Vertebral Bone Research Articles

Single-cell RNA landscape of osteoimmune microenvironment in osteoporotic vertebral compression fracture and Kümmell's disease.

Background: Single-cell RNA sequencing (scRNA-seq) enables specific analysis of cell populations at single-cell resolution; however, there is still a lack of single-cell-level studies to characterize the dynamic and complex interactions between osteoporotic vertebral compression fractures (OVCFs) and Kümmell's disease (KD) in the osteoimmune microenvironment. In this study, we used scRNA-seq analysis to investigate the osteoimmune microenvironment and cellular composition in OVCFs and KD. Methods: ScRNA-seq was used to perform analysis of fractured vertebral bone tissues from one OVCF and one KD patients, and a total of 8,741 single cells were captured for single-cell transcriptomic analysis. The cellularity of human vertebral bone tissue was further analyzed using uniform manifold approximation and projection. Pseudo-time analysis and gene enrichment analysis revealed the biological function of cell fate and its counterparts. CellphoneDB was used to identify the interactions between bone cells and immune cells in the osteoimmune microenvironment of human vertebral bone tissue and their potential functions. Results: A cellular profile of the osteoimmune microenvironment of human vertebral bone tissue was established, including mesenchymal stem cells (MSCs), pericytes, myofibroblasts, fibroblasts, chondrocytes, endothelial cells (ECs), granulocytes, monocytes, T cells, B cells, plasma cells, mast cells, and early erythrocytes. MSCs play an immunoregulatory function and mediate osteogenic differentiation and cell proliferation. The differentiation trajectory of osteoclasts in human vertebral bone tissue was also revealed. In addition, ECs actively participate in inflammatory infiltration and coupling with bone cells. T and B cells actively participate in regulating bone homeostasis. Finally, by identifying the interaction of ligand-receptor pairs, we found that immune cells and osteoclasts have bidirectional regulatory characteristics, have the effects of regulating bone resorption by osteoclasts and promoting bone formation, and are essential for bone homeostasis. It is also highlighted that CD8-TEM cells and osteoclasts might crosstalk via CD160-TNFRSF14 ligand-receptor interaction. Conclusion: Our analysis reveals a differential landscape of molecular pathways, population composition, and cell-cell interactions during OVCF development into KD. OVCFs exhibit a higher osteogenic differentiation capacity, owing to abundant immune cells. Conversely, KD results in greater bone resorption than bone formation due to depletion of MSCs and a relatively suppressed immune system, and this immune imbalance eventually leads to vertebral avascular necrosis. The site of action between immune cells and osteoclasts is expected to be a new therapeutic target, and these results may accelerate mechanistic and functional studies of osteoimmune cell types and specific gene action in vertebral avascular necrosis and pathological bone loss diseases, paving the way for drug discovery.

Clinical and radiological outcomes of n-HA/PA66 cages in anterior spine reconstruction following total en bloc spondylectomy for tumors.

This retrospective monocentric study was conducted to evaluate the clinical and radiological outcomes of the nano-hydroxyapatite/polyamide66 (n-HA/PA66) cage in reconstructing the anterior column of the spine following total en bloc spondylectomy (TES). A cohort of 24 patients, 20 diagnosed with primary malignant tumors and 4 with metastatic malignancies, was selected based on specific inclusion criteria. All were subjected to TES and anterior column reconstruction with the n-HA/PA66 cage from January 2013 to July 2023 at a single institution. Pre-operative embolization was performed on all patients. Documented factors included operation duration, intraoperative blood loss, length of hospital stay, treatment history, and involved level. Mechanical complications and radiological parameters such as the local kyphotic angle (LKA), anterior vertebral height (AVH), posterior vertebral height (PVH), cage subsidence, and bone fusion time were evaluated. Quality of life and neurological function were gauged using tools like the Visual Analog Scale (VAS), Eastern Cooperative Oncology Group (ECOG) performance score, Karnofsky Performance Score (KPS) scale, and American Spinal Injury Association (ASIA) grading. All patients were followed up for 12-127 months, with an average period of 39.71 months. An average operation time of approximately 8.57 h and a blood loss volume of about 1,384 ml were recorded. No instances of tumor recurrence or multiple organ metastases were reported, though recurrence was detected in 2 living patients. Solid fusion was achieved in all patients at a mean time of 6.76 ± 0.69 months. Cage breakage or migration was not observed. Subsidence into the adjacent vertebral bodies was identified in 3 patients but was deemed clinically irrelevant. Significant improvements in VAS, ECOG performance score, KPS scale, and ASIA scores were noted from pre- to post-surgery (P < 0.05). A marked enhancement in the AVH was observed from before surgery to immediately after (P < 0.05). LKA, AVH, and PVH values between postoperative and final follow-up showed no significant variance (P > 0.05). The integration of TES and the n-HA/PA66 cage was found to yield promising clinical and radiological outcomes in anterior column spine reconstruction. The use of this material did not hinder oncological care, including the provision of adjuvant treatments (chemo/radiotherapy), ultimately contributing to the enhanced long-term quality of life for spinal tumor patients.

