimated to be 5–15%. Lumbar spine flexion (LSF) of more than 10° is mentioned as the most harmful load to the intervertebral disc that could lead to recurrence during the first six postoperative weeks. The purpose of this study is to quantify LSFs, following LSM, at the period of six weeks postoperatively. Methods: LSFs were recorded during the daily activities of 69 subjects for 24 h twice per week, using Inertial Measurement Units (IMU). Results: The mean number of more than 10 degrees of LSFs per hour were: 41.3/h during the 1st postoperative week (P.W.) (29.9% healthy subjects-H.S.), 2nd P.W. 60.1/h (43.5% H.S.), 3rd P.W. 74.2/h (53.7% H.S.), 4th P.W. 82.9/h (60% H.S.), 5th P.W. 97.3/h (70.4% H.S.) and 6th P.W. 105.5/h (76.4% H.S.). Conclusions: LSFs constitute important risk factors for rLDH. Our study records the lumbar spine kinematic pattern of such patients for the first time during their daily activities. Patients’ data report less sagittal plane movements than healthy subjects. In vitro studies should be carried out, replicating our results to identify if such a kinematic pattern could cause rLDH. Furthermore, IMU biofeedback capabilities could protect patients from such harmful movements.

Overweight and smoking promote recurrent lumbar disk herniation after discectomy

PURPOSE

Recurrent lumbar disk herniation (rLDH) following lumbar microdiscectomy is common. While several risk factors for primary LDH have been described, risk factors for rLDH have only sparsely been investigated. We evaluate the effect of Body mass index (BMI) and smoking on the incidence and timing of rLDH.

METHODS

From a prospective registry, we identified all patients undergoing primary tubular microdiscectomy (tMD), with complete BMI and smoking data, and a minimum 12-month follow-up. We defined rLDH as reherniation at the same level and side requiring surgery. Overweight was defined as BMI > 25, and obesity as BMI > 30. Intergroup comparisons and age- and gender-adjusted multivariable regression were carried out. We conducted a survival analysis to assess the influence of BMI and smoking on time to reoperation.

RESULTS

Of 3012 patients, 166 (5.5%) underwent re-microdiscectomy for rLDH. Smokers were reoperated more frequently (6.4% vs. 4.0%, p = 0.007). Similarly, rLDH was more frequent in obese (7.5%) and overweight (5.9%) than in normal-weight patients (3.3%, p = 0.017). Overweight smokers had the highest rLDH rate (7.6%). This effect of smoking (Odds ratio: 1.63, 96% CI: 1.12-2.36, p = 0.010) and BMI (Odds ratio: 1.09, 95% CI: 1.02-1.17, p = 0.010) persisted after controlling for age and gender. Survival analysis demonstrated that rLDH did not occur earlier in overweight patients and/or smokers.

CONCLUSIONS

BMI and smoking may directly contribute to a higher risk of rLDH, but do not accelerate rLDH development. Smoking cessation and weight loss in overweight or obese patients ought to be recommended with discectomy to reduce the risk for rLDH.

Risk Factors and Surgical Management of Recurrent Herniation after Full-Endoscopic Lumbar Discectomy Using Interlaminar Approach

