Ligamentum Flavum Thickness Research Articles

Transthyretin amyloidosis in patients with spinal stenosis who underwent spinal surgery: a systematic review and meta-analysis.

Accumulation of transthyretin amyloids (ATTR) is detected in ligamentum flavum in about 1/3 of patients underwent surgery for spinal stenosis. However, the significance of this finding is not known. The aim of this systematic review and meta-analysis is to analyze the incidence and importance of ATTR in patients with spinal stenosis who underwent spinal surgery. The primary outcome measure was incidence of ATTR in patients with spinal stenosis. English language observational studies published within 10 years period were searched in Pubmed and Taylor and Francis databases. Nine articles were included in the systematic review. The incidence of positive ATTR among patients who underwent lumbar spinal surgery was 48% (95%CI 38-58%). ATTR deposits were found in the lumbar region the most frequently. Seven studies showed that patients with positive ATTR were older than those with negative. Five studies investigated and found a significant relationship between the ligamentum flavum thickness and positive ATTR. Five studies investigated cardiac involvement among patients with positive ATTR. ATTR deposits are frequently found in older patients with spinal stenosis, especially in the lumbar region. The presence of ATTR deposits is related to ligamentum flavum thickness.

Clinical implications of linking microstructure, spatial biochemical, spatial biomechanical, and radiological features in ligamentum flavum degeneration.

The ligamentum flavum (LF) degeneration is a critical factor in spinal stenosis, leading to nerve compression and pain. Even with new treatment options becoming available, it is vital to have a better understanding of LF degeneration to ensure the effectiveness of these treatments. This study aimed to provide insight into LF degeneration by examining the connections between various aspects of LF degeneration, including histology, microstructure, chemical composition, and biomechanics. We analyzed 30 LF samples from 27 patients with lumbar vertebrae, employing magnetic resonance imaging (MRI) to link lumbar disc degeneration grades with fibrosis levels in the tissue. X-ray diffraction (XRD) analysis assessed microstructural alterations in the LF matrix component due to degeneration progression. Instrumented nanoindentation combined with Raman spectroscopy explored the spatial microbiomechanical and biochemical characteristics of the LF's ventral and dorsal regions. Our outcomes revealed a clear association between the severity of LF fibrosis grades and increasing LF thickness. XRD analysis showed a rise in crystalline components and hydroxyapatite molecules with progressing degeneration. Raman spectroscopy detected changes in the ratio of phosphate, proteoglycan, and proline/hydroxyproline over the amide I band, indicating alterations in the extracellular matrix composition. Biomechanical testing demonstrated that LF tissue becomes stiffer and less extensible with increasing fibrosis. Notably, the micro-spatial assessment revealed the dorsal side of the LF experiencing more significant mechanical stress, alongside more pronounced biochemical and biomechanical changes compared to the ventral side. Degeneration of the LF involves complex processes that affect tissue histology, chemical composition, and biomechanics. It is crucial to fully understand these changes to develop new and effective treatments for spinal stenosis. These findings can improve diagnostic accuracy, identify potential biomarkers and treatment targets, guide personalized treatment strategies, advance tissue engineering approaches, help make informed clinical decisions, and educate patients about LF degeneration.

Buckling of the Ligamentum Flavum in Patients with Lumbar Spinal Canal Stenosis.

Experimental study. We sought to elucidate the association between ligamentum flavum thickening and tissue buckling, and the clinical and imaging factors related to buckling by comparing the ligamentum flavum thickness on MRI images and within the actual tissue. Ligamentum flavum thickening is a main contributor to lumbar spinal canal stenosis. Buckling of the tissue may contribute to ligamentum flavum thickening along with tissue hypertrophy; however, this association has not been established conclusively. Ligamentum flavum samples (135 ligament samples) from 70 patients with lumbar spinal canal stenosis were evaluated. The ligamentum flavum thicknesses on magnetic resonance imaging (MRI) and in the tissue samples were compared to assess for the presence of buckling. The ligamentum flavum samples were divided into groups with or without buckling based on the difference between their thicknesses on MRI and in the tissues. The Pearson correlation coefficient test was used to assess the relationships between the LF thicknesses on MRI and in the tissues, MRI-tissue difference and LF thickness in the tissues, and MRI-tissue difference and LF thickness on MRI. Further, differences between the buckling+ and buckling- groups were compared using the unpaired t-test (LF thickness on MRI, LF thickness in the tissues, age, disc angle, and disc height) and χ2 (disc level, disc degeneration, and receival/nonreceival of dialysis) test. The ligamentum flavum thickness on MRI and in the tissues had a positive linear relationship, although the thickness was estimated to be significantly larger on MRI than in the tissues themselves. The ligamentum flavum with buckling had a larger thickness on MRI, less tissue hypertrophy, more severe disc degeneration, and was present in patients with a higher rate of dialysis. There were no differences in age and disc height, angle, or level between the two groups. Buckling of the ligamentum flavum coexists with tissue hypertrophy and contributes to perceived ligamentum thickening on imaging. Buckling of the ligamentum flavum tends to occur in less hypertrophied tissues and is associated with the grade of disc degeneration and the presence of other characteristics associated with spinal degeneration.

