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INTRODUCTION: The trabecular bone score (TBS) has emerged as a convenient measure for assessing the microstructure of trabecular bone in the second through fourth lumbar vertebrae (L2-4) and can be conducted concurrently with bone mineral density (BMD) assessment. This study was performed to evaluate changes in BMD and the TBS during ADT for prostate cancer. MATERIALS AND METHODS: Consecutive patients who had prostate cancer without bone metastases at Kobe University Hospital were studied from March 2020 to December 2021. BMD and TBS were measured every 6 months from the start of treatment using Hologic Horizon devices (Hologic, Inc., Marlborough, MA, USA). RESULTS: Thirty-four patients were followed for 2 years. Significant declines in BMD (-3.8% for femoral neck, -4.2% for total hip, and -6.1% for lumbar spine) and TBS (-16.6%) were noted after 2 years of ADT. Correlation analyses revealed a weak correlation between lumbar spine BMD and TBS at ADT initiation, but this correlation strengthened after 2 years. The multiple regression analysis results suggested that the rate of BMD loss may be slower in patients with a preserved pretreatment TBS. CONCLUSION: In patients without bone metastases undergoing ADT for prostate cancer, notable decreases were found in both BMD and TBS over a 2-year treatment period. Factors influencing the TBS decline remain unclear; however, patients with a lower pretreatment TBS exhibited a more rapid decline in BMD.

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Introduction: Bone mineral density (BMD) is reduced in patients with human immunodeficiency virus (HIV) infection. Trabecular bone score (TBS) is an additional feature calculated by dual-energy X ray absorption (DXA) that measures texture inhomogeneity at lumbar spine level, providing an index of bone microarchitecture. However, its clinical value still needs to be fully addressed. Aims of the study were to assess BMD and TBS in a cohort of patients with HIV compared to a population of healthy subjects and to investigate the prognostic value of TBS in HIV infected patients. Method: Bone health was assessed by DXA in 165 patients with HIV infection (120 men, mean age 40 ± 7 years) and in 164 healthy subjects (53 male, mean age 37 ± 10 years). BMD was measured at level of lumbar spine (L1-L4), femoral neck and total hip. TBS was computed from the images of lumbar spine using machine proprietary software. Results: BMD at femoral neck level was similar in HIV infected patients and healthy subjects (p = 0.57), whereas BMD measured in total femur was lower in HIV infected patients compared to healthy subjects (p < 0.05). Although mean BMD in lumbar spine was similar between HIV infected patients and healthy subjects (p = 0.90), mean lumbar TBS was lower in patients with HIV infection compared to healthy subjects (p < 0.05). Age, sex and HIV infection resulted independent predictors of reduced TBS. In HIV infected patients age, sex and protease inhibitor duration resulted independent predictors of reduced TBS. TBS was a significant predictor of vertebral fractures during follow-up (p < 0.05). Conclusion: Patients with HIV infection have a significant reduction of TBS, a texture parameter related to bone microarchitecture that may provide skeletal information that is not captured from the standard BMD measurement.

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The "gold standard" for the assessment of trabecular bone structure is high-resolution micro-CT. In this technical note, we test the influence of initial scan resolution and post hoc downsampling on the quantitative and qualitative analysis of trabecular bone in a Gorilla tibia. We analyzed trabecular morphology in the right distal tibia of one Gorilla gorilla individual to investigate the impact of variation in voxel size on measured trabecular variables. For each version of the micro-CT volume, trabecular bone was segmented using the medical image analysis method. Holistic morphometric analysis was then used to analyze bone volume (BV/TV), anisotropy (DA), trabecular thickness (Tb.Th), spacing (Tb.Sp), and number (Tb.N). Increasing voxel size during initial scanning was found to have a strong impact on DA and Tb.Th measures, while BV/TV, Tb.Sp, and Tb.N were found to be less sensitive to variations in initial scan resolution. All tested parameters were not substantially influenced by downsampling up to 90 µm resolution. Color maps of BV/TV and DA also retained their distribution up to 90 µm. This study is the first to examine the effect of variation in micro-CT voxel size on the analysis of trabecular bone structure using whole epiphysis approaches. Our results indicate that microstructural variables may be measured for most trabecular parameters up to a voxel size of 90 µm for both scan and downsampled resolutions. Moreover, if only BV/TV, Tb.Sp or Tb.N is measured, even larger voxel sizes might be used without substantially affecting the results.

