Impact of Preoperative Intervertebral Disc Degeneration on Patient-Reported Outcome Measures After Lumbar Fusion.

OBJECTIVE: The Pfirrmann scoring system classifies lumbosacral disc degeneration based on MRI signal intensity. The relationship between pre-existing disc degeneration and PROMs after one-level lumbar fusion is not well documented. The purpose of this study was to investigate the relationship between the severity of preoperative intervertebral disc degeneration and pre- and postoperative patient-reported outcome measures (PROMs) in patients undergoing one-level lumbar fusion. METHODS: All adult patients underwent posterior lumbar decompression and fusion (PLDF) or transforaminal lumbar interbody fusion (TLIF) between 2014-2022 were included. Patient demographics, and comorbidities were extracted from medical records. Lumbar intervertebral discs on sagittal MRI T2-weighted images were assessed by two independent graders utilizing Pfirrmann criteria. Grades I-III were categorized as low-grade disc degeneration, while IV-V were considered high-grade. Multivariable linear regression assessed the impact of disc degeneration on PROMS. RESULTS: A total of 150 patients were included, of which, 69 (46%) had low grade disc degeneration, while 81 (54%) had high grade degeneration. Patients with high-grade degeneration had increased preoperative VAS-Leg scores (6.10 vs. 4.54, p=0.005) and displayed greater one-year postoperative improvements in VAS-Back scores (-2.11 vs -0.66, p=0.002). Multivariable regression demonstrated Pfirrmann scores as independent predictors for both preoperative VAS-Leg scores (p=0.004) and postoperative VAS-Back improvement (p=0.005). CONCLUSIONS: In patients undergoing one-level lumbar fusion, higher Pfirmann scores were associated with increased preoperative leg pain and greater one-year postoperative improvement in back pain. Further studies into the relationship of pre-operative disc degeneration and their impact on postoperative outcomes may help guide clinical decision making and patient expectations.

Serum Endothelin-1 Level Can Reflect the Degree of Lumbar Degeneration: A Cross-Sectional Study.

Background Endothelin-1 (ET-1) is an agent closely associated with inflammation and has recently been recognized as a significant factor in degenerative processes. This study aimed to investigate the correlation between serum ET-1 level and radiological and clinical manifestations of lumbar disc herniation (LDH) and intervertebral disc degeneration (IDD) pathologies. Methodology The study was conducted with 50 healthy controls and 50 LDH patients. The pain level of the patients was analyzed with the Visual Analog Scale (VAS), and their functionality was analyzed with the Oswestry Disability Index (ODI). The disc degeneration and disc herniation grades were determined using magnetic resonance imaging. Serum ET-1 levels of the participants were measured using the enzyme-linked immunosorbent assay method. Results ET-1 level was significantly higher in the patient group compared to the controls (p < 0.01). A positive correlation was determined between serum ET-1 level and Pfirrmann grade in the patient group (p < 0.01). No correlation was determined between the MacNab grade, VAS, and ODI scores and ET-1 (p = 0.397, p = 0.137, and p = 0.208, respectively). There was no significant difference between the serum ET-1 levels of the patients with or without neurological deficits (p = 0.312). Conclusions The correlation between the serum ET-1 levels and IDD grade suggested that the former could serve as a biomarker to determine the degree of degeneration in the future. However, further research is required to determine the underlying mechanisms.

A fully automatic MRI-guided decision support system for lumbar disc herniation using machine learning.

Background: Normalized decision support system for lumbar disc herniation (LDH) will improve reproducibility compared with subjective clinical diagnosis and treatment. Magnetic resonance imaging (MRI) plays an essential role in the evaluation of LDH. This study aimed to develop an MRI-based decision support system for LDH, which evaluates lumbar discs in a reproducible, consistent, and reliable manner. Methods: The research team proposed a system based on machine learning that was trained and tested by a large, manually labeled data set comprising 217 patients' MRI scans (3255 lumbar discs). The system analyzes the radiological features of identified discs to diagnose herniation and classifies discs by Pfirrmann grade and MSU classification. Based on the assessment, the system provides clinical advice. Results: Eventually, the accuracy of the diagnosis process reached 95.83%. An 83.5% agreement was observed between the system's prediction and the ground-truth in the Pfirrmann grade. In the case of MSU classification, 95.0% precision was achieved. With the assistance of this system, the accuracy, interpretation efficiency and interrater agreement among surgeons were improved substantially. Conclusion: This system showed considerable accuracy and efficiency, and therefore could serve as an objective reference for the diagnosis and treatment procedure in clinical practice.