Interpretable Machine Learning Models Based on SHapley Additive exPlanations for Predicting the Risk of Cerebrospinal Fluid Leakage in Lumbar Fusion Surgery.

Retrospective study. The objective of this investigation was to formulate and internally verify a customized machine learning (ML) framework for forecasting cerebrospinal fluid leakage (CSFL) in lumbar fusion surgery. This was accomplished by integrating imaging parameters and employing the SHapley Additive exPlanation (SHAP) technique to elucidate the interpretability of the model. Given the increasing incidence and surgical volume of spinal degeneration worldwide, accurate predictions of postoperative complications are urgently needed. SHAP-based interpretable ML models have not been used for CSFL risk factor analysis in lumbar fusion surgery. Clinical and imaging data were retrospectively collected from 3505 patients who underwent lumbar fusion surgery. Six distinct machine learning models were formulated: extreme gradient boosting (XGBoost), decision tree (DT), random forest (RF), support vector machine (SVM), Gaussian naive Bayes (GaussianNB), and K-nearest neighbors (KNN) models. Evaluation of model performance on the test dataset was performed using performance metrics, and the analysis was executed through the SHAP framework. CSFL was detected in 95 out of 3505 patients (2.71%). Notably, the XGBoost model exhibited outstanding accuracy in forecasting CSFLs, with high precision (0.9815), recall (0.6667), accuracy (0.8182), F1 score (0.7347), and AUC (0.7343). Additionally, through SHAP analysis, significant predictors of CSFL were identified, including ligamentum flavum thickness, zygapophysial joint degeneration grade, central spinal stenosis grade, decompression segment count, decompression mode, intervertebral height difference, Cobb angle, intervertebral height index difference, operation mode, lumbar segment lordosis angle difference, Meyerding grade of lumbar spondylolisthesis, and revision surgery. The combination of the XGBoost model with the SHAP is an effective tool for predicting the risk of CSFL during lumbar fusion surgery. Its implementation could aid clinicians in making informed decisions, potentially enhancing patient outcomes and lowering healthcare expenses. This study advocates for the adoption of this approach in clinical settings to enhance the evaluation of CSFL risk among patients undergoing lumbar fusion.

Is there a relationship between low back pain and ligamentum flavum hypertrophy?

A condition known as ligamentum flavum (LF) hypertrophy occurs when the ligamentum flavum (LF) swells as a result of pressures applied to the spine. Among the elderly population, lumbar spinal stenosis is a major cause of pain and disabilities. Numerous studies indicate that lumbar spinal stenosis etiology involves the ligamentum flavum in a major way. This study looks into the relationship between low back pain and ligamentum flavum thickening. The imaging tests and case histories of all patients with low back pain who had consecutive magnetic resonance imaging exams performed at the Prince Sattam University and King Khalid hospitals in Al Kharj City will serve as the basis for this retrospective observational study. A radiologist utilized the Pfirrmann grading system, which is based on spinal levels starting from the first lumbar to the first sacral vertebrae, to measure the thickness of the ligamentum flavum in all cases who underwent magnetic resonance imaging (MRI). A correlation between age, hypertrophy of LF, and low back pain was investigated. There were 79 participants in the study, ages ranging from 21 to 82, 49 of which were men. The patients' average age was 54 years, and 62% of them were men. We found no appreciable variations in LF thickness according to gender. At the L4-L5 and L5-S1 levels, the left LF was noticeably thicker than the right. Moreover, there was a significant difference (p < 0.05) in the bilateral LF thicknesses at L5-S1 compared to the comparable sides at L4-L5. By evaluating the thickness of LF on magnetic resonance images, we discovered that it may be closely associated with the etiology of pain processes in the spine.

MRI parameters predict central lumbar spinal stenosis combined with redundant nerve roots: a prospective MRI study.