Low-Density Lipoprotein Cholesterol and Statin Usage Are Associated With Rates of Pseudarthrosis Following Single-Level Posterior Lumbar Interbody Fusion.

Retrospective cohort study. To investigate the relationships of low-density lipoprotein cholesterol and statin usage with pseudarthrosis following single-level posterior or transforaminal lumbar interbody fusion (PLIF/TLIF). Hypercholesterolemia can lead to atherosclerosis of the segmental arteries, which branch into vertebral bone through intervertebral foramina. According to the vascular hypothesis of disc disease, this can lead to ischemia of the lumbar discs and contribute to lumbar degenerative disease. Yet, little has been reported regarding the effects of cholesterol and statins on the outcomes of lumbar fusion surgery. TriNetX, a global federated research network, was retrospectively queried to identify 52,140 PLIF/TLIF patients between 2002 and 2021. Of these patients, 2137 had high cholesterol (≥130mg/dL) and 906 had low cholesterol (≤55 mg/dL). Perioperatively, 18,275 patients used statins, while 33,415 patients did not. One-to-one propensity score matching for age, sex, race, and comorbidities was conducted to balance the analyzed cohorts. The incidence of pseudarthrosis was then assessed in the matched cohorts within the six-month, one-year, and two-year postoperative periods. After propensity score matching, high-cholesterol patients had greater odds of developing pseudarthrosis six months [odds ratio (OR): 1.73, 95% confidence interval (CI): 1.28-2.33], one year (OR: 1.59, 95% confidence interval (CI): 1.20-2.10), and two years (OR: 1.57, 95% CI: 1.20-2.05) following a PLIF/TLIF procedure. Patients with statin usage had significantly lower odds of developing pseudarthrosis six months (OR: 0.74, 95% CI: 0.69-0.79), one year (OR: 0.76, 95% CI: 0.71-0.81), and two years (OR: 0.77, 95% CI: 0.72-0.81) following single-level PLIF/TLIF. The findings suggest that patients with hypercholesterolemia have an increased risk of developing pseudarthrosis following PLIF/TLIF while statin use is associated with a decreased risk. The data presented may underscore an overlooked opportunity for perioperative optimization in lumbar fusion patients, warranting further investigation in this area.

An Integrated Approach for Designing and Analyzing Lumbar Vertebral Biomodels with Artificial Disc Replacement

This study aims to develop an integrated approach for 3D lumbar vertebral biomodel design and analysis, specifically targeting unilevel disc degeneration and the replacement of lumbar artificial discs. Key objectives include improving existing design methods through 3D techniques, inverse modeling, and an engineering biomodel preparation protocol. Additionally, the study evaluates mechanical properties in the implantation area and between disc components to gauge the effectiveness of artificial discs in restoring functional movement within the studied biological model. The construction of a biological model representing the L3–L4 functional spinal unit was based on measurements from radiographic images and computed tomography data obtained from the study sample. The 3D finite element method in Ansys software (v. 19.2, ANSYS, Inc., Canonsburg, PA, USA) was used to monitor the distribution of equivalent stress values within the core of the two artificial discs and the behavior of vertebral bone components in the model. This approach enabled the creation of personalized digital models tailored to the specific implantation requirements of each patient. Stress analysis identified critical areas within the disc cores, suggesting potential design modifications to optimize artificial disc performance, such as selectively increasing core thickness in specific regions and considering adjustments during implantation. For example, preserving part of the lateral annulus fibrosus from the degenerative disc and maintaining the anterior and posterior longitudinal ligaments may play a crucial role in balancing the forces and moments experienced by the lumbar section. This study provides valuable insights into the development of patient-specific solutions for lumbar disc degeneration cases, with the potential for enhancing artificial disc design and implantation techniques for improved functional outcomes.

Different cervical vertebral bone quality scores for bone mineral density assessment for the patients with cervical degenerative disease undergoing ACCF/ACDF: computed tomography and magnetic resonance imaging-based study