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The primary function of the tetrapod jaw is to transmit jaw muscle forces to bite points. The routes of force transfer in the jaw have never been studied, but can be quantified using load paths--the shortest, stiffest routes from regions of force application to support constraints. Here we use load path analysis to map force transfer from muscle attachments to bite point and jaw joint, and to evaluate how different configurations of trabecular and cortical bone affect load paths. We created three models of the mandible of the Virginia opossum, Didelphis virginiana, each with a cortical bone shell, but with different material properties for the internal spaces: a cortical-trabecular model, in which the interior space is modeled with bulk properties of trabecular bone; a cortical-hollow model, in which trabeculae and mandibular canal are modeled as hollow; and a solid-cortical model, in which the interior is modeled as cortical bone. The models were compared with published in vivo bite force and bone strain data, and the load paths calculated for each model. The cortical-trabecular model, which most closely approximates the actual morphology, was best validated by in vivo data. In all three models the load path was confined to cortical bone, although its route within the cortex varied depending on the material properties of the inner model. Our analysis shows that most of the force is transferred through the cortical, rather than trabecular bone, and highlights the potential of load path analysis for understanding form-function relationships in the skeleton.

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OBJECTIVE: There is limited information on population-specific norms of trabecular-bone-score (TBS) and its associated factors. Here, we provide norms of TBS in Asian-Indians and its relationship with serum 25-hydroxyvitamin D [25(OH)D] and intact-parathyroid hormone (iPTH). PARTICIPANTS AND MEASUREMENTS: TBS, bone-mineral-density (BMD), and vertebral-fractures (VFs) were assessed using dual-energy X-ray absorptiometry in 923 healthy Asian-Indians (aged 20-60 years). Serum 25(OH)D, iPTH, T4/TSH,, glycosylated-haemoglobin (HbA1c) were measured and associations with TBS assessed using multivariable linear regression. Subjects with BMD Z-score ≤ -2.0 or ≥2.0 at any sites, VFs, TSH > 10.0 or <0.05 µIU/ml, blood-glucose >11.1 mmol/L or HbA1c > 8.0% were excluded for generating Asian-Indian norms. RESULTS: TBS norms were generated in 744 healthy Asian-Indians (M:F,389:385). The cut-offs generated for 'normal', 'partially-degraded', and 'degraded' TBS were >1.305, 1.204-1.305 and <1.204, respectively. Mean TBS was lower in females than males (p < .001). There was 75% congruency in TBS categories between Asian-Indian and existing norms. Specificity (97.8 vs. 77.9%, p < .001) and diagnostic-accuracy (97.8% vs. 78.4%, p < .001) of TBS to detect osteoporosis were higher with Asian-Indian norms. The sensitivity of 'partially-degraded' TBS to diagnose osteopenia was also higher with Asian-Indian norms. In multivariable regression, gender, body-mass-index (BMI), BMD-L1-L4, serum PTH, daily dietary-calorie intake and calcium intake were associated with TBS. Though 25(OH)D inversely correlated with PTH, 25(OH)D was not associated with TBS. CONCLUSION: This study provides norms for TBS in Asian-Indians with gender-specific differences. Increasing age and higher BMI were associated with lower TBS. Associations of TBS with circulating PTH and/or 25(OH)D need confirmation in further studies.