To observe changes in the cauda equina nerve on lumbar MRI in patients with central lumbar spinal stenosis (LSS). 878 patients diagnosed with LSS by clinical and MRI were divided into the redundant group (204 patients) and the nonredundant group (674 patients) according to the presence or absence of redundant nerve roots (RNRs). The anteroposterior diameter of the spinal canal (APDS) and the presence of multiple level stenosis, disc herniation, thickening of ligamentum flavum (LF) and increased epidural fat were assessed on MRI. Univariate and multivariate logistic regression analyses were performed to explore the predictors of LSS combined with RNRs. Patients with LSS combined with RNRs had thicker epidural fat, smaller APDS and more combined multifaceted stenosis. Female patients and older LSS patients were more likely to develop RNRs; there was no difference between two groups in terms of disc herniation (p > 0. 05). Age, APDS, multiple level stenosis, and increased epidural fat were significantly correlated with the formation of LSS combined with RNRs (p < 0.05). A smaller APDS and the presence of multiple level stenosis, thickening of LF, and increased epidural fat may be manifestations of anatomical differences in patients with LSS combined with RNRs. Age, APDS, multiple level stenosis, and increased epidural fat play important roles. The lumbar spine was measured and its anatomy was observed using multiple methods, and cauda equina changes were assessed to identify the best anatomical predictors and provide new therapeutic strategies for the management of LSS combined with RNRs.

Evaluation of the Thickness of Ligamentum Flavum at the Level of Lumbosacral Spine (L4-L5, L5-S1) and its Relationship with Degenerative Disc Changes in Patients Undergoing MRI of Lumbosacral Spine

Introduction: Low back pain (LBP) is a very common cause of disability in working-age adults; with degenerative changes being the predominant cause apart from anatomical factors. Degenerative changes in the lumbar spine are associated with the alteration of the thickness of the Ligamentum Flavum (LF), which predisposes to clinical symptoms. Methods: This was a prospective study conducted among ninety symptomatic (LBP) patients who underwent magnetic resonance imaging (MRI) and the images were evaluated to measure the thickness of the LF and evaluate the degree of disc degeneration by the Pfirrmann grading system, according to the spinal levels (L4-L5, L5-S1). An association was sought between LF hypertrophy and disc degeneration, age, sex, and disc height. Results: The result of this study showed that with increasing age thickening of the LF could lead to degeneration of the intervertebral disc. Thickening of the LF was more at the level of L4-L5 level than at the L5-S1 level with right-sided increased thickness more than on the left and is associated with increased grade of disc degeneration. Females had slightly more thickened LF than the males at the L4-L5 level with no gender predominance at the L5-S1 level. Conclusions: Thickening of the ligamentum flavum may be an important factor in the origin of LBP, especially in the adult population. A degenerative process in the ligamentum flavum that occurs with age and also suggests the thickening of LF due to mechanical stress at the lumbar level would ultimately result in degeneration of the disc.

MiR-29b-3p Affects the Hypertrophy of Ligamentum Flavum in Lumbar Spinal Stenosis and its Mechanism.

To explore the effect of miR-29b-3p on fibrosis and hypertrophy of ligamentum flavum (LF) in lumbar spinal stenosis (LSS) and its underlying mechanism. Patients with LSS and lumbar disc herniation (LDH) (control) undergoing posterior lumbar laminectomy were included in this study. Human LF samples were obtained for LF cell isolation, RNA, and protein extraction. Histomorphological analysis of LF was performed using hematoxylin-eosin (HE) staining. After isolation, culture, and transfection of primary LF cells, different transfection groups were constructed: NC-mimic, miR-29b-3p-mimic, NC-inhibitor, and miR-29b-3p-inhibitor. Quantitative real time polymerase chain reaction (qRT-PCR) was performed to detect the expression of miR-29b-3p in LF and LF cells. Western blot analysis detected the protein expressions of P16 and CyclinD1. ELISA detected the protein expressions of TGF-β1, Smad2, Smad3, TLR4, Type I collagen, and Type III collagen. Finally, LF cell viability was detected using the Cell Counting Kit-8 (CCK8) assay. The thickness of LF was significantly thicker in the LSS group compared to the LDH group (p < 0.05), accompanied by a higher calcification degree, more fibroblasts, and a larger area of collagen fiber proliferation. miR-29b-3p expression was significantly lower in LSS-derived LF tissues and cells than in LDH-derived tissues and cells (both p < 0.05). Compared to the NC-mimic group, the miR-29b-3p-mimic group exhibited significantly higher miR-29b-3p expression, decreased protein expressions of Type I collagen, Type III collagen, TGF-β1, Smad2, Smad3, TLR4, P16, and CyclinD1, and inhibited LF cell proliferation (all p < 0.05). As expected, the miR-29b-3p-inhibitor group displayed contrasting expression patterns (all p < 0.05). Compared to the phosphate buffer saline (PBS) group, the Trimethylamine-N-Oxide (TMAO) group showed significantly increased expressions of TGF-β1, Smad2, Smad3, TLR4, Type I collagen, Type III collagen, P16, and CyclinD1, as well as enhanced LF cell proliferation (all p < 0.05). However, there was no significant difference between the TMAO group and the Ang II group (all p > 0.05). Upregulation of miR-29b-3p expression may play a role in improving LF fibrosis and hypertrophy in LSS by inhibiting P16 expression and suppressing the activation of the TGF-β/Smad signaling pathway. This finding offers new insights into future gene modification therapy for this patient population.