Quantitative evaluation of disc degeneration using dual-energy CT: advantages of R-VH, D-VH values and the IVNCa + CT model.

OBJECTIVE: To evaluate the correlation between dual-energy CT (DECT) virtual calcium free (VNCA), CT attenuation, the ratio and difference of VNCA to CT attenuation, and Pfirrmann grading of lumbar disc degeneration. METHODS: A retrospective analysis on 135 intervertebral discs from 30 patients who underwent DECT and MR. Discs was graded using the Pfirrmann system. ROIs on the sagittal plane assessed HU value, VNCA value, Rho value, Z value, R-VH value, and D-VH value. Correlation, grade differences, and multivariate regression models were assessed. Diagnostic performance and cut-off values were determined using AUC. RESULTS: VNCA (r = 0.589, P < 0.001), R-VH (r = 0.622, P < 0.001), and D-VH (r = 0.613, P < 0.001) moderately correlated with Pfirrmann grading. HU (r = 0.388, P < 0.001), Rho (r = 0.142, P = 0.102), and Z (r = -0.125, P = 0.153) showed a weak correlation. R-VH, D-VH, and VNCA had significantly higher correlation than HU. Statistically significant differences were observed in P values of VNCA, HU, R-VH, and D-VH in relative groups (P < 0.05), but not in Rho and Z values (P > 0.05). R-VH and D-VH had significant differences between Pfirrmann grades 1 and 2, and grades 2 and 3 (early stage) (P < 0.05). AUC readings of R-VH and D-VH (≥2, ≥3, ≥4) were higher. The multivariate model IVNCa + CT had the highest AUC. CONCLUSION: The new quantitative indices R-VH value and D-VH value of DECT have advantages over VNCA value and HU value in evaluating early-stage disc degeneration (≥2 grades, ≥3 grades). The multivariate model IVNCa + CT has the best AUC values for evaluating disc degeneration at all stages.

The Impacts of Intervertebral Disc Degeneration of the Spine, Alcohol Consumption, Smoking Tobacco Products, and Glycemic Disorders on the Expression Profiles of Neurotrophins-3 and -4.

In the etiology of discogenic pain, attention is paid to the role of neurotrophic factors, which include classic neurotrophins (NTs). This study aimed to assess changes in the concentrations of NT-3 and NT-4 in the intervertebral discs (IVDs) of the lumbosacral (L/S) spine depending on the advancement of degenerative changes, pain severity, habits, and comorbidities. The study group included 113 patients who underwent microdiscectomy due to degenerative IVD disease of the L/S spine. The severity of degenerative IVD changes was assessed using the five-point Pfirrmann scale, and the pain intensity was assessed according to the visual analog scale (VAS). In turn, the control group included 81 participants from whom IVDs of the L/S section of the spine were collected post-mortem during forensic autopsy or organ donation. At the mRNA level, we noted NT-3 overexpression in the test samples compared with the controls (fold change (FC) = 9.12 ± 0.56; p < 0.05), while NT-4 transcriptional activity was decreased in the test samples compared with the controls (FC = 0.33 ± 0.07; p < 0.05). However, at the protein level, the concentrations of NT-3 (134 ± 5.78 pg/mL vs. 6.78 ± 1.17 pg/mL; p < 0.05) and NT-4 (316.77 ± 8.19 pg/mL vs. 76.92 ± 4.82 pg/mL; p < 0.05) were significantly higher in the test samples compared with the control samples. Nevertheless, the concentration of both proteins did not statistically significantly change depending on the advancement of degenerative changes and the pain intensity (p > 0.05). In addition, higher levels of NT-3 and NT-4 were noted in IVD samples from patients who consumed alcohol, smoked tobacco, were overweight/obese, or had comorbid diabetes compared with patients without these risk factors (p < 0.05). Our analysis confirmed that differences in the degenerative process of IVD, energy metabolism, and lifestyle are related to changes in the concentration profiles of NT-3 and NT-4.

MRI characteristics of disc degeneration after condoliase injection in young patients: A consecutive case series.

