Preoperative estimation of disc herniation recurrence after microdiscectomy: predictive value of a multivariate model based on radiographic parameters

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).

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.

Management of recurrent lumbar disc herniation: a comparative analysis of posterior lumbar interbody fusion and repeat discectomy

Background

For recurrent lumbar disc herniation, many experts suggest a repeat discectomy without stabilization due to its minimal tissue manipulation, lower blood loss, shorter hospital stay, and lower cost, recent research on the role of instability in disc herniation has made fusion techniques popular among spinal surgeons. The authors compare the postoperative outcomes of posterior lumbar interbody fusion (PLIF) and repeat discectomy for same-level recurrent disc herniation.

Methods

The patients included had previously undergone discectomy and presented with a same-level recurrent lumbar disc herniation. The patients were placed into two groups: 1) discectomy only, 2) PLIF based on the absence or presence of segmental instability. Preoperative and postoperative Oswestry disability index scores, duration of surgery, blood loss, duration of hospitalization, and complications were analyzed.

Results

The repeat discectomy and fusion groups had 40 and 34 patients, respectively. The patients were followed up for 2.68 (1-4) years. There was no difference in the duration of hospitalization (3.73 vs. 3.29 days P=0.581) and operative time (101.25 vs. 108.82 mins, P=0.48). Repeat discectomy had lower intraoperative blood loss, 88.75 ml (50-150) versus 111.47 ml (30-250) in PLIF (P=0.289). PLIF had better ODI pain score 4.21 (0-10) versus 9.27 (0-20) (P-value of 0.018). Recurrence was 22.5% in repeat discectomy versus 0 in PLIF.

Conclusion

PLIF and repeat discectomy for recurrent lumbar disc herniation have comparable intraoperative blood loss, duration of surgery, and hospital stay. PLIF is associated with lower durotomy rates and better long-term pain control than discectomy. This is due to recurrence and progression of degenerative process in discectomy patients, which are eliminated and slowed, respectively, by PLIF.

Advancing insights into recurrent lumbar disc herniation: A comparative analysis of surgical approaches and a new classification

Background

The management of recurrent lumbar disc herniation (rLDH) lacks a consensus. Consequently, the choice between repeat microdiscectomy (MD) without fusion, discectomy with fusion, or endoscopic discectomy without fusion typically hinges on the surgeon's expertise. This study conducts a comparative analysis of postoperative outcomes among these three techniques and proposes a straightforward classification system for rLDH aimed at optimizing management.

Patients and Methods

We examined the patients treated for rLDH at our institution. Based on the presence of facet resection, Modic-2 changes, and segmental instability, they patients were categorized into three groups: Types I, II, and III rLDH managed by repeat MD without fusion, MD with transforaminal lumbar interbody fusion (TLIF) (MD + TLIF), and transforaminal endoscopic discectomy (TFED), respectively.

Results

A total of 127 patients were included: 52 underwent MD + TLIF, 50 underwent MD alone, and 25 underwent TFED. Recurrence rates were 20%, 12%, and 0% for MD alone, TFED, and MD + TLIF, respectively. A facetectomy exceeding 75% correlated with an 84.6% recurrence risk, while segmental instability correlated with a 100% recurrence rate. Modic-2 changes were identified in 86.7% and 100% of patients experiencing recurrence following MD and TFED, respectively. TFED exhibited the lowest risk of durotomy (4%), the shortest operative time (70.80 ± 16.5), the least blood loss (33.60 ± 8.1), and the most favorable Visual Analog Scale score, and Oswestry Disability Index quality of life assessment at 2 years. No statistically significant differences were observed in these parameters between MD alone and MD + TLIF. Based on this analysis, a novel classification system for recurrent disc herniation was proposed.

Conclusion

In young patients without segmental instability, prior facetectomy, and Modic-2 changes, TFED was available should take precedence over repeat MD alone. However, for patients with segmental instability, MD + TLIF is recommended. The suggested classification system has the potential to enhance patient selection and overall outcomes.

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.

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.

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.

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.

Development, validation, and visualization of a web-based nomogram to predict the effect of tubular microdiscectomy for lumbar disc herniation

Objective

The purpose of this study was to retrospectively collect the relevant clinical data of lumbar disc herniation (LDH) patients treated with the tubular microdiscectomy (TMD) technique, and to develop and validate a prediction model for predicting the treatment improvement rate of TMD in LDH patients at 1 year after surgery.