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CONTEXT: Chronic use of proton pump inhibitors (PPIs) has been associated with an increase in bone fragility. However, evidence on the effect of chronic PPI use on bone density is conflicting, and data on bone microarchitectural quality are scarce. OBJECTIVE: The primary aim of this study was to evaluate whether trabecular bone microarchitecture, assessed by trabecular bone score (TBS), is altered in chronic PPI users. The association between PPI use and bone density was also evaluated as a secondary endpoint. METHODS: We extracted individual patient data from the 2005-2008 cycles of the population-based National Health and Nutrition Examination Survey (NHANES), in which lumbar spine dual-energy X-ray absorptiometry (DXA) scans were acquired. TBS values were calculated from DXA images using a dedicated software. Multivariable linear regression analyses stratified by sex were performed to evaluate the association of chronic PPI use with TBS and bone mineral density (BMD), adjusting for relevant confounders. RESULTS: A total of 7478 subjects were included (3961 men, 3517 women). After adjustment for relevant confounders, chronic PPI use was associated with a worse bone health profile in men, with lower TBS (-0.039, 95%CI:[-0.058, -0.020], p<0.001), lumbar spine T-score (-0.27, 95%CI:[-0.49, -0.05], p=0.018), total hip T-score (-0.20, 95%CI:[-0.39, -0.01], p=0.038), and femoral neck T-score (-0.21, 95%CI:[-0.42, -0.01], p=0.045). Notably, the association between chronic PPI use and degraded TBS remained statistically significant even after further adjustment for BMD at lumbar spine and femoral neck (-0.026, 95%CI:[-0.039, -0.012], p=0.001). In contrast, no significant association was observed between chronic PPI use and either TBS or BMD in women. CONCLUSIONS: Chronic PPI use is associated with degraded trabecular bone quality in men, even after adjustment for BMD. No association was observed in women.

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Understanding bone surface curvatures is crucial for the advancement of bone material design, as these curvatures play a significant role in the mechanical behavior and functionality of bone structures. Previous studies have demonstrated that bone surface curvature distributions could be used to characterize bone geometry and have been proposed as key parameters for biomimetic microstructure design and optimization. However, understanding of how bone surface curvature distributions correlate with bone microstructure and mechanical properties remains limited. This study hypothesized that bone surface curvature distributions could be used to predict the microstructure as well as mechanical properties of trabecular bone. To test the hypothesis, a convolutional neural network (CNN) model was trained and validated to predict the histomorphometric parameters (e.g., BV/TV, BS, Tb.Th, DA, Conn.D, and SMI), geometric parameters (e.g., plate area PA, plate thickness PT, rod length RL, rod diameter RD, plate-to-plate nearest neighbor distance NNDPP, rod-to-rod nearest neighbor distance NNDRR, plate number PN, and rod number RN), as well as the apparent stiffness tensor of trabecular bone using various bone surface curvature distributions, including maximum principal curvature distribution, minimum principal curvature distribution, Gaussian curvature distribution, and mean curvature distribution. The results showed that the surface curvature distribution-based deep learning model achieved high fidelity in predicting the major histomorphometric parameters and geometric parameters as well as the stiffness tenor of trabecular bone, thus supporting the hypothesis of this study. The findings of this study underscore the importance of incorporating bone surface curvature analysis in the design of synthetic bone materials and implants.

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Background: For years, bone mineral density (BMD) has played a key role in assessing bone health, but the trabecular bone score (TBS) is emerging as an equivalent measure. However, BMD alone may not fully measure bone quality or predict osteoporosis risk. To evaluate the usefulness of TBS and BMD in estimating the risk of bone fracture in young women with FHA, this study examined the association between metabolic parameters and bone quality, which was measured using TBS and BMD. Methods: We analyzed the association of metabolic factors with tests assessing bone quality-TBS and BMD. Patients were checked for BMI, measured body fat, and determined serum glucose levels and insulin levels in a 75g glucose load test. Spearman correlation analysis was used. Results: Significant positive correlations were found between BMD and age (p < 0.001) and body fat (p < 0.001), as well as between TBS values and BMI (p < 0.001) and TBS and percent body fat (p < 0.001). Of the variables analyzed in the multivariate analysis, the only independent predictor of higher bone mineral density in the lumbar spine was found to be higher values of the trabecular bone index in the same segment (p < 0.001). Conclusions: The use of TBS provides a simple tool for estimating the risk of bone damage. Ultimately, early screening, diagnosis and treatment of patients with FHA may help prevent osteoporosis and fragility fractures in the long term.