Full-endoscopic lumbar discectomy (FED) is one of the least invasive procedures for lumbar disc herniation. Patients who receive FED for lumbar disc herniation may develop recurrent herniation at a frequency similar to conventional procedures. Reoperation and risk factors of recurrent lumbar disc herniation were investigated among 909 patients who received FED using an interlaminar approach (FED-IL). Sixty-five of the 909 patients received reoperation for recurrent herniation. Disc height, smoking, diabetes mellitus (DM), subligamentous extrusion (SE) type, and Modic change were identified as the risk factors for recurrence. Other indicators such as LL, Cobb angle, disc migration, age, sex, and body mass index (BMI) did not reach significance. Among 65 patients, reoperation was performed within 14 days following FED-IL (very early) in 7 patients, from 15 days to 3 months (early) in 14 patients, from 3 months to 1 year (midterm) in 17 patients, and after more than 1 year (late) in 27 patients. The very early group included a greater number of males, and the mean age was significantly lower in comparison to other groups. All patients in the very early group received FED-IL for reoperation. Reoperation within 2 weeks allows FED-IL to be performed without adhesion. Fusion surgery was performed on three cases in the early and midterm groups and on 10 cases in the late group, which increased over time as degenerative change and adhesion progressed. The procedure selected to treat recurrent herniation mostly depends on the surgeon’s preference. Revision FED-IL is the first choice for recurrent herniation in terms of minimizing surgical burden, whereas fusion surgery offers the advantage that discectomy can be performed through unscarred tissues. FED-IL is recommended for recurrent herniation within 2 weeks before adhesion progresses.

RISK FACTORS FOR RECURRENT LUMBAR DISK HERNIATION

ABSTRACT Objective: to investigate the frequency of recurrent lumbar disk herniation (rLDH) and evaluated risk factors of rLDH in Russian population. Methods: this was a retrospective clinical study. From January 2015 to March 2022, 218 patients having single-level LDH at three institutes were included in this clinical study and who were then observed for a minimum of 5 years postoperatively. All the patients or relatives gave informed consent to participate in this study. The levels of disk herniation were L4-L5 in 132 cases (60.5 %), and L5-S1 in 86 cases (39.4 %). Results: The rLDH group was composed of 31 male and 12 female, whose ages ranged from 18 to 57 years (34.8±9.5 years). The non-rLDH group was composed of 97 male and 78 female, whose ages ranged from 19 to 73 years (47.5±9.8 years). According to the constructed binary logistic model, body mass index (p=0.021), current smoking (p=0.017), stage of disk degeneration (p=0.043), facet tropism (p=0.037), disk height index (p=0.018) and apparent diffusion coefficient (p=0.009) are significantly associated with incidence of rLDH. Conclusions: patients with these risk factors should be paid more attention for prevention of rLDH. Level of Evidence III; Retrospective Study.

Effectiveness of an Annular Closure Device to Prevent Recurrent Lumbar Disc Herniation: A Secondary Analysis With 5 Years of Follow-up

IMPORTANCE

Patients with large annular defects following lumbar microdiscectomy for disc herniation are at increased risk for symptomatic recurrence and reoperation.

OBJECTIVE

To determine whether a bone-anchored annular closure device in addition to lumbar microdiscectomy resulted in lower reherniation and reoperation rates vs lumbar microdiscectomy alone.

DESIGN, SETTING, AND PARTICIPANTS

This secondary analysis of a multicenter randomized clinical trial reports 5-year follow-up for enrolled patients between December 2010 and October 2014 at 21 clinical sites. Patients in this study had a large annular defect (6-10 mm width) following lumbar microdiscectomy for treatment of lumbar disc herniation. Statistical analysis was performed from November to December 2020.

INTERVENTIONS

Lumbar microdiscectomy with additional bone-anchored annular closure device (device group) or lumbar microdiscectomy only (control group).

MAIN OUTCOMES AND MEASURES

The incidence of symptomatic reherniation, reoperation, and adverse events as well as changes in leg pain, Oswestry Disability Index, and health-related quality of life when comparing the device and control groups over 5 years of follow-up.

RESULTS

Among 554 randomized participants (mean [SD] age: 43 [11] years; 327 [59%] were men), 550 were included in the modified intent-to-treat efficacy population (device group: n = 272; 270 [99%] were White); control group: n = 278; 273 [98%] were White) and 550 were included in the as-treated safety population (device group: n = 267; control group: n = 283). The risk of symptomatic reherniation (18.8% [SE, 2.5%] vs 31.6% [SE, 2.9%]; P < .001) and reoperation (16.0% [SE, 2.3%] vs 22.6% [SE, 2.6%]; P = .03) was lower in the device group. There were 53 reoperations in 40 patients in the device group and 82 reoperations in 58 patients in the control group. Scores for leg pain severity, Oswestry Disability Index, and health-related quality of life significantly improved over 5 years of follow-up with no clinically relevant differences between groups. The frequency of serious adverse events was comparable between the treatment groups. Serious adverse events associated with the device or procedure were less frequent in the device group (12.0% vs 20.5%; difference, -8.5%; 95% CI, -14.6% to -2.3%; P = .008).