Methods

Relevant clinical data of LDH patients treated with the TMD technology were retrospectively collected. The follow-up period was 1 year after surgery. A total of 43 possible predictors were included, and the treatment improvement rate of the Japanese Orthopedic Association (JOA) score of the lumbar spine at 1 year after TMD was used as an outcome measure. The least absolute shrinkage and selection operator (LASSO) method was used to screen out the most important predictors affecting the outcome indicators. In addition, logistic regression was used to construct the model, and a nomogram of the prediction model was drawn.

Results

A total of 273 patients with LDH were included in this study. Age, occupational factors, osteoporosis, Pfirrmann classification of intervertebral disc degeneration, and preoperative Oswestry Disability Index (ODI) were screened out from the 43 possible predictors based on LASSO regression. A total of 5 predictors were included while drawing a nomogram of the model. The area under the ROC curve (AUC) value of the model was 0.795.

Conclusions

In this study, we successfully developed a good clinical prediction model that can predict the effect of TMD for LDH. A web calculator was designed on the basis of the model (https://fabinlin.shinyapps.io/DynNomapp/).

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.

A scoping review of complication prediction models in spinal surgery: An analysis of model development, validation and impact

Background

Predictive analytics are being used increasingly in the field of spinal surgery with the development of models to predict post-surgical complications. Predictive models should be valid, generalizable, and clinically useful. The purpose of this review was to identify existing post-surgical complication prediction models for spinal surgery and to determine if these models are being adequately investigated with internal/external validation, model updating and model impact studies.

Methods

This was a scoping review of studies pertaining to models for the prediction of post-surgical complication after spinal surgery published over 10 years (2010-2020). Qualitative data was extracted from the studies to include study classification, adherence to Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidelines and risk of bias (ROB) assessment using the Prediction model study Risk Of Bias Assessment Tool (PROBAST). Model evaluation was determined using area under the curve (AUC) when available. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement was used as a basis for the search methodology in four different databases.

Results

Thirty studies were included in the scoping review and 80% (24/30) included model development with or without internal validation. Twenty percent (6/30) were exclusively external validation studies and only one study included an impact analysis in addition to model development and internal validation. Two studies referenced the TRIPOD guidelines and there was a high ROB in 100% of the studies using the PROBAST tool.

Conclusions

The majority of post-surgical complication prediction models in spinal surgery have not undergone standardized model development and internal validation or adequate external validation and impact evaluation. As such there is uncertainty as to their validity, generalizability, and clinical utility. Future efforts should be made to use existing tools to ensure standardization in development and rigorous evaluation of prediction models in spinal surgery.

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.

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.

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.

Artificial intelligence predicts disk re-herniation following lumbar microdiscectomy: development of the "RAD" risk profile

PURPOSE

Surgical treatment of herniated lumbar intervertebral disks is a common procedure worldwide. However, recurrent herniated nucleus pulposus (re-HNP) may develop, complicating outcomes and patient management. The purpose of this study was to utilize machine-learning (ML) analytics to predict lumbar re-HNP, whereby a personalized risk prediction can be developed as a clinical tool.

METHODS

A retrospective, single center study was conducted of 2630 consecutive patients that underwent lumbar microdiscectomy (mean follow-up: 22-months). Various preoperative patient pain/disability/functional profiles, imaging parameters, and anthropomorphic/demographic metrics were noted. An Extreme Gradient Boost (XGBoost) classifier was implemented to develop a predictive model identifying patients at risk for re-HNP. The model was exported to a web application software for clinical utility.

RESULTS

There were 1608 males and 1022 females, 114 of whom experienced re-HNP. Primary herniations were central (65.8%), paracentral (17.6%), and far lateral (17.1%). The XGBoost algorithm identified multiple re-HNP predictors and was incorporated into an open-access web application software, identifying patients at low or high risk for re-HNP. Preoperative VAS leg, disability, alignment parameters, elevated body mass index, symptom duration, and age were the strongest predictors.