Anatomic, Image-based Classification of Diseased Lumbar Spinal Motion-Segment-Preliminary Clinical Report

Background: Multiple minimally invasive spine approaches and techniques have been developed in recent years. While the disease processes affecting the spinal motion-segment (SMS) have remained largely the same, surgical treatment options have changed radically and not necessarily in an organized fashion. This is inevitable given the rapid evolution of the technology. The current image-based diagnostic techniques, also evolving, have helped us appreciate the disease Patho anatomy in minute detail. A comprehensive classification method accounting for all anatomical participants in the spinal motion-segment pathology, tailored to treatment options, is necessary. Out of the many valid options, a spine surgeon should be able to choose a single surgical approach that is most appropriate for the Patho anatomy of his/her patient’s disease. We feel that our classification system will help the spine surgeon make that important decision consistently, with minimal risk of leaving behind a significant lesion, or disrupting a structure which is not a participant in the disease process. Furthermore, universal acceptance of this classification system will make it easier for spine surgeons to communicate with each other and meaningfully compare the results of the various surgical approaches. Purpose of the Study: To develop a comprehensive, treatment-orientated classification of lumbar spinal motion-segment disease. Materials and Methods: Contributors to spinal motion-segment disease - intervertebral disc, facet joint, ligamentum flavum and mal-alignment were identified. The degrees of abnormalities in each of these entities were coded, and the codes were entered in a table from which the possible combinations of pathologic processes were generated. Study of 57 lumbar MRI images (217 spinal motion-segments) was carried out to determine the prevalence of various combinations of the motion-segment disease. Pre- and post-operative MRI-based spinal motion-segment classifications were performed to evaluate the clinical application of this classification system in 15 patients. Results: This classification presents 494 possible combinations of the spinal motion-segment disease. Many of the combinations are only theoretical possibilities without clinical significance. Normal motion-segments, D0 A0 L0 F0 , represented 33.3% of the total motion-segments; D1 A0 L0 F0 was 8.8%, representing bulging disc, normal alignment, ligamentum flavum and facet joint. D2 A0 L0 F2 was 6.9% representing intraannular disc herniation, normal alignment, mildly thickened ligamentum flavum, and hypertrophied superior articular process of the facet joint. 6.4% was D1 A0 L1 F3 representing bulging disc, mildly hypertrophic ligamentum and hypertrophied facet joint. Clinical application of the classification revealed: Accurate anatomic classification; immediate post-operative classification changes which correlate with patient’s symptoms; pre-operative, immediate post-operative and late post-operative classifications which correlate with patient’s symptoms and accurately demonstrate post-operative remodeling of the motion-segment, especially after disc surgery, and accurate; and anatomic documentation of pre- and post op classifications of interlaminar endoscopic decompression. Conclusion: A treatment-orientated, standardized classification of spinal motion-segment disease is necessary considering current multiple treatment options and availability of sophisticated pre-operative imaging techniques. Such a classification will allow standardization of treatment options for various combinations of the pathological processes. With the emergence of new technologies surgical options can be upgraded based on a standardized classification. This in turn will help minimize confusion for those who want to learn and facilitate growth in the minimally invasive technology. The preliminary results of clinical application of the classification showed it to be a very accurate patho-anatomic representation; immediate post-operative classification change reflected clinical improvement post-operatively; and precise representation of post-operative remodeling of the motion-segment one to two years post-operatively. The precision of this classification allows accurate communication regarding the pathology, between providers across the globe, and more accurate comparison of results of different surgical interventions.

Increased matrix metalloproteinase-2 in ligamentum flavum hypertrophy and the regulation of MMP-2/TIMPs by elastin-derived peptides.