BackgroundBone mineral density (BMD) is important for the outcome of cervical spine surgery. As the gold standard of assessing BMD, dual-energy X-ray absorptiometry scans are often not ordered or go unreviewed in patients’ charts. As the supplement, MRI-based vertebral bone quality (VBQ) was found to accurately predict osteopenia/osteoporosis and postoperative complications in lumbar spine. However, discussion of the efficiency of VBQ in cervical spine is lacking. And measurement methods of VBQ in cervical spine are diverse and not universally acknowledged like lumbar spine. We aimed to compare the predictive performance of three kinds of different Cervical-VBQ (C-VBQ) scores for bone mineral density assessment in patients undergoing cervical spine surgery. HU value of cervical spine was set as a reference.MethodsAdult patients receiving cervical spine surgery for degenerative diseases were retrospectively included between Jan 2015 and Dec 2022 in our hospital. The VBQ scores and HU value were measured from preoperative MRI and CT. The correlation between HU value/C-VBQs (named C-VBQ1/2/3 according to different calculating methods) and DEXA T-score was analyzed using univariate linear correlation and Pearson’s correlation. We evaluated the predictive performance of those two parameters and achieved the most appropriate cutoff value by comparing the receiver operating characteristic (ROC) curves.Results106 patients (34 patients with T ≥ − 1.0 vs 72 patients with T < − 1.0) were included (mean age: 51.95 ± 10.94, 48 men). According to Pearson correlation analysis, C-VBQ1/2/3 and HU value were all significantly correlated to DEXA T-score (Correlation Coefficient (r): C-VBQ1: − 0.393, C-VBQ2: − 0.368, C-VBQ3: − 0.395, HU value: 0.417, p < 0.001). The area under the ROC curve (AUC) was calculated (C-VBQ1: 0.717, C-VBQ2: 0.717, C-VBQ3: 0.727, HU value: 0.746). The AUC of the combination of C-VBQ3 and HU value was 0.786. At last, the most appropriate cutoff value was determined (C-VBQ1: 3.175, C-VBQ2: 3.005, C-VBQ3: 2.99, HU value: 299.85 HU).ConclusionsDifferent MRI-based C-VBQ scores could all be potential and alternative tools for opportunistically screening patients with osteopenia and osteoporosis before cervical spine surgery. Among them, C-VBQ calculated in ASIC2–C7/SIT1-CSF performed better. We advised patients with C-VBQ higher than cutoff value to accept further BMD examination.

Sex differences in the accuracy of vertebral bone quality score assessing bone density in patients undergoing lumbar spinal fusion.

Low bone mineral density (BMD) significantly increases the risk of complications in patients undergoing spinal fusion. Existing evidence indicates that traditional dual-energy x-ray absorptiometry (DEXA) and quantitative CT (QCT) screening are underutilized in spine surgery. The MRI-based vertebral bone quality (VBQ) score provides a tool for primary screening of bone density. The validity of this score as a predictor across sexes has not been investigated. This study aimed to explore the effect of sex on the diagnostic efficacy of the VBQ in predicting osteopenia/osteoporosis and whether a sex-specific threshold exists. In this retrospective cohort study, patients who underwent lumbar fusion at a tertiary care center were reviewed. VBQ was obtained by noncontrast T1-weighted MRI. Patients were stratified according to sex and bone density. Data were analyzed between the groups. Pearson correlation analysis and linear regression were used to analyze the correlation between the VBQ and DEXA T values. Receiver operating characteristic (ROC) curve analysis, including area under the curve (AUC) calculation, was used to evaluate the predictive performance of VBQ for low BMD in both sexes. A total of 271 patients (92 male, 179 female patients) were analyzed. The correlation coefficient between VBQ and the lowest T value was -0.40 for male and -0.554 for female patients. In comparing the bone density subgroups, among male patients a significant difference in the VBQ scores was observed only between the normal and osteoporosis subgroups (p = 0.012). VBQ demonstrated statistically significant differences among female patients across all three subgroups (p < 0.001). The ROC analysis revealed that the predictive performance of VBQ in detecting low BMD was more consistent with the gold-standard DEXA results in female than in male patients (AUC 0.647 vs AUC 0.823, p = 0.02). The optimal thresholds were similar in both sexes. Compared with male patients, VBQ has better discrimination between female patients with low BMD and those with normal bone density. Although the correlation between VBQ and bone density is weaker in male than in female patients, the optimal thresholds are similar in both sexes.

Evaluation of multidetector CT Hounsfield unit measurements as a predictor of efficacy and complications in percutaneous vertebroplasty for osteoporotic vertebral compression fractures

IntroductionMore than 30 years after the initial experience of Galibert and Deramond with percutaneous vertebroplasty, the procedure has gone through countless refinements and clinical evaluations. Predictors for the success and failure of the procedure in the literature vary and are focused on the duration of complaints, type of fracture, presence of edema on MRI scans, etc. We propose using a quantitative method based on a standard CT examination of the thoracic or lumbar spine to assess the risks and potential success of performing vertebroplasty.Materials and methodsThis is a single-center prospective observational study on 139 patients treated with percutaneous vertebroplasty (pVPL) for a single symptomatic osteoporotic vertebral compression fracture (OVCF). We measured the levels of disability and pain preoperatively and again at the 3-, 6- and 12-month marks using the standardized VAS and ODI questionnaires. Every patient in the study was evaluated with postoperative multidetector CT (MDCT) to determine the presence, extent, and localization of vertebral cement leakage and to measure the adjacent vertebrae’s minimal and mean density in Hounsfield units (HUmin and HUmean, respectively).ResultsWe determined that a slight (r = −0.201) but statistically significant (p = 0.018) correlation existed between HU measurements taken from radiologically intact adjacent vertebrae and the procedure’s effect concerning the pain levels at the 3-month follow-up. This correlation failed to reach statistical significance at 12 months (p = 0.072). We found no statistically significant relationship between low vertebral cancellous bone density and cement leakage on postoperative scans (p = 0.6 for HUmin and p = 0.74 for HUmean).ConclusionWe have moderately strong data that show a negative correlation between the mean values of vertebral cancellous bone density in patients with OVCF and the effect of pVPL in reducing pain. Lower bone densities, measured this way, showed no increased risk of cement leakage.