CONCLUSIONS

Our predictive modeling via an ML approach of our large-scale cohort is the first study, to our knowledge, that has identified significant risk factors for the development of re-HNP after initial lumbar decompression. We developed the re-herniation after decompression (RAD) profile index that has been translated into an online screening tool to identify low-high risk patients for re-HNP. Additional validation is needed for potential global implementation.

MRI predictors of revision surgery after primary lumbar discectomy

The prognostic significance of preoperative MRI findings in patients undergoing discectomy is incompletely understood. Identifying the radiological predictors of revision surgery on pre-operative MRI can guide management decisions and potentially prevent multiple surgeries. We included 181 patients who underwent primary lumbar discectomy between 2010 and 2014. All patients were contacted via a short telephone interview to determine if they had revision surgery within 5 years of their index surgery. Preoperative MRI of the lumbosacral spine was evaluated for various radiological factors including type of disc herniation, anatomical location of herniation, direction of herniation, degree of disc degeneration, end plate changes and presence of listhesis. Other potential confounders including age, gender, smoking status and index level of surgery were also recorded. Multivariate model of all radiological predictors and confounders were developed and a step-wise approach was used to remove insignificant variables in order to develop final significant multivariate model. P value of <0.05 was considered statistically significant. Patients with retrolisthesis were found to be 2.7 times more likely than the patients without listhesis to require revision surgery (p = 0.019). Patients with foraminal disc herniation were 3.45 times more likely than the patients with paramedian disc herniation to require revision surgery (p = 0.026). Other MRI predictors failed to achieve statistical significance. Based on the data presented patients with retrolisthesis and/or foraminal disc herniation should be counselled on the relatively higher risk of revision surgery when proceeding with discectomy, or alternative options should be considered.

Evaluation of Predictive Models for Complications following Spinal Surgery

BACKGROUND

 Complications rates vary across spinal surgery procedures and are difficult to predict due to heterogeneity in patient characteristics, surgical methods, and hospital volume. Incorporation of predictive models for complications may guide surgeon decision making and improve outcomes.

METHODS

 We evaluate current independently validated predictive models for complications in spinal surgery with respect to study design and model generation, accuracy, reliability, and utility. We conducted our search using Preferred Reporting Items for Systematic Review and Meta-analysis guidelines and the Participants, Intervention, Comparison, Outcomes, Study Design model through the PubMed and Ovid Medline databases.

RESULTS

 A total of 18 articles met inclusion criteria including 30 validated predictive models of complications after adult spinal surgery. National registry databases were used in 12 studies. Validation cohorts were used in seven studies for verification; three studies used other methods including random sample bootstrapping techniques or cross-validation. Reported area under the curve (AUC) values ranged from 0.37 to 1.0. Studies described treatment for deformity, degenerative conditions, inclusive spinal surgery (neoplasm, trauma, infection, deformity, degenerative), and miscellaneous (disk herniation, spinal epidural abscess). The most commonly cited risk factors for complications included in predictive models included age, body mass index, diabetes, sex, and smoking. Those models in the deformity subset that included radiographic and anatomical grading features reported higher AUC values than those that included patient demographics or medical comorbidities alone.

CONCLUSIONS

 We identified a cohort of 30 validated predictive models of complications following spinal surgery for degenerative conditions, deformity, infection, and trauma. Accurate evidence-based predictive models may enhance shared decision making, improve rehabilitation, reduce adverse events, and inform best practices.

Predictors of Treatment Success Following Limited Discectomy With Annular Closure for Lumbar Disc Herniation

Background

Previous studies have demonstrated bone-anchored annular closure to significantly reduce reherniation and reoperation rates after lumbar discectomy in patients with large annular defects. It is important to identify the prognostic factors that may be associated with successful treatment. This study aimed to identify predictors of treatment success in patients with lumbar disc herniation treated with limited microdiscectomy supplemented by a bone-anchored annular closure device (ACD).

Methods

This study was a retrospective analysis of 133 consecutive patients with lumbar disc herniation treated with the ACD. Treatment success was defined as ≥24% improvement in visual analog scale (VAS) for back pain, ≥39% improvement in VAS leg pain, and ≥33% in the Oswestry Disability Index (ODI), with the raw ODI score ≤48. Success was calculated at 3, 6, and 12 months after surgery. Potentially predictive outcomes included patient characteristics, operative data, and imaging outcomes, such as disc, facet, and end plate morphology. Logistic regression was used to determine the significant predictive factors for treatment success.