The study aimed to examine matrix metalloproteinase-2 (MMP-2) expression in a rat ligamentum flavum (LF) hypertrophy model in vivo, and the effect of elastin-derived peptides (EDPs) on MMP-2 and tissue inhibitors of metalloproteinases (TIMPs) in rat LF cells in vitro. Surgical destabilization was performed at the rat spinal L3/4 level to induce increased mechanical stress. Rats were killed at 6- and 12-weeks postsurgery for histological staining, immunohistochemical staining, RT-qPCR and western blot. 100 µg/mL EDPs were applied to isolated normal rat LF cells, with or without pretreatment of elastin receptor complex (ERC) inhibitors, to assess the expression of MMP-2, TIMP-1, and TIMP-2. Spinal destabilization led to LF hypertrophy, observed through increased LF thickness and area, along with histological changes of chondrometaplasia and elastic fiber degradation. LF was also stained positively for Col I and Col II, where elastic fiber has broken down. MMP-2 expression was notably elevated in the hypertrophied LF, accompanied by increased TIMP-2 and TIMP-3 levels. EDPs were found to suppress MMP-2 expression and reduce TIMP-1 and TIMP-2 levels in rat LF cells. Interestingly, exposure to EDPs led to a significant rise in MMP-2/TIMP-1 and MMP-2/TIMP-2 ratios, dependent on the ERC. Collectively, the study suggests that increased MMP-2 activity contributes to elastic fiber degradation in hypertrophied LF, generating EDPs that further enhance the MMP-2/TIMPs ratio in LF cells in an ERC-dependent manner. Further research is essential to delve into the mechanisms of EDPs in LF hypertrophy.

Comparative Gene-Expression Analysis of the Ligamentum Flavum of Patients with Lumbar Spinal Canal Stenosis: Comparison between the Dural and Dorsal Sides of the Thickened Ligamentum Flavum.

Thickening of the ligamentum flavum is the main factor in the development of lumbar spinal canal stenosis (LSCS). Although previous studies have reported factors related to ligamentum flavum thickening, its etiology has not been clarified. Furthermore, it is often difficult to set proper controls to investigate the pathologies of thickening due to differences in patient characteristics, such as age, sex, obesity, and comorbidities. This study aimed to elucidate the pathologies of ligamentum flavum thickening by comparing the dural and dorsal sides of the thickened ligamentum flavum in patients with LSCS. Ligamentum flavum samples were collected from 19 patients with LSCS. The samples were divided into the dural and dorsal sides. The dural side was used as a control to assess the pathologies occurring on the dorsal side. Elastic Masson staining was used to assess the elastic fibres. Gene expression levels were comprehensively assessed using quantitative reverse transcription polymerase chain reaction and DNA microarray analyses. Gene ontology analysis was used to identify biological processes associated with differentially expressed genes. The elastic fibres were significantly decreased on the dorsal side of the thickened ligamentum flavum. Genes related to fibrosis, inflammation, tissue repair, remodeling, and chondrometaplasia, such as COL1A2, COL3A1, COL5A1, TGFB1, VEGFA, TNFA, MMP2, COL10A1, and ADAMTS4, were highly expressed on the dorsal side of the thickened ligamentum flavum. The biological processes occurring on the dorsal side of the thickened ligamentum flavum were extracellular matrix organization, cell adhesion, extracellular matrix disassembly, and proteolysis.These are considered important pathologies of ligamentum flavum thickening.

The Symptomatic Calcification and Ossification of the Ligamentum Flavum in the Spine: Our Experience and Review of the Literature.

We report our experience regarding the clinical features and pathological findings of the calcification of the ligamentum flavum (CLF) and ossification of the ligamentum flavum (OLF) in the spine. In addition, we reviewed the previous studies on CLF and OLF to enhance the understanding of these conditions. We compared the clinical, radiological, and histopathological features of CLF and OLF. In CLF, a computed tomography (CT) scan showed egg-shaped or speck-like calcification in the ligamentum flavum. Magnetic resonance (MR) imaging demonstrated spinal cord compression due to a thickened ligamentum flavum, which appeared as a low-intensity mass. Pathological findings demonstrated fused islands of calcification resembling sand-like calcification. In OLF, CT showed beak-like ossification extending into the intervertebral foramen. MR imaging demonstrated spinal cord compression by a low-intensity mass. Pathological findings revealed laminar ossification of LF with chondrocytes near the calcification and laminar hyaline cartilage. CLF and OLF appear to be distinct entities based on their clinical, neuroradiological, histopathological, and pathogenetic features. We suggest that the causes of CLF include both metabolic and dystrophic factors, while the pathogenesis of OLF is characterized by enchondral ossification induced by a genetic cascade triggered by shearing/tension stress.

The cervical ligamentum flavum area: A new sensitive morphological parameter for identifying the cervical spinal stenosis.