BACKGROUND: Lumbar disc herniation (LDH) results in low back pain due to nerve root compression caused by nucleus pulposus degeneration. Chemonucleolysis of the nucleus pulposus by injection of condoliase is less invasive than surgery, but may cause disc degeneration. The purpose of the study was to examine outcomes of condoliase injection in patients in their teens and twenties using Pfirrmann criteria on MRI. METHODS: A single-center retrospective study was performed in 26 consecutive patients (19 men, 7 women) who underwent condoliase injection (1 mL, 1.25 U/mL) for LDH and had MRI scans at 3 and 6 months. Cases with and without an increase in Pfirrmann grade at 3 months post-injection were included in groups D (disc degeneration, n = 16) and N (no degeneration, n = 10). Pain was measured on a visual analogue scale (VAS). MRI findings were evaluated using the % change in disc height index (ΔDHI). RESULTS: The mean age of the patients was 21.1 ± 4.1 years and 12 were <20 years old. At baseline, 4, 21 and 1 were in Pfirrmann grades II, III and IV. In group D, no case had a further increase in Pfirrmann grade from 3 to 6 months. Pain significantly decreased in both groups. There were no adverse events. MRI showed a significant decrease in ΔDHI from 100% pre-injection to 89.4 ± 9.7% at 3 months in all cases (p < 0.05). There was a significant recovery in ΔDHI in group D from 3 to 6 months (85.4 ± 9.3% vs. 86.7 ± 9.1%, p < 0.05). CONCLUSIONS: These results suggest that chemonucleolysis with condoliase is effective and safe for LDH in young patients. Progression of Pfirrmann criteria at 3 months post-injection occurred in 61.5% of cases, but disc degeneration showed recovery in these patients. A longer-term study of the clinical symptoms related to these changes is required.

Prevalence of degenerative vertebral disc changes in elite female Crossfit athletes - a cross-sectional study.

BACKGROUND: Crossfit athletes consistently recruit or transfer high levels of repetitive forces through the spine, and MRI has documented a higher rate of intervertebral disc degeneration in athletes compared with matched controls. The aim of this study was to evaluate early degenerative spinal disc changes in elite female CrossFit athletes quantified by 3.0 Tesla magnetic resonance imaging (MRI) matched with female none-athletes. METHODS: In a cross-sectional single-center study 19 asymptomatic adult participants, nine German female elite Crossfit athletes and ten female participants underwent spinal MRI (3.0T). Demographic data, spinal clinical examination results and sport-specific performance parameters were collected prior to the MRI. The primary outcome was the prevalence of degenerative spinal disc changes. The secondary outcome was the grade of degeneration using Pfirrmann grading. RESULTS: A total of 437 discs underwent spinal MRI (3.0T). The prevalence of early degenerative disc disease was not increased. Pfirrmann degenerative grade did not show significant differences among groups. CONCLUSION: Asymptomatic female elite Crossfit athletes do not show an increased prevalence of degenerative disc disease. Compared to a sex-matched control group, high training volume in Crossfit does not correlate to a higher incidence of degenerative disc changes in young females.

The Comparison between Herniated and Non-Herniated Disc Levels Regarding Intervertebral Disc Space Height and Disc Degeneration, A Magnetic Resonance Study.

PURPOSE: The main purpose of this study was to evaluate the intervertebral disc height and intervertebral disc degeneration between the normal group and the group with disc herniation at the level of the L4-L5 intervertebral disc by MRI using the Pfirrmann grading system. MATERIALS AND METHODS: 385 patients were included in this study. MRI images were reevaluated and intervertebral disc heights were measured from the anterior, middle and posterior segments. Researchers divided disc pathologies into two groups. In the non-herniated group; normal or bulging ones; in the herniated group, they included those with protrusion or extrusion. RESULTS: 385 lumbar MRI examinations meeting the study criteria were included in study. There were 56.9% (219/385) females and 43.1% (166/385) males in the study. For the whole patients in the study group, the intervertebral disc height values at the L4-5 level were measured as 12.34 mm, 11.58 mm, and 7.60 mm in the anterior, middle, and posterior localizations, respectively. CONCLUSIONS: At the L4-5 level, the height of the disc distances in the herniated group was lower than in the normal group. The Pfirrman score was found to be higher in the herniated group in terms of disc degeneration compared to the normal group.

Risk Factors in Patients with Low Back Pain Under 40 Years Old: Quantitative Analysis Based on Computed Tomography and Magnetic Resonance Imaging mDIXON-Quant.