Results

After 3, 6, and 12 months, 97 of 131 (74%), 104 of 129 (81%), and 112 of 126 (89%) patients, respectively, achieved the success criteria. At 3 months follow-up, a higher proportion of younger (17-40 years) versus older (41-65 years) patients met the success criteria (P = .025). On the basis of logistic regression, the following factors were significantly associated with treatment success at 1 or more of the follow-up time points: sex (male), lower body mass index, higher baseline pain and ODI scores, lower grade preoperative disc degeneration, and the absence of a postoperative complication. The rates of index-level recurrent herniation and reoperation were 1.5% and 3.0%, respectively.

Conclusions

This real-world evidence supports a promising benefit-risk profile for augmenting limited microdiscectomy with a bone-anchored ACD and provides some insights into the patient populations that may have a greater chance of realizing significant improvements in pain and function.

Level of Evidence

2 (Cohort study).

Predictors of satisfaction after lumbar disc herniation surgery in elderly

Background

The aim of this study was to evaluate satisfaction and factors associated with satisfaction in elderly undergoing lumbar disc herniation surgery.

Methods

In the national Swedish register for spinal surgery (SweSpine) we identified 2095 patients aged > 65 years (WHO definition of elderly) whom during 2000–2016 had undergone LDH surgery and had pre- and one-year postoperative data (age, gender, preoperative duration and degree of back- and leg pain, quality of life (SF-36) and one-year satisfaction (dissatisfied, uncertain, satisfied). We utilized a logistic regression model to examine preoperative factors that were independently associated with low and high satisfaction and after LDH surgery.

Results

One year after surgery, 71% of the patients were satisfied, 18% uncertain and 11% dissatisfied. Patients who were satisfied were in comparison to others, younger, had shorter preoperative duration of leg pain, higher SF-36 mental component summary and more leg than back pain (all p < 0.01). Patients who were dissatisfied were compared to others older, had longer preoperative duration of leg pain and lower SF-36 scores (all p < 0.01). 81% of patients with leg pain up to 3 months were satisfied in comparison with 57% of patients with leg pain > 2 years (p < 0.001).

Conclusion

Only one out of ten elderly, is dissatisfied with the outcome of LDH surgery. Age, preoperative duration of leg pain, preoperative SF 36 score, and for satisfaction also dominance of back over leg pain, are in elderly factors associated to good and poor subjective outcome after LDH surgery.

APOPTOSIS, NUTRITION, AND METABOLISM OF TRANSPLANTED INTERVERTEBRAL DISC CELLS

ABSTRACT Introduction: Apoptosis is a contributing factor to degenerating intervertebral disc (IVD). Disc regeneration has been attempted by transplanting cells into the disc, with some gains in disc height achieved in animal models. Here, we study whether the apoptotic microenvironment affects the transplanted disc cells. Methods: Human annulus fibrosus (AF) and nucleus pulposus (NP) cells were grown in media then starved for 5 days in vitro by not changing the media. Three aspects of apoptotic cell influence on the transplanted cells were tested in a total of 32 samples: 1) the effect of apoptotic cytokines in the media, 2) reduced glucose in the media, and 3) apoptotic cell bodies in the flask. The Trypan Blue, AlamarBlue®, and 1,9-Dimethyl-Methylene Blue assays for sulfated glycosaminoglycan (sGAG) content were performed (n=4). Results: There were significant decreases in cell viability between the control, 25% conditioned media (CM) and starved control group. There were no significant differences in cell number, metabolic activity or sGAG production in cells grown in different conditioned media compared to cells grown in complete media. The cells of the control decreased in viability and number over the 5 days without feeding, then improved dramatically when feeding was resumed. Flasks that received transplanted cells in addition to renewed feeding did not recover as much as the cells in the re-fed group. Conclusions: Cytokines from starved cells negatively impact on the viability of healthy cells. Starving cells that receive new sources of nutrition have even higher viability than transplanted cells. This indicates that altering and improving the nutrient supply problem in the IVD could be a valuable option. Level of Evidence III; Case control studyg.