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Estimating chronological age is crucial in forensic identification. The increased application of medical imaging in age analysis has facilitated the development of new quantitative methods for the macroscopic evaluation of bones. This study aimed to determine the association of age-related changes in the trabecular microstructure with chronological age for age estimation in forensic science through different non-invasive imaging techniques. This systematic review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. An electronic search was performed with PubMed/MEDLINE, Scopus, and Cochrane databases as well as with a Google Scholar search. Qualitative synthesis was performed using the Anatomical Quality Assessment tool. A detailed literature search yielded 3467 articles. A total of 14 articles were ultimately included in the study. A narrative approach was employed to synthesize the data. Microcomputed tomography, high-resolution peripheral quantitative computed tomography, and cone beam computed tomography have been used for the quantitative estimation of age. These imaging techniques aid in identifying the trabecular bone microarchitectural parameters for chronological age estimation. Age-related changes in trabecular bone included a decrease in the bone volume fraction, trabecular number, and connectivity density and an increase in trabecular separation. This study also revealed that morphometric indices vary with age and anatomical site. This study is registered with the International Prospective Register of Systematic Reviews (PROSPERO) with the registration number CDRD42023391873.

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The femoral head is one of the most commonly used bones for allografts and biomechanical studies. However, there are few reports on the trabecular bone microarchitectural parameters of freshly harvested trabecular bones. To our knowledge, this is the first study to characterize the microstructure of femoral heads tested immediately after surgery and compare it with the microstructure obtained with conventional freezing. This study aims to investigate whether freezing at -80 °C for 6 weeks affects the trabecular microstructure of freshly harvested bone tissue. This study was divided into two groups: one with freshly harvested human femoral heads and the other with the same human femoral heads frozen at -80 °C for 6 weeks. Each femoral head was scanned using an X-ray microcomputed tomography scanner (µCT) to obtain the microarchitectural parameters, including the bone volume fraction (BV/TV), the mean trabecular thickness (Tb.th), the trabecular separation (Tb.sp), the degree of anisotropy (DA), and the connectivity density (Conn.D). There was no statistically significant difference between the fresh and the frozen groups for any of the parameters measured. This study shows that freezing at -80 °C for 6 weeks does not alter bone microstructure compared with freshly harvested femoral heads tested immediately after surgery.

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For designing trabecular (Tb) bone substitutes suffering from osteoporosis, finite element model (FEM) simulations were conducted on honeycombs (HCs) of 8 × 8 × 1 (2D) and 8 × 8 × 8 (3D) assemblies of cube cellular units consisting of 0.9 mm long Nylon® 66 (PA, Young's modulus E: 2.83 GPa) and polyethylene (PE, E: 1.1 GPa) right square prisms. Osteoporotic damage to the Tb bone was simulated by removing the inner vertical struts (pillars; the number of removed pillars: Δn ≤ 300) and by thinning the strut (thickness, d: 0.4-0.1 mm), while the six facade lattices were kept flawless. Uniform and uniaxial compressive loads on the HCs induced elastic deformation of the struts. The pillars held almost all the load, while the horizontal struts (beams) shared little. E for PA 3D HCs of all d smoothly decreased with Δn. PA 3D HCs of 0.2 mm struts deserved to be the substitutes for Tb bone, while PE 3D HCs of 0.05 mm struts were only for the Tb bone of the poorest bone quality. For the PA 3D HCs, the maximum von Mises stress (σM) first rapidly increased with Δn and showed a break at Δñ50, then gradually approached the yield stress of PA (50 MPa). Moreover, small portions of the stress were transferred from the façade pillars to the adjacent inner beams, especially those near the lost-pillar sites, denoted as X defects. The floor beams of thinner struts associated with the X-defects were lifted, and similar lifting effects in smaller amounts were propagated to the other floors. The 3DHCs of the thicker struts showed no such flexural deformations. The concept of force percolation through the remaining struts was proposed to interpret those mechanical behaviors of the HCs.

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Implant subsidence into the underlying trabecular bone is a common problem in orthopaedic surgeries; however, the ability to pre-operatively predict implant subsidence remains limited. Current state-of-the-art computational models for predicting subsidence have issues addressing this clinical problem, often resulting from the size and complexity of existing subject-specific, image-based finite element (FE) models. The current study aimed to develop a simplified approach to FE modeling of subject-specific trabecular bone indentation resulting from implant penetration. Confined indentation experiments of human trabecular bone with flat- and sharp-tip indenters were simulated using FE analysis. A generalized continuum-level approach using a meshless smoothed particle hydrodynamics (SPH) approach and an isotropic crushable foam (CF) material model was developed for the trabecular bone specimens. Five FE models were generated with CF material parameters calibrated to cadaveric specimens spanning a range of bone mineral densities (BMD). Additionally, an alternative model configuration was developed that included consideration of bone marrow, with bone and marrow material parameters assigned to elements randomly according to bone volume (BV%) measurements of experimental specimens, owing to the non-uniform nature of trabecular bone tissue microstructure. Statistical analysis found significant correlation between the shapes of the numerical and experimental force-displacement curves. FE models accurately captured the bone densification patterns observed experimentally. Inclusion of marrow elements offered improved response prediction of the flat-tip indenter tests. Ultimately, the developed approach demonstrates the ability of a generalizable continuum-level SPH approach to capture bone variability using clinical bone imaging metrics without needing detailed image-based geometries, a significant step towards simplified subject-specific modeling of implant subsidence.