Purpose: While low back pain (LBP) constitutes a global life disorder cause, the contribution of paraspinal muscles to its pathogenicity remains elusive. We characterized the paraspinal muscles of patients with LBP using lumbar three-dimensional computed tomography (CT) and magnetic resonance imaging (MRI) mDIXON-Quant, and evaluated the risk factors combined with clinical data. Methods: A retrospective study involving 181 patients (10-40 years) who underwent lumbar 3D-CT and MRI mDIXON from January 1, 2021 to December 31, 2022, and divided into normal, non-chronic LBP [non-CLBP], and CLBP groups. Clinical data, paraspinal muscle cross-sectional area, Hounsfield unit for CT values, and fat fraction derived from mDIXON-Quant were compared. Three readers analyzed the images independently; intra- and interobserver agreement was measured. Spearman analysis and multiple logistic regression were used to analyze the correlation between clinical data, radiologic and paraspinal muscle parameters. A nomogram was constructed for individualized prediction. Results: Correlation analysis revealed that body mass index, visual analog scale score, Pfirrmann grade, annulus fibrosus tear, lumbar lordosis (LL), and Modic changes correlated with LBP (all P<0.05). The Pfirrmann grade and annulus fibrosus tear showed positive correlation (r=0.673, 0.559), whereas LL was negatively correlated (r=-0.469). The multifidus CT values were negatively correlated with LBP at L4-5/L5-S1; the multifidus fat fraction was positively correlated at L4-5/L5-S1 (r=0.734, r=0.584, P<0.001). The multiple logistic regression showed that L4-5 multifidus fat fraction (P=0.046, OR=1.167), Pfirrmann grade (P=0.017, OR=0.063), LL (P=0.002, OR=0.828) and annulus fibrosus tear (P=0.005, OR=0.024) were risk factors for predicting LBP in the non-CLBP group; in the CLBP group, BMI (P=0.048 OR=1.225), L4-5 multifidus fat fraction (P=0.001 OR=1.299), LL (P=0.003, OR=0.841) and Pfirrmann classification (P=0.009, OR=0.046) were risk factors. Conclusion: BMI, L4-5 multifidus fat fraction, LL, and Pfirrmann grade are risk factors for CLBP in patients under 40; whereas annulus fibrosus tear is an independent risk factor for non-CLBP, nomograms derived from these parameters can help predict LBP and MRI mDIXON-Quant is recommended for quantitatively analyzing paraspinal muscle fat infiltration.

An Automatized Deep Segmentation and Classification Model for Lumbar Disk Degeneration and Clarification of Its Impact on Clinical Decisions.

STUDY DESIGN: Cross-sectional database study. OBJECTIVE: The purpose of this study was to develop a successful, reproducible, and reliable convolutional neural network (CNN) model capable of segmentation and classification for grading intervertebral disc degeneration (IVDD), as well as quantify the network's impact on doctors' clinical decision-making. METHODS: 5685 discs from 1137 patients were graded separately by four experienced doctors according to the Pfirrmann classification. A ground truth (GT) was established for each disc in accordance with the decision of the majority of doctors. The U-net model is used for segmentation. 1815 discs from 363 patients were used to train and test the U-net. The Inception V3 model is employed for classification. All discs were separated into two distinct sets: 90% in a training set and 10% in a test set. The performance metrics of these models were measured. Reliability tests were performed. The impact of CNN assistance on doctors was assessed. RESULTS: Segmentation accuracy was .9597 with a .8717 Jaccard Index and a .9314 Sorensen Dice coefficient. Classification accuracy is .9346, and the F1 score is .9355. The intraclass correlation coefficient (ICC) and kappa values between CNN and GT were .95-.97. With CNN's assistance, the success rates of doctors increased by 7.9% to 22%. CONCLUSIONS: The fully automated network outperformed doctors markedly in terms of accuracy and reliability. The results of CNN were comparable to those of other recent studies in the literature. It was determined that CNN's assistance had a substantial positive effect on the doctor's decision.

Apparent diffusion coefficient and T2* mapping on 3T MRI in normal and degenerative lumbar intervertebral discs.