Cervical Vertebral Bone Quality Score Independently Predicts Zero-Profile Cage Subsidence After Single-Level Anterior Cervical Discectomy and Fusion

ObjectiveThis is the first study to evaluate the predictive value of the cervical vertebral bone quality (VBQ) score on zero-profile cage (ZPC) subsidence after anterior cervical discectomy and fusion (ACDF) using the HU value of computed tomography (CT) as the reference. MethodsA total of 89 patients with at least 1 year of follow-up who underwent single-level ACDF with ZPC were retrospectively and consecutively included. VBQ and HU value were determined from preoperative T1-weighted MRI and CT. Subsidence was defined as ≥2 mm of migration of the cage into the superior or inferior endplate or both using lateral cervical spine radiography. The results were subjected to statistical analysis. ResultsSubsidence was observed among 16 of the 89 study patients (Subsidence rate:18.0%). The mean VBQ score was 2.94±0.820 for patients with subsidence and 2.33±0.814 for patients without subsidence. The multivariable analysis demonstrated that only an increased VBQ score (OR:1.823, 95%CI: 0.918,3.620, p=0.001) was associated with an increased rate of cage subsidence. There was a significant and moderate correlation between HU and VBQ (r = -0.507, P < 0.001). Using receiver operating characteristic curves, the area under the curve (AUC) was 0.785, and the most appropriate threshold of VBQ was 2.68 (sensitivity 72.7%, specificity 82.1%). ConclusionsThe VBQ score may be a valuable tool for independently predicting zero-profile cage subsidence after single-level ACDF.

1287. Assessing the Utility of Vertebral Body / Disc Space Fluid Cell Differential in the Diagnosis of Native Vertebral Osteomyelitis

Abstract Background Current approaches to diagnosing suspected native vertebral osteomyelitis (NVO) rely on imaging and microbiological workup, including blood and CT-guided biopsy cultures. These existing diagnostic methods often result in ambiguity, necessitating additional tests to distinguish NVO from its mimics. Our study aims to validate pilot findings demonstrating that an elevated neutrophil differential (PMN) in vertebral bone biopsy/ disc space fluid aspirate is associated with NVO. This may allow stratification of patients with suspected NVO into those who can be monitored closely versus those who may benefit from further invasive testing or empiric antibiotic therapy (Fig 1). Figure 1: Proposed workup of patients with suspected native vertebral osteomyelitis guided by disc space/ vertebral body neutrophil (PMN) differential. Methods This analysis examines a subset of patients from a prospective cohort study, enrolling adults referred to Mayo Clinic's neuroradiology department for spine biopsy. After collecting routine clinical specimens, the needle is rinsed with saline into an EDTA tube for automated cell count and differential analysis. To evaluate the predictive capacity of neutrophil (PMN) differential for NVO, logistic regression models were employed, and receiver operating characteristic (ROC) curve analyses were conducted for various PMN percentage cutoff points. Results In this preliminary analysis, 39 patients were included, comprising 7 patients with NVO and 32 patients with alternative diagnoses. Baseline characteristics are presented in Table 1. All NVO patients received antibiotics within two weeks of the spine biopsy. The median biopsy sample PMN percentage for NVO patients was 83.0 (77.5-88.0), compared to 65.0 (56.5-69.5) for those without NVO (p=0.005) (Fig 2A). The estimated relationship between the probability of NVO and each measure across the full range of percentages is illustrated in Fig 2B. The optimal ROC curve point corresponds to a PMN differential of 72.5% (sensitivity=0.86, specificity=0.81) (Fig 3).Table 1:Baseline Characteristics of Patients Included in the Preliminary AnalysisFigure 2:A) Distribution of spine biopsy neutrophil percent by native vertebral osteomyelitis (NVO) status, B) Loess nonparametric smoother showing the relationship between the probability of NVO and biopsy sample neutrophil percentage.Figure 3:ROC curve analysis of neutrophil percent and NVO Conclusion This preliminary analysis indicates that an elevated PMN differential in spine biopsy samples may serve as a valuable diagnostic tool for NVO, with results seemingly unaffected by recent antibiotic intake. The PMN differential cutoff of 72.5% exhibited notable sensitivity and specificity. Investigations are ongoing to further validate these findings Disclosures Brett Freedman, MD, Clear Choice Therapeutics: Stocks/Bonds|Medtronic: Grant/Research Support|Neuroinnovations: Stocks/Bonds Aaron J. Tande, M.D., Musculoskeletal Infection Society: Board Member|Wolters Kluwer Health - Lippincott Williams &amp; Wilkins: Publishing royalties, financial or material support

Biomimetic Inspired Hydrogels for Regenerative Vertebral Body Stenting.