Thickening of the cervical ligamentum flavum (CLF) has been considered as a main cause of cervical spinal stenosis (CSS). A previous study reported that cervical ligamentum flavum thickness (CLFT) is correlated with CSS. However, the whole hypertrophy is different from focal thickness. Therefore, to analyze hypertrophy of the CLF, we created a new morphological parameter, called the cervical ligamentum flavum area (CLFA). We hypothesized that the CLFA is an important morphological parameter in the diagnosis of CSS. CLF samples were acquired from 83 patients with CSS, and from 84 controls who underwent cervical magnetic resonance imaging (C-MRI). T2-weighted axial C-MRI images were acquired. We measured the CLFA and CLFT at the C6-C7 intervertebral level on C-MRI using appropriate image analysis software. The CLFA was measured as the cross-sectional area of the entire CLF at the level of C6-C7 stenosis. The CLFT was measured by drawing a straight line along the ligament side towards the spinal canal at the C6-C7 level. Mean CLFA was 25.24 ± 6.43 mm2 in the control group and 45.34 ± 9.09 mm2 in the CSS group. The average CLFT was 1.48 ± 0.28 mm in the control group and 2.09 ± 0.35 mm in the CSS group. CSS patients had significantly higher CLFA (P < .01) and CLFT (P < .01). For the validity of both CLFA and CLFT as predictors of CSS, a receiver operating characteristic curve analysis revealed an optimal cutoff point for the CLFA was 31.66 mm2, a sensitivity of 92.8%, specificity of 88.4%, and an area under the curve of 0.97 (95% CI, 0.94-0.99). The optimal cut off-point of the CLFT was 1.79 mm, with a sensitivity of 83.5%, specificity of 84.5%, and an area under the curve of 0.92 (95% CI, 0.87-0.96). Both CLFT and CLFA were significantly related to CSS, but CLFA was the more sensitive measurement parameter. Therefore, to evaluate patients with CSS, treating physicians should test for CLFA.

The biomechanical effect of different types of ossification of the ligamentum flavum on the spinal cord during cervical dynamic activities

Ossification of the ligamentum flavum (OLF) is thought to be an influential etiology of myelopathy, as thickened ligamentum flavum causes the stenosis of the vertebral canal, which could subsequently compress the spinal cord. Unfortunately, there was little information available on the effects of cervical OLF on spinal cord compression, such as the relationship between the progression of cervical OLF and nervous system symptoms during dynamic cervical spine activities. In this research, a finite element model of C1-C7 including the spinal cord featured by dynamic fluid-structure interaction was reconstructed and utilized to analyze how different types of cervical OLF affect principal strain and stress distribution in spinal cord during spinal activities towards six directions. For patients with cervical OLF, cervical extension induces higher stress within the spinal cord among all directions. From the perspective of biomechanics, extension leads to stress concentration in the lateral corticospinal tracts or the posterior of gray matter. Low energy damage to the spinal cord would be caused by the high and fluctuating stresses during cervical movements to the affected side for patients with unilateral OLF at lower grades.

The correlation between clinical symptom and morphological parameters on magnetic resonance imaging in patients with spondylolisthesis levels L4/L5 and L5/S1.

Spondylolisthesis is one of the common causes of spinal pain. There is currently a lack of studies on the correlation between magnetic resonance imaging (MRI) and clinical symptoms of patients with spondylolisthesis. This study is aimed to find the correlation between clinical symptoms of L4/L5, L5/S1 lumbar spondylolisthesis, and imaging parameters on MRI. A retrospective study on 100 patients who were diagnosed with lumbar spondylolisthesis at the L4/L5, L5/S1 levels from August 2022 to February 2023. Parameters on MRI are measured the cross-sectional area of the dural sac (DSA), the cross-sectional area of the spinal canal (SCA), the ligamentum flavum cross-sectional area (LFA), and ligamentum flavum thickness (LFT), anterior-posterior diameter (APD), sliding distance (SD) at the spondylolisthesis level. Clinical symptoms were investigated according to the Visual Analogue Scale (VAS) for grading of pain and the subjective disability was assessed by the Oswestry Disability Index (ODI). There was no statistically significant difference between SD, APD, SCA, DSA, LFA, and LFT between the mild and moderate pain VAS and severe pain VAS groups. No correlation was found between VAS and SD, APD, SCA, DSA, LFA, and LFT. There is a negative correlation between ODI and APD, SCA, and DSA. The statistically significant difference in APD, SCA, and DSA indexes in the two groups with mild/moderate disability (ODI ≤40%) and the group with severe disability (ODI >40%). A higher DSA and SCA, APD are associated with lower ODI. Decreased APD, SCA, and DSA are all suggestive of decreased spinal function. However, the MRI findings did not correlate with the patient's clinical pain level.