Purpose: To assess the utility of diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) maps and T2* mapping in quantitative analysis of nucleus pulposus (NP) and annulus fibrosus (AF) of lumbar intervertebral discs with its correlation with modified Pfirrmann grading (MPG) for lumbar degenerative disc disease (LDDD). Material and methods: One hundred subjects (20-74 years of age) underwent T2-weighted, DWI with ADC and T2* magnetic resonance imaging. MPG was applied to L3-L4, L4-L5, and L5-S1 discs, and ADC and T2* values of NP and AF were calculated in the mid-sagittal plane by segmenting each disc into 5 regions of interest (ROI) (NP-3, AF-2). Mean ADC and T2* values, their correlation, and cut-offs among different grades were calculated at different ROIs across different levels. Results: Out of total 300 discs analysed; 68 were normal (grade I) discs and 232 were degenerated (grade II to VIII) discs, based on MPG. T2* and ADC values in NP, AF, and the entire disc were significantly lower in degenerated discs than in normal discs. There was significant (p < 0.001) negative correlation between ADC and T2* values with MPG. ADC and T2* cut-off values were statistically significant across grades, with area under the curve (AUC) values in moderate to high accuracy range (0.8 to > 0.9) for assessing the degree of LDDD. Conclusions: T2* and ADC value-based grade scales are highly accurate in evaluating the degree of disc degeneration with a high degree of objectivity in comparison to visual assessment-based MPG. Reduced ADC and T2* values of NP could serve as markers of early LDDD.

The lumbar spinal endplate lesions grades and association with lumbar disc disorders, and lumbar bone mineral density in a middle-young general Chinese population.

BACKGROUND: Lumbar vertebral endplates lesions (LEPLs), one of the etiologies of low back pain (LBP), are one of the most prevalent causes of health-care costs. Despite progressively becoming the focus in recent years, almost all studies have concentrated on symptomatic patients rather than general populations. As a result, our study was designed to determine the prevalence and distribution patterns of LEPLs in a middle-young general population, as well as their associations with lumbar disc herniation (LDH), lumbar disc degeneration (LDD), and lumbar vertebral volumetric bone mineral density (vBMD). METHODS: Seven hundred fifty-four participants aged 20-60 years were recruited from the subjects enrolled in a 10-year longitudinal study of degeneration of the spine and knee being conducted at the Beijing Jishuitan Hospital and 4 of them were excluded due to the missing of MRIs. In this observational study, a lumbar quantitative computed tomography (QCT) and MRI scan were performed among participants within 48 h. T2-weighted sagittal lumbar MRI images for all included subjects were identified for LEPLs by two independent observers based on morphological and local characteristics. Lumbar vertebral vBMD was measured with QCT. The age, BMI, waistline, hipline, lumbar vBMD, LDD, and LDH were measured to investigate their associations with LEPLs. RESULTS: The prevalence of LEPLs was higher among the male subjects. 80% of endplates were recognition as no lesions with a substantial disparity between female (75.6%) and male subjects (83.4%) (p < 0.001). The most common lesions were "wavy/irregular" and "notched", and "fracture" is most involved in L3-4 inferior endplate both in two genders. LEPLs were found to be associated with LDH (≥ 2 levels: OR = 6.859, P < 0.001; 1 level: OR = 2.328, P = 0.002 in men. OR = 5.004, P < 0.001; OR = 1.805, P = 0.014 in women) reference for non-LDH, and hipline in men (OR = 1.123, P < 0.001). CONCLUSIONS: LEPLs are the common findings on lumbar MRIs in general population, particularly in men. The presence of these lesions and advance from slightly to severely could be mainly attributed to LDH and men's higher hipline.

Ultra-short echo time MR imaging in assessing cartilage endplate damage and relationship between its lesion and disc degeneration for chronic low back pain patients.