CONCLUSIONS AND RELEVANCE

In patients who are at high risk of recurrent herniation following lumbar microdiscectomy owing to a large defect in the annulus fibrosus, this study's findings suggest that annular closure with a bone-anchored implant lowers the risk of symptomatic recurrence and reoperation over 5 years of follow-up.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01283438.

Adjuvant surgical decision-making system for lumbar intervertebral disc herniation after percutaneous endoscopic lumber discectomy: a retrospective nonlinear multiple logistic regression prediction model based on a large sample

BACKGROUND CONTEXT

Lumbar disc herniation (LDH) is a common condition that can affects an individual' quality of life. In patients for whom conservative treatment is ineffective after 3 months, surgical treatment, such as percutaneous endoscopic lumbar discectomy (PELD), is recommended. Because PELD is minimally invasive and produces thorough nerve root decompression, both surgeons and patients often prefer it to other techniques.

PURPOSE

Surgeons find it challenging to prevent postoperative recurrent LDH (rLDH) when they use PELD. We created and verified a model for evaluating patients' recurrence risk factors before surgery so that surgeons can choose other surgical techniques when necessary.

STUDY DESIGN

Retrospective study.

PATIENT SAMPLE

One thousand eight hundred seven patients who underwent PELD at our hospital between 2012 and 2015 were enrolled.

OUTCOME MEASURE

The main outcome measure was rLDH at any follow-up time point.

METHODS

Data were retrospectively analyzed for 1807 patients who underwent PELD at our hospital at some point between 2012 and 2015; all patients had been monitored for at least 5 years after surgery. They were divided into a recurrence group and a nonrecurrence group. Clinical and radiological risk factors were assessed over time to determine their correlations with recurrence and to exclude less important factors. A nonlinear multivariate logistic regression model was established to predict the recurrence rate before surgery.

RESULTS

A total of 1706 patients were monitored after PELD; data were missing for 101 additional patients. The total recurrence rate was 10.38%, and the most common time from surgery to recurrence was 1 year. Ten risk factors were assessed and included in the analysis. Regarding clinical risk factors, patients with hypertension (p < .001; correlation coefficient R [R] = 0.235; odds ratio [OR] = 4.749), diabetes (p < .001; R = 0.381; OR = 16.797), a history of smoking (p < .001; R = 0.347; OR = 9.012), and a history of performing intense physical labor (p < .001; R = 0.409; OR = 19.592) had a higher recurrence rate. Regarding radiological risk factors, patients with disc degeneration (Pfirrmann grade III) (p < .001; R = 0.228; OR = 4.919), Modic changes (level 2) (p < .001; R = 0.309; OR = 7.934), herniation in the form of extrusion (p < .001; R = 0.365; OR = 12.228), a higher disc height index (DHI) (p < .001; R = 0.336), and a larger segmental range of motion (p < .001; R = 0.243) had a higher recurrence rate. When the lumbar motion angle was negative (p < .001; R = 0.318; OR = 13.680), the recurrence rate was high. The overall accuracy of the final model was 97.6% (1665 of 1706). The recognition rate for non-rLDH cases was 99.0% (1514 of 1529), and the rate for rLDH cases was 85.3% (151 of 177); the AUC was 0.9315. A simple model was used. For those patients with postoperative trauma (p < .001; R = 0.382; OR = 13.680), a comparison model was established, and the corresponding recurrence rate was 23.0% ± 25.0% (0-76%).