This review aims to explore the potential of biomimetic hydrogels as an alternative to bone cement in vertebral body stenting (VBS), a minimally invasive treatment for vertebral compression fractures. The use of bone cement in VBS procedures can lead to complications such as incomplete fracture reduction and cement leakage. Biomimetic hydrogels have gained significant attention as potential biomaterial alternatives for VBS due to their unique properties, including tuneable therapeutic and mechanical properties. Over the past decade, there has been significant advancements in the development of biomimetic hydrogels for bone regeneration, employing a wide range of approaches to enhance the structural and functional properties of hydrogels. Biomimetic hydrogels hold significant promise as safer and reparative alternatives to bone cement for VBS procedures. However, further research and development in this field are necessary to explore the full potential of hydrogel-based systems for vertebral bone repair.

Optimizing percutaneous vertebroplasty: extra-facet puncture for osteoporotic vertebral compression fractures

PurposeTo assess the safety and efficacy of the extra-facet puncture technique applied in unilateral percutaneous vertebroplasty (PVP) for treating osteoporotic vertebral compression fractures.MethodsDemographics (age, gender, body mass index and underlying diseases) were recorded for analyzing. Visual analog scale (VAS) and Oswestry Disability Index (ODI) scores as well as their corresponding minimal clinically important difference (MCID) were used to evaluate clinical outcomes. The segmental kyphotic angle, the vertebral compression ratio and bone cement distribution pattern were evaluated by the plain radiographs. The facet joint violation (FJV) was defined by the postoperative computed tomography scan. Binary logistic regression analysis was performed to investigate relationships between multiple risk factors and residual back pain.ResultsVAS and ODI scores in both traditional puncture group and extra-facet puncture group were significantly decreased after PVP surgery (p < 0.05). However, no significant difference was observed between the two groups according to VAS and ODI scores. The proportion of patients achieving MCID of VAS and ODI scores was higher in extra-facet puncture group as compared to traditional puncture group within a month (p < 0.05). Finally, multivariate logistic regression analysis showed that FJV (odds ratio 16.38, p < 0.001) and unilateral bone cement distribution (OR 5.576, p = 0.020) were significant predictors of residual back pain after PVP surgery.ConclusionsExtra-facet puncture percutaneous vertebroplasty can decrease the risk of FJV and it also has the advantage of more satisfied bone cement distribution.

MRI‑based vertebral bone quality score is a comprehensive index reflecting the quality of bone and paravertebral muscle

BACKGROUNDRecently, vertebral bone quality (VBQ) score has been shown to predict bone mineral density (BMD) and spine-related postoperative complications. However, in clinical work, we found that patients with higher VBQ scores also had more severe paravertebral muscle degeneration. PURPOSETo explore the ability of the VBQ score to evaluate BMD and paravertebral muscle quality. STUDY DESIGN/SETTINGRetrospective single-center cohort. PATIENT SAMPLEPatients in the spinal surgery department of our hospital. OUTCOME MEASURESBone mineral density and T-score were measured by dual-energy X-ray absorptiometry (DXA). The Picture Archiving and Communication Systems (PACS) measured the cross-sectional area (CSA) of the paravertebral muscles. Image J software was used to measure the degree of fat infiltration (DFF) of the paraspinal muscle. METHODSPatients who underwent lumbar MRI and DXA simultaneously within two weeks were enrolled. The VBQ score was calculated using T1-weighted lumbar MRI images. Firstly, BMD-related and muscle-related parameters of patients with different VBQ scores were compared. Then, the correlation coefficients between the VBQ score and the parameters of BMD and paravertebral muscle were calculated. Finally, multivariate linear analysis was used to compare the contribution of each variable to the VBQ score. RESULTSA total of 101 patients were eventually included in this study for analysis. When the VBQ score was greater than 3.0, the patients were mostly female, older, less likely to smoke, and had lower BMD. Interestingly, we found that patients with VBQ scores greater than 3.0 had smaller CSA of the paravertebral muscles (ES: 17.53±3.36 vs 19.13±3.97, p=.032; total: 29.59±5.27 vs 34.12±7.02, p<.001) and higher DFF (MF: 22.47±5.93 vs 19.64±5.28, p=.015; ES: 17.71±4.67 vs 15.74±4.62, p=.038; PM: 13.70±3.32 vs 11.33±3.02, p<.001; average: 17.96±3.78 vs 15.57±3.42, p=.001). The VBQ score was negatively correlated with the CSA (MF: r=−0.316, p=.001; ES: r =−0.388, p=.001; PM: r=0.388, p=.001) and positively correlated with the DFF (MF: r=0.344, p<.001; ES: r=0.439, p<.001; PM: =0.416, p<.001). In multivariate linear analysis, BMD, total CSA, and average DFF determined the value of the VBQ score, and the contribution of paravertebral muscle was higher than that of BMD (BMD: r=−0.203, p=.024; total CSA: r=−0.294, p=.003; average DFF: r=0.261, p=.011). CONCLUSIONSThis study is the first to find a positive association between the VBQ score and paravertebral muscle degeneration, and this association may be independent of BMD. VBQ can reflect the quality of bone and paravertebral muscle, which is its special advantage in clinical application.