Pre-operative magnetic resonance imaging as a predictor of success in lumbar disc herniation patients undergoing laminectomy

Introduction. Lumbar disc herniation is a condition in which annulus fibrosus in the lumbar area is herniated with numerous etiologies, such as degenerative. One of the mainstay treatment for lumbar disc herniation is decompressive laminectomy. Magnetic Resonance Imaging (MRI) with the diagnostic accuracy of 97% also has an excellent resolution for soft tissue. The aim of this study is whether pre-operative MRI may be a predictor of successful clinical outcome in lumbar disc herniation patients undergoing laminectomy surgery. Methods. In this cross-sectional study, we consecutively collected all patients in Radiology Department “Prof. Dr. IGNG Ngoerah” Hospital, Denpasar Bali between January 2021 to December 2022. We enrolled patients with older than 18 years old who had undergone pre-operative lumbosacral MRI and had laminectomy surgery within the sampling time period. The following variables were recorded from each patient: age, gender, Body mass index (BMI), history of diabetes mellitus, hypertension, number of herniated discs, herniation grade, spinal canal stenosis grade, neural foramen stenosis grade, lateral recess stenosis grade, annular tear, disc degeneration, facet disc degeneration, thickening of ligamentum flavum, modic changes, cerebrospinal liquor obstruction, and clinical outcome. Outcomes. We collected 30 patients who underwent laminectomy surgery and had their pre-operative MRI. Patients’ mean age ± SD was 57.7±10.9 years old with 20 male (66.7%) and 10 female (33.3%). There was no significant association between gender, hypertension, diabetes mellitus, body mass index, number of disc herniation, spinal canal stenosis, lateral recess stenosis, neural foramen stenosis, disc degeneration, facet joint degeneration, ligamentum flavum hypertrophy, Modic changes and cerebrospinal liquor obstruction with clinical outcome post laminectomy patients. Conclusion. Pre-operative MRI can reliably diagnose lumbar disc herniation but are not a predictive tool in assessing the clinical outcome of post-laminectomy patients. Laminectomy has an excellent management value for lumbar disc herniation patients especially in reducing the pain, and for them to have better quality of life.

Comparison of ligamentum flavum thickness between central and lateral lesions in a patient with central lumbar spinal canal stenosis.

Thickened ligamentum flavum has been considered as a major cause of central lumbar spinal canal stenosis (CLSCS). Previous studies have demonstrated that ligamentum flavum thickness (LFT) is correlated with aging, degenerative spinal stenosis, and disc degeneration. Thus, hypertrophy of the ligamentum flavum is a major cause of CLSCS, and measurement of LFT has been considered a morphologic parameter in the diagnosis of CLSCS. To our knowledge, comparison of LFT between central and lateral lesions has not been reported. In addition, no research has analyzed best clinical cutoff values of central ligament flavum thickness (CLFT) and lateral ligament flavum thickness (LLFT). This study aimed to compare CLFT with LLFT in patients with CLSCS and further compare the CLFT and LLFT findings between the 2 groups to analyze LFT variation. Both CLFT and LLFT samples were collected from 101 participants with CLSCS and from 103 participants in the control group who underwent lumbar magnetic resonance imaging without evidence of CLSCS. Axial T2-weighted lumbar magnetic resonance scans were acquired at the L4 to 5 facet joint level from each participant. Average CLFT value was 2.25 ± 0.51 mm in the control group and 4.02 ± 0.74 mm in the CLSCS group. Average LLFT value was 2.50 ± 0.51 mm in the control group and 3.38 ± 0.66 mm in the CLSCS group. CLSCS patients had significantly higher CLFT and LLFT (both P < .001). Regarding the validity of both CLFT and LLFT as predictors of CLSCS, a receiver operating characteristic estimation revealed that the most suitable cutoff value for CLFT was 3.10 mm, with sensitivity of 95.0%, specificity of 94.2%, and an area under the curve of 0.97. The best cut-off value of LLFT was 2.92 mm, with sensitivity of 78.2%, specificity of 77.7%, and area under the curve of 0.87. We have 4 important new findings: The mean CLFT is significantly lower than that of the mean LLFT in the normal control group; CLFT and LLFT are both significantly associated with CLSCS; Increase rate of CLFT is faster than that of LLFT in the CLSCS group; and CLFT is a more sensitive measurement parameter to predict CLSCS than LLFT.