CONCLUSIONS

A large cohort of patients underwent long-term monitoring, and 11 risk factors were verified for assessing each patient's risks before surgery to predict the postoperative recurrence of LDH following PELD. The risk of recurrence may be effectively reduced with the use of alternative surgical techniques in high risk cases.

Lumbar Stabilization with DSS-HPS® System: Radiological Outcomes and Correlation with Adjacent Segment Degeneration

Arthrodesis has always been considered the main treatment of degenerative lumbar disease. Adjacent segment degeneration is one of the major topics related to fusion surgery. Non-fusion surgery may prevent this because of the protective effect of persisting segmental motion. The aims of the study were (1) to describe the radiological outcomes in the adjacent vertebral segment after lumbar stabilization with DSS-HPS^® system and (2) to verify the hypothesis that this system prevents the degeneration of the adjacent segment. This is a retrospective monocentric analysis of twenty-seven patients affected by degenerative lumbar disease underwent spinal hybrid stabilization with the DSS-HPS^® system between January 2016 and January 2019. All patients completed 1-year radiological follow-up. Preoperative X-rays and magnetic resonance images, as well as postoperative radiographs at 1, 6 and 12 months, were evaluated by one single observer. Pre- and post-operative anterior and posterior disc height at the dynamic (DL) and adjacent level (AL) were measured; segmental angle (SA) of the dynamized level were measured. There was a statistically significant decrease of both anterior (p = 0.0003 for the DL, p = 0.036 for the AL) and posterior disc height (p = 0.00000 for the DL, p = 0.00032 for the AL); there were a statistically significant variations of the segmental angle (p = 0.00000). Eleven cases (40.7%) of radiological progression of disc degeneration were found. The DSS-HPS^® system does not seem to reduce progression of lumbar disc degeneration in a radiologic evaluation, both in the dynamized and adjacent level.

Nomograms for Predicting Recurrent Herniation in PETD with Preoperative Radiological Factors

Purpose

To investigate the preoperative radiological risk factors for recurrent lumbar disc herniation (rLDH) within 1 year after percutaneous endoscopic transforaminal discectomy (PETD).

Patients and Methods

A retrospective case–control study was conducted. Between January 2013 and November 2019, a total of 1210 patients with single-level L4/5 LDH who underwent PETD were enrolled in the present study. In total, 62 rLDH patients were diagnosed and collected based on the clinical and radiological manifestations, and 224 non-rLDH controls were selected from the remaining 1148 patients. Preoperative radiological parameters were collected and measured. An age threshold to distinguish patients into subgroups was established using the Youden index. The relationships between the risk factors and rLDH were evaluated by univariate and multivariate analyses in two subgroups. Predictive models were established based on logistic analysis. The area under the curve (AUC) of receiver operating characteristic (ROC) curves, calibration plots, and decision curve analysis (DCA) were used to assess the predictive models.

Results

In the present study, logistic analysis identified six significant predictors associated with rLDH in the young group: superior endplate concave angle (ECA), sacral slope, Modic changes, sagittal range of motion (sROM), extension intervertebral angle (IVA), and lumbar lordosis. Four significant predictors were identified in the elderly group: disc height index (DHI), retrolisthesis (posterior spondylolisthesis), sROM, and extension IVA. Validation of both models demonstrated excellent model discrimination (AUC= 0.940 and 0.946, respectively). DCA also showed excellent clinical utility and benefits.

Conclusion

The nomograms that we constructed could accurately predict individual patient recurrence risk. Individualized measures should be taken for patients of different ages with the above risk factors, and tailored postoperative surveillance of patients who underwent PETD can be planned.

The association between pain scores and disc height change following discectomy surgery in lumbar disc herniation patients: a systematic review and meta-analysis

PURPOSE

To evaluate the impact of discectomy on disc height (DH) in lumbar disc herniation (LDH) patients following discectomy surgery and address the association of DH change with pain score change.