OUTCOMES OF SURGICAL TREATMENT OF LUMBAR DISK HERNIATION USING AN ANNULAR CLOSURE DEVICE

ABSTRACT Objective: The aim of the study was to investigate the clinical and radiological results of using the annular closure device in patients with lumbar disc herniation (LDH). Methods: The study involved 120 patients with LDH operated on by limited discectomy and annular closure using the Barricaid device. A literature review was conducted to evaluate the effectiveness of the annuloplasty. Results: All patients showed postoperative regression of the radicular pain syndrome and were mobilized on the day of surgery. The correlation between the removed nucleus pulposus and changes in DHI was studied by linear regression. The results revealed that disc height loss is directly correlated with the volume of removed nucleus pulposus (p <0.05). Modic changes were present in 22 (22%) patients. Endplate changes (resorption and erosion) were present in 25 patients (20.7%). We found that these changes in MR and CT images have no effect on the clinical presentation of the disease. No intraoperative complications, such as severe hemorrhage requiring blood transfusion, or injury to the dura mater or nerve roots, were observed in our case series. Postoperative complications occurred in 3 (2.5%) patients. The reoperation rate was 4.2%. Conclusions: The use of the Barricaid annular closure device in 120 patients with lumbar disc herniation and high risk of recurrent herniation showed good clinical and radiographic outcomes. The reoperation rate in our study was 2.5%; disc reherniation at the operated level was observed in 1.7% of patients. This is a good outcome compared to the data reported for patients having a high risk of disc reherniation. Level of Evidence IV; Case series.

ANALYSIS OF POSTOPERATIVE OUTCOMES OF DEGENERATIVE DISEASES OF THE LUMBOSACRAL JUNCTION

ABSTRACT Objective: The article presents an analysis of the clinical efficacy and causes of unsatisfactory outcomes of surgical treatment in patients with degenerative diseases of the lumbosacral junction of the spine. Methods: Patients were allocated to one of three groups, depending on the method of surgical intervention on the lumbosacral junction: 1) (n=352) - operated by the method of microsurgical discectomy; 2) (n=83) - operated with the use of artificial IVD prostheses; 3) (n = 183) - operated with the use of interbody fusion and posterior rigid stabilization. To investigate the causes of unsatisfactory outcomes, a correlation analysis was conducted of long-term clinical outcomes with preoperative instrumental parameters in the operated segment, surgical tactics used, and the development of complications. Results: It is determined that long-term “good” clinical outcomes are associated with individual preoperative parameters of the lumbosacral junction of the spine - linear displacement, sagittal angulation, height of the interbody space, degree of IVD degeneration by ADC. Conclusion: In degenerative diseases of the lumbosacral junction of the spine, the detailed analysis of long-term clinical outcomes enable the identification of the causes that affect the development of unsatisfactory outcomes, which are individual morphostructural changes in the lower lumbar segment: the amplitude of the segmental angle, the angle of the lumbar lordosis, the degree of linear displacement of the vertebrae, the height of the interbody space, and ADC. Complex clinical and instrumental analysis enabled us to determine possible surgical tactics. Level of Evidence II; Prognostic Studies— Investigating the Effect of a Patient Characteristic on the Disease Outcome.

SURGICAL TREATMENT OF LUMBAR DISC HERNIATION IN PREGNANT WOMEN: REPORT OF TWO CASES AND A SYSTEMATIC REVIEW

ABSTRACT Objective: To review the surgical treatment of lumbar disc herniation in pregnancy. Methods: We systematically reviewed cases of surgical treatment of pregnant patients with lumbar IVD herniations in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. We searched on electronic databases, including PubMed, Scopus, and Google Scholar, to find relevant articles by keywords. Results: A literature review of 42 cases is presented. Conclusions: The authors’ own data and the literature data demonstrate that decompression surgery in pregnancy is effective and safe for both mother and fetus; however, radical surgery (fusion) can lead to very adverse sequelae for the fetus. Level of Evidence III; Systematic reviewb of Level III studies.

Fusion Techniques Are Related to a Lower Risk of Reoperation in Lumbar Disc Herniation: A 5-Year Observation Study of a Nationwide Cohort in Taiwan

OBJECTIVE

Lumbar disc herniation (LDH) is a common spinal problem, with reoperation rates of 6%-24%. Although different surgical techniques are used for treatment, there is still debate regarding whether fusion techniques can reduce the reoperation rate in patients with LDH.