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INTRODUCTION: Bisphosphonates and denosumab increase bone mineral density (BMD) for osteoporosis treatment in patients with aromatase inhibitor-associated bone loss (AIBL). This study aimed to directly compare bisphosphonates with denosumab in treating patients with AIBL and to determine the effect of denosumab on the trabecular bone score (TBS). MATERIALS AND METHODS: Thirty-nine patients with AIBL receiving osteoporosis treatment (21 in the bisphosphonates group and 18 in the denosumab group) were retrospectively evaluated for changes in lumbar spine and femoral BMD, lumbar spine bone quality (assessed by TBS), and blood bone metabolic markers. The Mann-Whitney and Wilcoxon tests were used for statistical evaluation. RESULTS: After 24 months of treatment, the lumbar spine BMD change rate was 5.82 ± 1.10% with bisphosphonates and 10.49 ± 1.20% with denosumab, with the change rate of denosumab significantly increasing over that of bisphosphonates. The change rate in femoral BMD was 2.69 ± 1.16% with bisphosphonates and 2.95 ± 1.26% with denosumab, with no significant difference between the two groups. The rate of decrease in tartrate-resistant acid phosphatase isoform 5b was significantly higher in the denosumab group. The change rate in TBS at 24 months of treatment was 0.53 ± 1.26% in the bisphosphonates group and 1.08 ± 1.33% in the denosumab group, with no significant difference between the two groups. After 24 months, TBS remained stable. CONCLUSION: Both bisphosphonates and denosumab may increase BMD, improve bone metabolism, and inhibit bone quality loss in patients with AIBL.

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Introduction There has been no study on bone structural properties in postmenopausal women with rheumatoid arthritis (RA) in Japan. This study investigated bone mineral density (BMD) and bone structural properties in Japanese postmenopausal women with RA. Methods The study had a cross-sectional design and included 119 postmenopausal women aged 50-80 years with RA symptoms for more than five years. BMD, trabecular bone score (TBS), and results of hip structure analysis (HSA) were measured on dual-energy X-ray absorptiometry scans. The control group consisted of 288 women aged 50-80 years without RA. The RA group and control group using bisphosphonates were compared after propensity score matching for age, body mass index, and fracture history. Women in the RA group were also compared according to the use of glucocorticoids (GCs). Results After the propensity matching score, there were no other significant differences in BMD, TBS, and HSA parameters between the RA group and the control group. In the RA group, the TBS was lower in patients on GCs than those not on GCs (1.272 vs 1.313, p=0.008). There were no other significant differences in BMD and HSA parameters between patients in the RA group according to the use of GCs. Conclusion Although there were no differences in BMD, the TBS was lower in patients on GCs than those not on GCs in the RA group. It is thus important for physicians who administer GCs to treat patients with RA to be aware of not only BMD but also TBS.