METHODS

We searched three online databases for randomized controlled trials (RCTs) and observational studies. In LDH patients, eligible for discectomy surgery, the changes in pre- and post-operative back and/or leg pain score and DH and/or disc height index (DHI) were considered as primary outcomes. Standardize mean difference (SMD) and their 95% confidence intervals (CI) were evaluated. The GRADE approach was used to summarize the strength of evidence.

RESULTS

Two RCTs and sixteen observational studies were included in the analysis of 893 LDH patients undergoing discectomy surgery. The mean overall follow-up was 211 weeks. There was a statistically significant reduction in DH (14.4% reduction: SMD =  -0.74 (95% CI =  -0.86 to -0.61)) and DHI (11.5% reduction: SMD =  -0.81 (95% CI =  -0.97 to -0.65)) following discectomy surgery. There was a significant relationship between the reduction in DH and decrease in back pain score (r = 0.68, (95% CI = 0.07-1.30), p = 0.034) after discectomy surgery. No significant relationship between DHI change and decrease in clinical pain scores (back and leg pain) could be established.

CONCLUSION

Discectomy surgery produces significant and quantifiable reductions in DH and DHI. Additionally, the reduction in DH is responsible for the decrease in back pain scores post discectomy, but further studies will improve understanding and aid preoperative counselling.

Fusion versus nonfusion treatment for recurrent lumbar disc herniation

Background:

Recurrent lumbar disc herniation (RLDH) is one of the major causes for failure of primary surgery. The optimal surgical treatment of RLDH remains controversial.

Aim:

Retrospectively, we evaluate 135 patients and compare the clinical outcomes between fusion and nonfusion treatment of RLDH.

Methods:

Records of 75 men and 35 women aged 28–60 years for conventional revision discectomy alone (nonfusion) and 15 men and 10 women aged 30–65 years for revision discectomy with transforaminal lumbar interbody fusion (TLIF) and transpedicular screw fixation (fusion) were reviewed. Demographics, surgical data, and complications were collected and pre- and postoperative assessment were done by the Visual Analogue Scale (VAS) scale and Japanese Orthopaedic Association (JOA) score. The results after surgery were assessed according to the recovery rate as excellent, good, fair, and poor.

Results:

The mean follow-up period was 28.8 and 24.6 months in Group A (nonfusion) and Group B (fusion group), respectively. The preoperative data between both the groups showed no statistically significant difference. The postoperative mean VAS and JAO scores, recovery rate, and satisfaction rate showed no statistically significant difference except postoperative low back pain and occasional radicular pain and neurological deficit in nonfusion group which was significantly higher than that of fusion group. In comparison to fusion group, nonfusion group required significantly less operative time, less intraoperative blood loss, less postoperative hospital stay, no blood transfusion, and less total cost of the procedure. Satisfaction rate was 80% and 88% in nonfusion and fusion groups, respectively.

Conclusions:

Both convention revision discectomy (nonfusion) and discectomy with instrumented fusion (TLIF) surgery are effective in patients with RLDH.

Regulation of the inflammatory cycle by a controllable release hydrogel for eliminating postoperative inflammation after discectomy

Surgery is the final choice for most patients with intervertebral disc degeneration (IDD). Operation-caused trauma will cause inflammation in the intervertebral disc. Serious inflammation will cause tissue defects and induce tissue degeneration, IDD recurrence and the occurrence of other diseases. Therefore, we proposed a scheme to treat recurrence after discectomy by inhibiting inflammation with an aspirin (ASP)-loaded hydrogel to restore the mechanical stability of the spine and relieve local inflammation. ASP-liposomes (ASP-Lips) were incorporated into a photocrosslinkable gelatin-methacryloyl (GelMA) via mixing. This material can effectively alleviate inflammation by inhibiting the release of high mobility group box 1 (HMGB1) from the nucleus to the cytoplasm. We further assessed the expression of inflammatory cytokines, such as interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α), and degeneration-related factors, such as type II collagen (COL-2), Aggrecan, matrix metallopeptidases-3 (MMP-3), MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4) and ADAMTS-5 in rat nucleus pulpous cells. The level of IDD was analyzed through H&E, safranin-O staining and immunohistochemistry in rabbit samples. In vitro, we found that ASP-Lip@GelMA treatment significantly decreased inflammatory cytokines, MMP-3 and -13, and ADAMTS-4 and -5 and up-regulated COL-2 and Aggrecan via the inhibited release of HMGB-1 from the nucleus. In vivo, ASP-Lip@GelMA can effectively inhibit inflammation of local tissue after disc surgery and fill local tissue defects. This composite hydrogel system is a promising way to treat the recurrence of IDD after surgery without persistent complications.