METHODS

This retrospective study used a 5-year nationwide database to analyze reoperation rates in Taiwan. Patient age groups (≥20 and <90 years) treated by index surgery and reoperation for LDH were identified. Four surgical procedures were included in the analysis: discectomy (DC), anterior lumbar fusion with DC (FA + DC), posterior lumbar fusion (FP), and posterior lumbar fusion with DC (FP + DC).

RESULTS

There were 1743 index surgeries between 2008 and 2012, with 184 (10.56%) reoperations. Index surgery DC had the highest reoperation rate (n = 121, 20%). The reoperation risk was significantly lower for patients undergoing fusion procedures (FA + DC vs. DC [hazard ratio (HR), 0.24; 95% confidence interval (CI), 0.12-0.47; P < 0.01], FP versus DC [HR, 0.17; 95% C, 0.09-0.33; P <0.01], FP + DC versus DC [HR, 0.31; 95% CI, 0.22-0.44; P < 0.01]). Fusion procedures had significantly higher treatment costs compared with DC (FA + DC vs. FP vs. FP + DC vs. DC: 5851.74 ± 4808.94 vs. 5116.88 ± 3428.97 vs. 4782.16 ± 2902.19 vs. 3846.79 ± 3584.45 U.S. dollars/patient, respectively; P < 0.0001).

CONCLUSIONS

Among surgical procedures for LDH, fusion techniques are related to lower reoperation rates compared with discectomy, but at the expense of higher medical costs.

Patients at the Highest Risk for Reherniation Following Lumbar Discectomy in a Multicenter Randomized Controlled Trial

Background

The purposes of the present study were to (1) confirm the risk of recurrent lumbar disc herniation in patients with a large anular defect who had undergone limited discectomy and (2) assess potential risk factors within this population.

Methods

The patient population was extracted from the control cohort of a prospective, randomized, multicenter controlled trial investigating the efficacy of an anular closure device following standard limited discectomy. All control patients underwent limited discectomy for the treatment of a single-level symptomatic posterior or posterolateral lumbar disc herniation. Only patients presenting with a large anular defect (6 to 10 mm wide by 4 to 6 mm long) were included in the study (n = 278). Baseline demographic, clinical, and surgical characteristics were recorded. Follow-up evaluations were performed at 6 weeks and at 3, 6, 12, and 24 months. Imaging modalities included magnetic resonance imaging, low-dose computed tomography, and radiographs. Symptomatic recurrent lumbar disc herniation was defined as any symptomatic postoperative herniation on either side of the index level. A multivariate logistic regression analysis of demographic and surgical variables associated with the incidence of recurrent lumbar disc herniation was performed.

Results

The mean anular defect area (and standard deviation) was 39.3 ± 9.1 mm², and the mean excised nuclear tissue volume was 1.3 ± 0.8 mL. At 2 years, the incidence of symptomatic recurrent lumbar disc herniation was 25.3% (64 of 253), with the herniation occurring at a mean of 264 days after the index procedure. Of the 64 patients with recurrent lumbar disc herniation, 36 underwent a subsequent surgical procedure. Logistic regression analysis identified an increased risk for recurrent lumbar disc herniation in females (odds ratio, 2.2) and in patients with greater anular defect widths (odds ratio, 1.3). Furthermore, multivariate logistic regression analyses revealed a significant interaction between age and sex (p = 0.005).

Conclusions

The outcomes of the present study provide the most substantial evidence to date in confirming previous reports of a high risk of reherniation among patients with large anular defects. Among those with large anular defects (width, ≥6 mm), females ≤50 years of age had the highest risk (up to ∼10 times higher) of recurrent lumbar disc herniation. It is recommended that an anular repair or closure should be performed after limited discectomies in patients with large anular defects.