Assessing the utility of MRI-based vertebral bone quality (VBQ) for predicting lumbar pedicle screw loosening.

Retrospective cohort. The purpose of this study is to assess the potential of utilizing the MRI-based vertebral bone quality (VBQ) score as a predictive tool for pedicle screw loosening (PSL) in patients who have undergone pedicle screw fixation and to identify risk factors associated with VBQ scores. One hundred and sixteen patients who had undergone pedicle screw fixation between December 2019 and January 2021 and had more than a year of follow-up were divided into two groups of PSL and non-PSL. The radiological and clinical parameters investigated were age, gender, body mass index, the VBQ score, length of fusion and the DXA T-score. Of the 116 patients included in the study, 22 patients developed pedicle screw loosening after surgery (18.97%). VBQ score of PSL group was higher than the non-PSL group (3.61 ± 0.63 vs. 2. 86 ± 0.43, p < 0.001). According to logistic regression, PSL was independently linked with a higher VBQ score (OR = 3.555, 95% confidence interval [1.620-7.802], p < 0.005). The AUC of predicting screw loosening was 0.774 (p < 0.001) for VBQ score, and the best threshold was 3.055 (sensitivity, 81.8%; specificity, 71.3%). High VBQ score was associated with age (r (114) = 0.29, p = 0.002), while it was not negatively correlated with T-scores of each part. VBQ score is an independent predictor of pedicle screw loosening, with higher scores indicating a greater risk. Our results showed that older patients and women had higher VBQ scores.

Opportunistic screening for osteopathy with routine abdominal computed tomography scan in chronic pancreatitis

Background and aimsLumbar vertebral bone attenuation, measured in Hounsfield units (HU) can indirectly indicate the bone mineral density (BMD). The aim of this study is to determine the optimal HU threshold on abdominal computed tomography (CT) scans to detect osteopathy in patients with chronic pancreatitis (CP). MethodsThis cross-sectional study included patients with CP who underwent CT scans to measure HU at L1 to L4 vertebrae. The mean lumbar vertebral attenuation of female renal transplant donors, aged 20–30 years was utilized to calculate the T-scoreHU of all patients at each vertebral level. Receiver operator characteristic analysis was used to determine the HU and T-scoreHU for diagnosis of osteopathy in patients with CP. Dual-energy X-ray absorptiometry value was used to categorize osteopenia and osteoporosis. ResultsA total of 175 patients (mean age, 34.5 ± 10.9 years; 72 % males) and 33 female renal transplant donors (mean age, 28 ± 2.4 years) were included. A threshold HU value 212 or T scoreHU of −1.80 at L1 vertebra was found to have a 78 % sensitivity and 70 % specificity for differentiating between osteoporosis and non-osteoporosis (osteopenia and normal BMD). Similarly, a threshold HU value of 254 or a T-scoreHU of −0.46 at L1 vertebra had 78 % sensitivity and 71 % specificity for distinguishing between normal and low BMD (osteoporosis and osteopenia). ConclusionAbdominal CT images, which are routinely performed in chronic pancreatitis, can be used for opportunistic screening of osteoporosis and osteopenia without additional cost or radiation exposure.

The Association between High Preoperative MRI-based Vertebral Bone Quality (VBQ) Score and Titanium Mesh Cage Subsidence after Anterior Cervical Corpectomy and Fusion.