OBJECTIVE: To investigate the feasibility of ultra-short echo time (UTE) magnetic resonance imaging (MRI) in the assessment of cartilage endplate (CEP) damage and further evaluate the relationship between total endplate score (TEPS) and lumbar intervertebral disc (IVD) degeneration for chronic low back pain patients. MATERIALS AND METHODS: IVD were measured in 35 patients using UTE imaging at 3T MR. Subtracted UTE images between short and long TEs were obtained to depict anatomy of CEP. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated to assess the image quality quantitatively. A new grading criterion for endplate damage evaluation was developed based on Rajasekaran.S grading system in this study. Two radiologists were employed to evaluate CEP and bony vertebral endplates (VEP) using this new grading criterion and assess TEPS, independently. Cohen's kappa analysis was applied to evaluate the inter-observer agreement of endplate damage assessment between two radiologists, and the Kendall's TAU-B analysis was employed to determine the relationship between TEPS and IVD degeneration evaluated with Pfirrmann grading. RESULTS: Well structural CEP was depicted on subtracted UTE images and confirmed by high SNR (33.06±2.92) and CNR values (9.4±2.08). Qualified subtracted UTE images were used by two radiologists to evaluate the degree of CEP and VEP damage. Excellent inter-observer agreement was confirmed by high value in Cohen's kappa test (0.839, P < 0.001). Ensured by this, 138 endplates from 69 IVDs of 35 patients were classified into six grades based on the new grading criterion and TEPS of each endplate was calculated. In addition, the degeneration degree of IVDs were classified into five grades. Finally, using Kendall's TAU-B analysis, significant relationship was obtained between endplate damage related TEPS and IVD degeneration (r = 0.864, P < 0.001). CONCLUSION: Ensured by high image quality, UTE imaging might be considered an effective tool to assess CEP damage. Additionally, further calculated TEPS has shown strong positive association with IVD degeneration, suggesting that the severity of endplate damage is highly linked with the degree of IVD degeneration.

ISSLS PRIZE in Clinical Science 2023: comparison of degenerative MRI features of the intervertebral disc between those with and without chronic low back pain. An exploratory study of two large female populations using automated annotation.

OBJECTIVES: The relationship of degeneration to symptoms has been questioned. MRI detects apparently similar disc degeneration and degenerative changes in subjects both with and without back pain. We aimed to overcome these problems by re-annotating MRIs from asymptomatic and symptomatics groups onto the same grading system. METHODS: We analysed disc degeneration in pre-existing large MRI datasets. Their MRIs were all originally annotated on different scales. We re-annotated all MRIs independent of their initial grading system, using a verified, rapid automated MRI annotation system (SpineNet) which reported degeneration on the Pfirrmann (1-5) scale, and other degenerative features (herniation, endplate defects, marrow signs, spinal stenosis) as binary present/absent. We compared prevalence of degenerative features between symptomatics and asymptomatics. RESULTS: Pfirrmann degeneration grades in relation to age and spinal level were very similar for the two independent groups of symptomatics over all ages and spinal levels. Severe degenerative changes were significantly more prevalent in discs of symptomatics than asymptomatics in the caudal but not the rostral lumbar discs in subjects < 60 years. We found high co-existence of degenerative features in both populations. Degeneration was minimal in around 30% of symptomatics < 50 years. CONCLUSIONS: We confirmed age and disc level are significant in determining imaging differences between asymptomatic and symptomatic populations and should not be ignored. Automated analysis, by rapidly combining and comparing data from existing groups with MRIs and information on LBP, provides a way in which epidemiological and 'big data' analysis could be advanced without the expense of collecting new groups. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Evaluation of the concentration of selected elements in serum patients with intervertebral disc degeneration.

Quantitative analysis of the trace element content of human intervertebral discs (IVDs) is essential because it can identify specific enzymes or metabolites that may be related to human intervertebral disc degeneration (IVDD). The goal of this study was to assess the concentrations of copper (Cu), iron (Fe), manganese (Mn), lead (Pb), zinc (Zn), sodium (Na), magnesium (Mg), potassium (K), phosphorus (P), and calcium (Ca) in serum samples obtained from patients with IVDD in comparison to healthy volunteers (a control group). The study group consisted of 113 Caucasian patients qualified by a specialist neurosurgeon for microdiscectomy. The control group consisted of 113 healthy volunteers who met the eligibility criteria for blood donors. The examined clinical material was the serum samples obtained from both groups.Based on the quantitative analysis of selected elements, there were statistically significantly (p 0.05) higher concentrations of Cu (1180 µg/L±800 µg/L vs. 1230 µg/L±750 µg/L), Zn (790 µg/L±300 µg/L vs. 850 µg/L±200 µg/L), and Mg (21730 µg/L±4360 µg/L vs. 23820 µg/L±4990 µg/L) in the serum of healthy volunteers compared to those in the study group. In addition, statistically significant changes were not detected in the concentrations of any elements among either sex in either the study or control group or in their body mass index (BMI) values (p > 0.05). In the serum samples from the study group, the strongest relationships were noted between the concentrations of Zn and Pb (r = 0.61), Zn and P (r = 0.69), Zn and Ca (r = 0.84), Zn and Cu (r = 0.83), Mg and Ca (r = 0.74), and Ca and P (r = 0.98).It has been indicated that, above all, the concentrations of Cu, Zn, Ca, and Mg depend on the advancement of radiological changes, according to the Pfirrmann scale. However, no influence on pain intensity was found, depending on the concentration of the assessed elements.The analysis indicates that the determination of serum Cu, Zn, Ca, and Mg concentrations may have diagnostic significance in predicting the onset of lumbosacral IVDD. The predictive evaluation of changes in the concentrations of selected elements in patients with degenerative lumbar IVD lesions appears to be a promising, cost-effective strategy.