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Background: The longitudinal changes in hip-bone microstructures and estimated bone strength in dialysis patients, and the impact of chronic kidney disease-mineral and bone disorder (CKD-MBD) biomarkers on these changes, remain insufficiently explored. Methods: This retrospective study examined changes in cortical and trabecular bone compartments and estimated bone-strength indices, obtained by using 3D-SHAPER software, in the hip regions of 276 dialysis patients over up to 2.5 years. We used multivariate mixed models to investigate the associations between time-dependent CKD-MBD biomarkers and bone health metrics. Results: There was a significant decrease in areal bone mineral density (aBMD), integral volumetric BMD (vBMD), trabecular vBMD, cortical thickness and cortical surface BMD (sBMD). Similar deteriorations were found in estimated bone-strength indices [cross-sectional area (CSA), cross-sectional moment of inertia (CSMI), section modulus (SM) and buckling ratio]. Neither serum calcium nor phosphate levels were significantly associated with changes in three-dimensional parameters or estimated bone-strength indices. In contrast, serum alkaline phosphatase levels showed a significant inverse correlation with aBMD and CSA. The intact-parathyroid hormone (i-PTH) was significantly inversely correlated with aBMD, integral vBMD, trabecular vBMD, cortical thickness, cortical vBMD, CSA, CSMI and SM. When applying the KDIGO criteria as a sensitivity analysis, the higher PTH group had significant negative associations with aBMD, integral vBMD, cortical vBMD, cortical thickness and cortical sBMD. Notably, the lower PTH group showed a positive significant correlation with integral vBMD and trabecular vBMD. Conclusions: Elevated PTH, not low PTH, was associated with deterioration of hip-bone microstructures. Better management of PTH levels may play a crucial role in the hip-bone microstructure in dialysis patients.

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(1) Background and aim: The effects of functional therapies on dentoalveolar and skeletal structures have been investigated in orthodontics for many years. The aim of this retrospective study was to evaluate the changes caused by fixed and removable functional therapy in the mandibular anterior trabecular structures using fractal dimension (FD) analysis. (2) Methods: A total of 60 patients with skeletal and dental class II malocclusion were included in the study and three groups were formed: the untreated control group (CG), the Forsus fatigue-resistant device group (FFRDG), and the Monoblock group (MBG). Bone areas of interest determined in the buccoapical of the mandibular incisors and the symphysis in the lateral cephalometric radiographs taken before (T0) and after (T1) functional therapy were evaluated using FD analysis. The relationship between the FD and IMPA (Incisor Mandibular Plane Angle) angles was evaluated. Parametric and nonparametric tests were used in statistical analysis according to normality distribution. The statistical significance level was determined as p < 0.05. (3) Results: There was no statistically significant difference between the FD values of all groups at T0 (p > 0.05). At T1, buccoapical FD values were significantly lower in FFRDG and MBG compared to the control group (p < 0.05), while symphyseal FD values were not found to be significant (p > 0.05). The IMPA angle was significantly lower in the FFRDG and MBG than in the control group at T0, while it was higher at T1 (p < 0.05). While a significant negative correlation was observed between the IMPA angle and buccoapical FD values in both FFRDG and MBG (p < 0.05), it was not observed with the symphysis FD values (p > 0.05). (4) Conclusions: Trabecular changes caused by functional therapy in the mandibular anterior bone can be evaluated on lateral cephalometric radiographs with FD analysis. It was concluded that orthodontists should ensure controlled changes in the IMPA angle during functional therapy, especially for the decreases in FDs seen in the buccoapical alveolar region due to the forward movement of the mandibular incisors.

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This study investigates the biomechanics of type 2 diabetic bone fragility through a multiscale experimental strategy that considers structural, mechanical, and compositional components of ex vivo human trabecular and cortical bone. Human tissue samples were obtained from the femoral heads of patients undergoing total hip replacement. Mechanical testing was carried out on isolated trabecular cores using monotonic and cyclic compression loading and nanoindentation experiments, with bone microdamage analysed using micro-computed tomography (CT) imaging. Bone composition was evaluated using Raman spectroscopy, high-performance liquid chromatography, and fluorometric spectroscopy. It was found that human type 2 diabetic bone had altered mechanical, compositional, and morphological properties compared to non-type 2 diabetic bone. High-resolution micro-CT imaging showed that cores taken from the central trabecular region of the femoral head had higher bone mineral density (BMD), bone volume, trabecular thickness, and reduced trabecular separation. Type 2 diabetic bone also had enhanced macro-mechanical compressive properties under mechanical loading compared to non-diabetic controls, with significantly higher apparent modulus, yield stress, and pre-yield toughness evident, even when properties were normalised against the bone volume. Using nanoindentation, there were no significant differences in the tissue-level mechanical properties of cortical or trabecular bone in type 2 diabetic samples compared to controls. Through compositional analysis, higher levels of furosine were found in type 2 diabetic trabecular bone, and an increase in both furosine and carboxymethyl-lysine (an advanced glycation end-product) was found in cortical bone. Raman spectroscopy showed that type 2 diabetic bone had a higher mineral-to-matrix ratio, carbonate substitution, and reduced crystallinity compared to the controls. Together, this study shows that type 2 diabetes leads to distinct changes in both organic and mineral phases of the bone tissue matrix, but these changes did not coincide with any reduction in the micro- or macro-mechanical properties of the tissue under monotonic or cyclic loading.