Recently, the MRI-based vertebral bone quality (VBQ) score has been shown to correlate with Hounsfeld units (HU) value, dual-energy X-ray absorptiometry (DEXA) T-score and predict osteoporotic fractures. Preoperative cervical HU value is an independent correlative factor for early titanium mesh cage (TMC) subsidence after anterior cervical corpectomy and fusion (ACCF). However, to date the direct association between cervical VBQ score and TMC subsidence has not been studied. This study aims to investigate the predictive effect of cervical VBQ score derived from sagittal non-contrast-enhanced T1-weighted MRI on the early TMC subsidence after ACCF. Patients who underwent one-level ACCF from January 2016 to January 2020 were included. We retrospectively collected baseline data on age, sex, body mass index (BMI), disease type, level of surgery and radiology parameters. The cervical VBQ score was measured using preoperative non-contrast-enhanced T1-weighted MRI. Univariate and multivariate logistic regression analysis were performed to screen the independent risk factors of TMC subsidence. The receiver operating characteristic (ROC) curve and area under curve (AUC) were performed to assess the predictive ability of TMC subsidence based on the cervical VBQ score. Spearman correlation analysis was used to determine the correlations between the cervical VBQ score and TMC subsidence. A total of 134 patients who underwent one-level ACCF were included in this study, and 46 (34.33%) patients had TMC subsidence. Univariable analyses demonstrated that the age, TMC placement depth and VBQ score were associated with subsidence. The cervical VBQ score in the subsidence group was significantly higher than that in the no subsidence group (3.75 ± 0.45 vs. 3.20 ± 0.42, p < 0.001). The multivariate logistic regression analysis proved that the higher VBQ score (odds ratio[OR] = 13.563, 95% confidence interval [CI] 4.968 - 37.031, p < 0.001) was the only variable that significantly predicted subsidence. Using a VBQ score cutoff value of 3.445, the cervical VBQ score yielded a sensitivity of 69.6% and a specificity of 85.2% with an AUC of 0.810 to differentiate patients with subsidence and with no subsidence. Preoperative higher cervical VBQ score is an independent risk factor for TMC subsidence after ACCF. The cervical VBQ score may be a valuable tool for assisting in distinguishing the presence of TMC subsidence.

Late Triassic–Early Jurassic continental vertebrates and their environmental context from the Junggar Basin, Xinjiang, NW China

Abstract Vertebrate assemblages from the Junggar Basin in Xinjiang, China, are the only ones known from palaeo-Arctic continental strata of Late Triassic and Early Jurassic age. Here we present a preliminary description of these new assemblages, focusing on the underappreciated Arctic palaeolatitude and winter freezing of this coal-bearing sequence. Mostly collected during NIGPAS-led stratigraphic studies in the 2016–17 field seasons, new assemblages include: (1) small to large sculptured palaeonisciform cranial elements and scales, small associated palaeonisciforms, a sauropterygian tooth, large-dinosaur bioturbation and additional unidentified small vertebrate bones from the Haojiagou Formation (?upper Norian–Rhaetian); (2) a medium-sized brontozoid dinosaur footprint and a previously described possible Anomoepus track from the Badaowan Formation (Hettangian–?Pliensbachian); and (3) a hybodont shark egg case of the form taxon Palaeoxyris (only the third reported from Early Jurassic age strata of China), numerous associated and fragmentary small palaeonisciform remains (including one partial skull and several small skeletons), and another possible Anomoepus track and associated dinoturbation from the Sangonghe Formation (?Pliensbachian–Toarcian). A possible ash associated with the aforementioned lower Sangonghe fish skull has produced a laser ablation inductively coupled plasma mass spectrometry age of roughly 186 Ma, consistent with a Pliensbachian age. We are optimistic that there will be many additional discoveries from early Mesozoic age strata of the Junggar Basin, the importance of which for understanding Earth system processes cannot be overemphasized.

Aconine attenuates osteoclast-mediated bone resorption and ferroptosis to improve osteoporosis via inhibiting NF-κB signaling.

Osteoporosis (OP), a prevalent public health concern primarily caused by osteoclast-induced bone resorption, requires potential therapeutic interventions. Natural compounds show potential as therapeutics for postmenopausal OP. Emerging evidence from in vitro osteoclastogenesis assay suggests that aconine (AC) serves as an osteoclast differentiation regulator without causing cytotoxicity. However, the in vivo functions of AC in various OP models need clarification. To address this, we administered intraperitoneal injections of AC to ovariectomy (OVX)-induced OP mice for 8 weeks and found that AC effectively reversed the OP phenotype of OVX mice, leading to a reduction in vertebral bone loss and restoration of high bone turnover markers. Specifically, AC significantly suppressed osteoclastogenesis in vivo and in vitro by decreasing the expression of osteoclast-specific genes such as NFATc1, c-Fos, Cathepsin K, and Mmp9. Importantly, AC can regulate osteoclast ferroptosis by suppressing Gpx4 and upregulating Acsl4, which is achieved through inhibition of the phosphorylation of I-κB and p65 in the NF-κB signaling pathway. These findings suggest that AC is a potential therapeutic option for managing OP by suppressing NF-κB signaling-mediated osteoclast ferroptosis and formation.

Changes in Vertebral Bone Density and Paraspinal Muscle Morphology Following Spaceflight and 1 Year Readaptation on Earth.