Factors associated with disc degeneration based on Pfirrmann criteria after condoliase treatment for lumbar disc herniation.

BACKGROUND: Lumbar disc herniation (LDH) is a common cause of low back pain and is associated with degeneration of the nucleus pulposus causing nerve root compression. Chemonucleolysis of the nucleus pulposus with condoliase is a low-invasive treatment for LDH. The purpose of this study was to investigate changes in Pfirrmann criteria, which are used to evaluate disc degeneration, after injection of condoliase into a herniated intervertebral disc, and to identify factors associated with disc degeneration at 3 months post-injection. METHODS: Medical records and radiographic findings were reviewed retrospectively for 127 patients with LDH (88 male, 39 female, mean age: 46.6 ± 17.1 years, mean follow-up: 9.8 ± 7.8 months) who underwent chemonucleolysis with intradiscal condoliase injection at our center since September 2018. Condoliase (1.25 U/mL; 1 mL volume) was injected toward the middle of the affected intervertebral nucleus pulposus using a 21-gauge disc-puncture needle. RESULTS: Cases in which the Pfirrmann grade did and did not progress in the 3 months after the injection were included in groups P (progression, n = 49) and NP (non-progression, n = 78), respectively. Logistic regression analysis of progression of Pfirrmann grade post-injection showed significant associations with age <40 years (p = 0.013, odds ratio (OR): 3.69, 95% confidence interval (CI): 1.32-10.31), Pfirrmann Grade II or III at baseline (p = 0.021, OR: 3.51, 95% CI: 1.24-9.64), and a high-intensity MRI signal in the herniation (p = 0.047, OR: 2.97, 95% CI: 1.03-8.87). Patients in group P had significantly higher rates of disc height decrease ≥20%, reduced herniated disc size, and improved VAS for pain, but both groups had significant decreases in pain. No cases had anaphylactic shock or neurologic sequelae. CONCLUSIONS: These results show the safety and efficacy of chemonucleolysis with condoliase for treatment of painful LDH. Progression of Pfirrmann criteria on MRI at 3 months after injection was significantly associated with an improved clinical outcome.

The Lumbar Facet Capsular Ligament Becomes More Anisotropic and the Fibers Become Stiffer With Intervertebral Disc and Facet Joint Degeneration.

Degeneration of the lumbar spine, and especially how that degeneration may lead to pain, remains poorly understood. In particular, the mechanics of the facet capsular ligament may contribute to low back pain, but the mechanical changes that occur in this ligament with spinal degeneration are unknown. Additionally, the highly nonlinear, heterogeneous, and anisotropic nature of the facet capsular ligament makes understanding mechanical changes more difficult. Clinically, magnetic resonance imaging (MRI)-based signs of degeneration in the facet joint and the intervertebral disc (IVD) correlate. Therefore, this study examined how the nonlinear, heterogeneous mechanics of the facet capsular ligament change with degeneration of the lumbar spine as characterized using MRI. Cadaveric human spines were imaged via MRI, and the L2-L5 facet joints and IVDs were scored using the Fujiwara and Pfirrmann grading systems. Then, the facet capsular ligament was isolated and biaxially loaded. The nonlinear mechanical properties of the ligament were obtained using a nonlinear generalized anisotropic inverse mechanics analysis (nGAIM). Then a Holzapfel-Gasser-Ogden (HGO) model was fit to the stress-strain data obtained from nGAIM. The facet capsular ligament is stiffer and more anisotropic at larger Pfirrmann grades and higher Fujiwara scores than at lower grades and scores. Analysis of ligament heterogeneity showed all tissues are highly heterogeneous, but no distinct spatial patterns of heterogeneity were found. These results show that degeneration of the lumbar spine including the facet capsular ligament appears to be occurring as a whole joint phenomenon and advance our understanding of lumbar spine degeneration.

Predictable factors for aggravation of cervical alignment after posterior cervical foraminotomy.