Prevalence of amyloid in ligamentum flavum of patients with lumbar spinal stenosis

Background Transthyretin (ATTR) amyloidosis is often diagnosed in an advanced stage, when irreversible cardiac damage has occurred. Lumbar spinal stenosis (LSS) may precede cardiac ATTR amyloidosis by many years, offering the opportunity to detect ATTR already at the time of LSS surgery. We prospectively assessed the prevalence of ATTR in the ligamentum flavum by tissue biopsy in patients aged >50 years undergoing surgery for LSS. Methods Ligamentum flavum thickness was assessed pre-operatively on axial T2 magnetic resonance imaging (MRI) slices. Tissue samples from ligamentum flavum were screened centrally by Congo red staining and immunohistochemistry (IHC). Results Amyloid in the ligamentum flavum was detected in 74/94 patients (78.7%). IHC revealed ATTR in 61 (64.9%), whereas amyloid subtyping was inconclusive in 13 (13.8%). Mean thickness of ligamentum flavum was significantly higher at all levels in patients with amyloid (p < .05). Patients with amyloid deposits were older (73.1 ± 9.2 vs. 64.6 ± 10.1 years, p = .01). No differences in sex, comorbidities, previous surgery for carpal tunnel syndrome or LSS were observed. Conclusions Amyloid, mostly of the ATTR subtype, was found in four out of five patients with LSS and is associated with age and ligamentum flavum thickness. Histopathological work-up of ligamentum flavum might inform future decision making.

Correlation of the Risk Factors in Degenerative Lumbar Spondylolisthesis with MRI Imaging

Introduction: Degenerative spondylolisthesis burdens the future economy. Elderly individuals with this condition suffer from back pain, limb paralysis, reduced activity, and diminished quality of life. Surgery offers relief but is risky and expensive. As healthcare improves, the aging population grows, and spondylolisthesis incidence rises. Early detection and risk factor management are vital for prevention. Therefore, this study aimed to evaluate the correlation of the risk factors for degenerative lumbar spondylolisthesis. Methods: A retrospective observational study was done in Dr Soetomo General Academic Hospital, Surabaya from January 2018 to December 2019. Forty-five subjects with degenerative spondylolisthesis diagnosed by MR Imaging enrolled in this study. Intervertebral disc, facet joint, multifidus muscle, and ligamentum flavum at level L1 until level L5 were examined using MR imaging. Correlation analysis was measured using the Spearman correlation test and risk factor analysis was measured using the logistic regression test. Results: There are significant correlations between intervertebral disc degeneration, facet joint osteoarthritis, multifidus muscle fatty infiltration, and thickening of ligamentum flavum with degenerative spondylolisthesis. The risk factors at levels L3-4 and L5-S1 are intervertebral disc degeneration and L4-5 is multifidus muscle fatty infiltration and facet joint osteoarthritis. Conclusion: This study confirmed the risk factors that correlated with degenerative lumbar spondylolisthesis.

GSK-3β and β-Catenin Signaling Pathway is Involved in Myofibroblast Transition of Ligamentum Flavum in Lumbar Spinal Stenosis Patients.

Histologic analysis of the ligamentum flavum (LF) in the lumbar spine. The objective of this study is to investigate the levels of glycogen synthase kinase-3β (GSK-3β) and β-catenin in the LF tissue of patients with lumbar spinal stenosis (LSS). The hypertrophy of the LF is the primary cause of the progression of LSS. Recently, Wnt signaling has been proposed as one of the molecular processes contributing to LF hypertrophy. GSK-3β and β-catenin are recognized to play a crucial part in the control of this signaling pathway. From May 2020 to July 2022, LF from 51 LSS patients (LSS group) and 18 lumbar disc herniation patients (control group) were prospectively collected during surgery. Histologic analysis was investigated to confirm the progression of LF fibrosis. The levels of α-smooth muscle actin, phosphorylation of GSK-3β (p-GSK-3β; inactive form), and β-catenin were analyzed in LF with Western blot analysis to reveal the GSK-3β/β-catenin signaling pathway. Continuous variables are expressed as mean±SD and compared using the student t test. Categorical variables are compared using the χ 2 test or Fisher exact test, as appropriate. To determine the association between p-GSK-3β and LF thickness, the Pearson correlation coefficient was calculated based on the results of Western blot analysis. The LSS group was older and had thicker LF than the controls. The LSS group showed increased collagen fiber and cellularity than the controls. The levels of α-smooth muscle actin, p-GSK-3β, and β-catenin in the LF of the LSS group were significantly higher than that of the control group. There was a strong positive correlation between p-GSK-3β (Ser9) level and LF thickness in LSS patients ( r =0.69, P =0.01). This research proposes a molecular mechanism for the pathogenesis of LF hypertrophy in LSS. Specifically, GSK-3β/β-catenin signaling appears to be related to LF hypertrophy in LSS and a positive correlation exists between p-GSK-3β level and LF thickness. Level 3.