Astronauts have an increased risk of back pain and disc herniation upon returning to Earth. Thus, it is imperative to understand the effects of spaceflight and readaptation to gravity on the musculoskeletal tissues of the spine. Here we investigated whether ~6 months of spaceflight led to regional differences in bone loss within the vertebral body. Additionally, we evaluated the relationships between vertebral bone density and paraspinal muscle morphology before flight, after flight, and after readaptation on Earth. We measured vertebral trabecular bone mineral density (Tb.BMD), paraspinal muscle cross-sectional area (CSA), and muscle density in 17 astronauts using computed tomography (CT) images of the lumbar spine obtained before flight (before flight, n = 17), after flight (spaceflight, n = 17), and ~12 months of readaptation to gravitational loading on Earth (follow-up, n = 15). Spaceflight-induced declines in Tb.BMD were greater in the superior region of the vertebral body (-6.7%) than the inferior (-3.1%, p = 0.052 versus superior region) and transverse regions (-4.3%, p = 0.057 versus superior region). After a year of readaptation to Earth's gravity, Tb.BMD in the transverse region remained significantly below preflight levels (-4.66%, p = 0.0094). Paraspinal muscle CSA and muscle density declined -1.0% (p = 0.005) and -0.83% (p = 0.001) per month of spaceflight, respectively. Ultimately, bone loss in the superior vertebral body, along with fatty infiltration of paraspinal muscles and incomplete recovery even after a year of readaptation on Earth, may contribute to spinal pathology in long-duration astronauts. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Skeletal Tuberculosis in Pediatric Population for 15 Years; Twenty Cases from Southern Turkey.

Skeletal tuberculosis is rarely seen among extrapulmonary tuberculosis, especially in childhood because the diagnosis may be delayed for years due to diagnostic difficulties. In this study, it was aimed to evaluate the clinical characteristics, methods used in diagnosis, treatment specifics, and prognosis of patients diagnosed with bone joint tuberculosis in childhood. Twenty patients diagnosed with skeletal tuberculosis in our hospital between Jan 1, 2006, and Jan 1, 2021, were evaluated retrospectively. The age of the patients ranged from seven to 191 months. 70% of the patients presented with complaints of pain, 50% with swelling, and 20% with limping. The duration of the complaints was 3.82 ± 4 months on average. While 65% of the patients had isolated skeletal TB, 30% were accompanied with pulmonary tuberculosis. Tuberculin skin test (TST) was positive in 13 (65%) patients. Seven (35%) of the patients were diagnosed with proven TB. The most frequent involvement was seen in knee bones (25%), followed by vertebra (15%), foot (15%), and wrist (15%) bones. In the radiological findings, 65% of the patients had mass, 45% destruction, 35% enhancement/edema, 5% calcification/sclerosis, 5% cyst, and 35% soft tissue abscess. In the follow-up, 50% of the patients recovered without sequelae. Skeletal tuberculosis can easily be missed in childhood due to its slow insidious course, non-specific symptoms, and bone findings, resulting in delayed diagnosis and may lead to sequelae which affect lifelong quality of life. We should keep the possibility of skeletal tuberculosis in mind when we see the patients with limping or localized lesions accompanied with pain or swelling.

Gamma-aminobutyric acid (GABA)-mediated bone formation and its implications for anti-osteoporosis strategies: Exploring the relation between GABA and GABA receptors

Osteoporosis is a significant global health concern, linked to reduced bone density and an increased fracture risk, with effective treatments still lacking. This study explored the potential of gamma-aminobutyric acid (GABA) and its receptors as a novel approach to promote osteogenesis and address osteoporosis. GABA concentrations up to 10 mM were well-tolerated by MC3T3-E1 preosteoblast, stimulating osteoblast differentiation and mineralization in a concentration- and time-dependent manner. In vivo experiments with zebrafish larvae demonstrated the ability of GABA to improve vertebral formation and enhanced bone density, indicating the potential therapeutic value for osteoporosis. Notably, GABA countered the adverse effects of prednisolone on vertebral formation, bone density, and osteogenic gene expression in zebrafish larvae, suggesting a promising therapeutic solution to counteract corticosteroid-induced osteoporosis. Moreover, our study highlighted the involvement of GABA receptors in mediating the observed osteogenic effects. By using GABAA, GABAB, and GABAC receptor antagonists, we demonstrated that blocking these receptors attenuated GABA-induced osteoblast differentiation and vertebral formation in both MC3T3-E1 cells and zebrafish larvae, underscoring the importance of GABA receptor interactions in promoting bone formation. In conclusion, these findings underscore the osteogenic potential of GABA and its ability to mitigate the detrimental effects of corticosteroids on bone health. Targeting GABA and its receptors could be a promising strategy for the development of novel therapeutic interventions to address osteoporosis. However, further investigations are warranted to fully elucidate the underlying molecular mechanism of GABA and its clinical applications in treating osteoporosis.