Level of Evidence

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Selection of Tubular and Endoscopic Transforaminal Disc Procedures Based on Disc Size, Location, and Characteristics

The clinical effectiveness of percutaneous and transforaminal endoscopic discectomy procedures has been evaluated by the system used or compared to open laminectomy or micro-discectomy but are not evaluated based on the location and characteristics of the abnormal disc. This review proposes that outcomes are primarily related to disc size, biomechanics, location, and associated segmental fibrotic and bone changes as well as the surgeon's skill in using various systems rather than the specific system used. In these cases, the surgeon needs to decide if the goal of the procedure is simply internal decompression of an abnormal but contained herniated disc or release of the entrapped nerve root by a large contained disc, extruded and migrated disc fragment, or coexistent foraminal stenosis. Percutaneous and tubular transforaminal procedures are quite different, technically ranging from simple discectomy aspirating probes to larger endoscopic systems, providing the capability to remove large extruded free disc fragments, with or without foraminotomy. Recently, the ability to perform interbody fusion has been added to the range of procedures able to be performed endoscopically. At the same time, biologic solutions to disc degeneration are rapidly evolving and may have a place in combination with these procedures. This article reviews the interrelationship between clinical signs and symptoms, radiologic findings, and the biochemistry and biomechanics of the affected disc segment. Understanding the role played by all these factors enables the surgeon to evaluate both the disc and surrounding bone structures pre-operatively to determine if the clinical signs and symptoms are related to enlargement and displacement of a contained disc or compression or impingement of the nerve root. Based on this, the surgeon can choose different surgical systems, allowing simple decompression of a contained disc, possibly adding biologics, with a 'small' system, while a large herniated disc, or extruded fragment, causing root impingement, would require a ‘larger’ system that provides direct endoscopic visualization within the epidural space, foraminal decompression with drills, and direct surgical manipulation and freeing of the nerve root. By choosing the surgical system based on characteristics such as disc size, location, and associated inflammatory and fibrotic changes, the effectiveness of minimally invasive procedures will be more consistent and improve as the surgeon's diagnostic and operative skills improve.

Lumbar Disc Herniation

PURPOSE OF REVIEW

Substantial advancements have been made in the cause, diagnosis, imaging, and treatment options available for patients with lumbar disc herniation (LDH). We examined the current evidence and highlight the concepts on the frontline of discovery in LDH.

RECENT FINDINGS

There are a myriad of novel etiologies of LDH detailed in recent literature including inflammatory factors and infectious microbes. In the clinical setting, recent data focuses on improvements in computer tomography as a diagnostic tool and non-traditional injection options including tumor necrosis alpha inhibitors and platelet-rich plasma. Operative treatment outcomes have focused on minimally invasive endoscopic approaches and demonstrated robust 5-year post-operative outcomes. Advances in the molecular etiology of LDH will continue to drive novel treatment options. The role of endoscopic treatment for LDH will continue to evolve. Further research into10-year outcomes will be necessary as this surgical approach continues to gain widespread popularity.

RESULTS OF TOTAL LUMBAR INTERVERTEBRAL DISK REPLACEMENT WITH M6-L: A MULTICENTER STUDY

ABSTRACT Objective: In this paper we report the clinical and radiological results of lumbar intervertebral disk (IVD) replacement with M6-L for the treatment of patients with IVD degeneration. Methods: One hundred and fifty-six patients with IVD degeneration were operated with the one level implantation of an M6-L prosthesis at three neurosurgical departments, in Irkutsk, Krasnoyarsk and Vladivostok. We assessed pain intensity (VAS), the Oswestry disability index (ODI) and outcomes by the Macnab scale up to 36 months after surgery. Instrumental data were used to assess range of motion in the operated segment and heterotopic ossification by the McAfee-Suchomel classification. Results: The average VAS before surgery was 6.9 ± 1.6 cm. After surgery, this value reduced significantly, to an average of 1.3 ± 1.2 cm (p<0.001). The average ODI before surgery was 40.2 ± 6.9%, and after IVD arthroplasty, this indictor improved to 12.3 ± 6.1% (p <0.001). Range of motion in the operated segment at baseline averaged 36.8 ± 2.6o, and within 36 months after the operation, this had increased to 41.2 ± 2.9o. During the entire follow-up period, signs of severe (13.4%, n = 21) or moderate (10.2%, n = 16) heterotopic ossification were observed. Conclusions: The use of M6-L prosthesis can significantly reduce the level of pain, improve quality of life and maintain the physiological range of motion in the operated spinal segment in patients with degenerative lesions IVD at a low level of adverse outcomes. [249 Words].