OBJECTIVE: This study aimed to investigate the risk factors for aggravation of cervical alignment after posterior cervical foraminotomy (PCF) and to identify their relationships with kyphotic changes in cervical curvature. METHODS: Ninety-eight patients who underwent PCF for unilateral radiculopathy and received follow-up for more than 2 years were retrospectively reviewed. Segmental Cobb angle (SA), cervical Cobb angle (CA), Pfirrmann grade, foraminal stenosis, and clinical outcomes including neck pain, arm pain, and Neck Disability Index scores were assessed. Radiological and clinical outcomes were compared between groups C (control group with kyphotic change in CA < 5°) and K (kyphotic group with kyphotic change in CA ≥ 5°). Multivariate regression analysis was performed to determine the risk factors for kyphotic change ≥ 5° after PCF. RESULTS: Group K was significantly older than group C (p = 0.002) and had a higher Pfirrmann grade (p = 0.025). In group K, neck pain had significantly increased at last follow-up (p < 0.001). Multivariate linear regression analysis revealed that kyphotic changes in CA were related to older age (p = 0.016, B = 0.420) and Pfirrmann grade of the operative levels (p = 0.032, B = 4.560). Preoperative hypolordosis was not an independent risk factor for kyphotic changes in CA. Receiver operating characteristic curve analysis showed that the cutoff value for kyphotic changes in patients with CA ≥ 5° was Pfirrmann grade 3.417 (p = 0.008). CONCLUSIONS: Contrary to previous studies, preoperative hypolordosis was not a risk factor for kyphotic changes in CA after PCF. Older patients with disc degeneration of Pfirrmann grade IV or greater for should be carefully considered.

Disc degeneration contributes to the denser bone in the subendplate but not in the vertebral body in patients with lumbar spinal stenosis or disc herniation.

BACKGROUND CONTEXT: It is commonly believed that decreased bone quality would lead to endplate degeneration and arthritic changes in the facet joints, and thus accelerated disc degeneration (DD). However, some more detailed studies of vertebral bone structure have found that bone mineral density (BMD) in the vertebral body is increased rather than decreased in moderate or greater disc degeneration. The relationship between BMD and DD still needs further study. MRI-based vertebral bone quality scores have been shown to be effective in reflecting BMD, rendering a new way to evaluate the changes of vertebral body bone with DD using MRI alone. PURPOSE: To evaluate MRI-based vertebral bone quality and Pfirrmann grades in patients with lumbar spinal stenosis or disc herniation, and to identify if DD is associated with denser bone around the endplate. STUDY DESIGN/SETTING: A single-center, retrospective cohort study. PATIENT SAMPLE: A total of 130 patients with lumbar disc herniation and lumbar spinal stenosis from January 2019 to November 2020 who had a complete dual-energy X-ray absorptiometry scan and noncontrast lumbosacral spine MRI data. OUTCOME MEASURES: The vertebral bone quality score (VBQ) and sub-endplate bone quality score (EBQ) was calculated as a ratio of the signal intensity of the vertebral bodies and sub-endplate regions to the signal intensity of the cerebrospinal fluid at L3 on the mid-sagittal T1-weighted MRI images, respectively. The Pfirrmann grades of the lumbar discs were assessed as well. METHODS: The age, gender, body mass index, and T-score of the lumbar spine of the patients were collected. The degeneration grades of the lumbar discs were evaluated according to the Pfirrmann classification. VBQ and EBQ were measured through T1-weighted lumbar MRI. The VBQ and EBQ scores were compared between cranial and caudal sides. The correlation between MRI-based bone quality and DD was calculated. A linear regression model was used to examine the association between DD and adjacent EBQ and VBQ. RESULTS: This study included 569 lumbar segments from 130 inpatients. Cranial and caudal EBQ decreased with the increase of the Pfirrmann grade. The discs with Pfirrmann grade 5 had significantly lower caudal EBQ than the discs with Pfirrmann grades 2, 3, and 4. In the osteoporosis patients, the Pfirrmann grades negatively correlated both with the cranial EBQ and caudal EBQ. Pfirrmann grade greater than 4 was an independent contributor to the cranial EBQ, whereas greater than 3 was an independent contributor to the caudal EBQ. CONCLUSIONS: Disc degeneration grades correlated with the EBQ but not with the VBQ. In patients with lumbar spinal stenosis or disc herniation, DD contributes to the denser bone in the sub-endplate, but not in the whole vertebral body.