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Chronic obstructive pulmonary disease (COPD) is a disease characterized by chronic respiratory symptoms due to inflammatory and destructive changes of the lung leading to progressive airflow obstruction. Fragility fractures associated with osteoporosis are among major comorbidities and have significant impacts on quality of life and prognosis of patients with COPD. Evidence suggests that both decreased bone mineral density (BMD) and impaired bone quality contribute to bone fragility and resultant fractures in COPD. Although various clinical risk factors of osteoporosis have been described, mechanisms of COPD-associated osteoporosis are still largely unknown. In addition, its specific treatment has not been established, either. Previous studies have suggested involvement of low BMI and sarcopenia in the pathogenesis of COPD-associated osteoporosis. In this narrative review, we will propose critical roles of vitamin D deficiency and inflammation, both of which are often present in COPD and may underlie the development of osteosarcopenia and impaired bone quality, ultimately causing fractures in COPD patients.

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Osteoporosis is the most prevalent skeletal disorder, a condition that is associated with significant social and healthcare burden. In the elderly, osteoporosis is commonly associated with sarcopenia, further increasing the risk of fracture. Several imaging techniques are available for a non-invasive evaluation of osteoporosis and sarcopenia. This review focuses on dual-energy X-ray absorptiometry (DXA), as this technique offers the possibility to evaluate bone mineral density and body composition parameters with good precision and accuracy. DXA is also able to evaluate the amount of aortic calcification for cardiovascular risk estimation. Additionally, new DXA-based parameters have been developed in recent years to further refine fracture risk estimation, such as the Trabecular Bone Score and the Bone Strain Index. Finally, we describe the recent advances of a newly developed ultrasound-based technology known as Radiofrequency Echographic Multi-Spectrometry, which represent the latest non-ionizing approach for osteoporosis evaluation at central sites.

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Pheochromocytoma and paraganglioma (PPGL) have been associated with low bone mineral density (BMD) due to excess sympathetic system stimulation. Our study revealed low BMD and TBS (trabecular bone score) in cases compared to matched controls. Plasma-free nor-metanephrine and hypertension duration found to be most consistent predictive factors. PURPOSE: Pheochromocytoma and paraganglioma (PPGL) have been associated with low bone mineral density (BMD) and increased fracture risks. Sympathetic nervous system stimulation has been shown to increase bone resorption and decrease bone formation via ß2 receptors. Chronic inflammation and increased cytokine production add to more bone loss. TBS (trabecular bone score) is an established surrogate marker for bone histomorphometry. BMD and TBS data in pheochromocytoma and PPGL are scarce. The aim was to assess the BMD and TBS in pheochromocytoma and PPGL and look for clinical and biochemical predictors. METHODS: This case-control study had sample size of 58 (29 cases and controls each). BMI-, age-, and sex-matched controls were taken for comparison. Both cases and controls had undergone DXA scan and BMD {Z-scores and bone mineral concentration (BMC) in g/cm2} and TBS were analyzed. Detailed clinical histories and relevant biochemistry values were noted. RESULTS: The mean age of our case population was 29.5 ± 9.4 years with a mean age of HTN onset at 26.86 ± 6.6 years. Lumbar spine BMC (0.86 ± 0.14 vs 0.96 ± 0.15; p = 0.036), femoral neck Z-score (- 1.23 ± 1.07 vs - 0.75 ± 0.97; p = 0.003), and whole body BMC (0.91 ± 0.14 vs 1.07 ± 0.11; p = 0.000) were significantly low in cases compared to controls. Similarly, TBS was significantly lower in cases compared to controls (1.306 ± 0.113 vs 1.376 ± 0.083; p = 0.001). CONCLUSION: This study establishes both low bone mass and poor bone quality in an Indian pheochromocytoma and PPGL patient's cohort. Plasma-free nor-metanephrine and duration of hypertension were found to be most consistent predictive factors in multivariate regression analysis.