Radiological risk factors for recurrent lumbar disc herniation after percutaneous transforaminal endoscopic discectomy: a retrospective matched case-control study

PURPOSE

To investigate radiological risk factors for recurrent lumbar disc herniation (rLDH) after percutaneous transforaminal endoscopic discectomy (PTED).

METHODS

Patients who underwent PTED due to a single-level L4-L5 or L5-S1 disc herniation from January 2013 to May 2019 were enrolled in this study. A matched case-control design was carried out in a single institution. Cases were defined as those who developed rLDH, and controls were matched from those patients without rLDH according to corresponding clinical characteristics. The radiological parameters were compared between two groups. The radiological risk factors for rLDH after PTED were identified by univariate and multivariate logistic regression analysis.

RESULTS

A total of 2186 patients who underwent PTED at L4-L5 or L5-S1 level were enrolled in this study. Sixty-eight patients were diagnosed with rLDH, and 136 patients were selected from the remaining 2118 nonrecurrent patients as matched controls. Univariate analysis demonstrated that herniation type (P = 0.009), surgical-level disc degeneration (P < 0.001), adjacent-level disc degeneration (P = 0.017), disc height index (DHI) (P = 0.003), and sagittal range of motion (sROM) (P < 0.001) were significantly related to rLDH. Multiple logistic regression analysis showed that low grade of surgical-level disc degeneration (P < 0.001), senior grade of adjacent-level disc degeneration (P < 0.001), a high DHI (P = 0.012), and a large sROM (P < 0.001) were the radiological independent risk factors.

CONCLUSION

This study showed that low grade of surgical-level disc degeneration, senior grade of adjacent-level disc degeneration, a high DHI, and a large sROM were the radiological independent risk factors for rLDH after PTED.

Risk factors for early reherniation after lumbar discectomy with or without annular closure: results of a multicenter randomized controlled study

BACKGROUND

Reherniation after lumbar discectomy is classified as a failure and occurs in 3 to 18% of cases. Various risk factors for reherniation such as age, sex, body mass index, smoking, and size of annular defect have been reported. The aim of this study was to identify risk factors for early reherniation after one-level lumbar discectomy with or without annular closure within 3 months after surgery.

METHODS

This study is based on data analysis of a prospective, multicenter randomized controlled trial in Europe. Patients included underwent standard lumbar discectomy-with or without implantation of an annular closure device (ACD). Enrollment of 554 patients in 21 centers in Europe (Germany, Switzerland, Austria, Belgium, The Netherlands, and France) started in 2010 and was completed in October 2014. A total of 276 patients were randomized to the ACD group (ACG) and 278 patients to the control group (CG).

RESULTS

Four (1.5%) symptomatic reherniations occurred in the ACG and 18 (6.5%) in the CG. In the overall population, a significant correlation was found with recurrent herniation for disc degeneration (Pfirrmann p = 0.009) and a trend for current smoker status (p = 0.07). In CG, age ≥ 50 years (p = 0.05) and disc degeneration (Pfirrmann p = 0.026, Kellgren and Lawrence p = 0.013) were predictive factors for reherniation.

CONCLUSION

In the current study, risk factors for early recurrent disc herniation after lumbar discectomy were age ≥ 50 years and moderate disc degeneration. The annular closure device reduced the risk of early reherniation.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01283438.