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We investigated the effectiveness of a resistance training (RT) protocol with lower volume and lower load in the body recomposition of postmenopausal women, and to determine whether changes in body recomposition induced by RT would be associated with changes in physical performance, independently of confounding factors. Participants were randomly assigned to one of three groups: I) Single set-high load (SSHL, n = 14, 1 set of 8 to 12 maximum repetitions), II) Single set-low load (SSLL, n = 15, 1 set of 25 to 30 maximum repetitions), and III) Multiple sets-high load (MSHL, n = 14, 3–6 sets of 8 to 12 maximum repetitions). The study extended over a duration of 27 weeks, encompassing 24 weeks of RT. We assessed body composition using dual-energy X-ray absorptiometry, physical performance using the Timed Up and Go and sit and stand tests, and muscle strength using the one-repetition maximum (1RM) test. We quantified body recomposition using a composite z score calculated as follows: (appendicular lean mass % delta z score) + (− 1 × fat mass delta % z score) / 2. Results showed significant improvements in physical performance (P < 0.001), significant reductions in visceral adipose tissue, total fat mass, and % fat (P = 0.003, P = 0.042, and P < 0.001, respectively), and increases in muscle mass and strength (P < 0.001), regardless of group assignment. Notably, the higher load groups (SSHL and MSHL) had significantly greater body recomposition compared to the lower load group (SSLL), particularly after adjusting for age, physical activity, and sitting time (P = 0.028). Therefore, the higher load of RT is a critical factor in the body recomposition of postmenopausal women. Furthermore, the positive effects of body recomposition induced by RT extend to physical performance and muscle strength. [ABSTRACT FROM AUTHOR]

This study aimed to investigate seasonal heat acclimatization in active adolescents following summer. Fifteen (5 females) active adolescents (14.6 ± 1.0 y) completed a 45-min heat response test (HRT) walking at 60% $\dot {\rm V}$ V ˙ O2peak in 40°C and 30% relative humidity before and after summer (i.e. November 2022 and March 2023). During the HRT, gastro-intestinal temperature (Tgi), skin temperature (Tsk), heart rate, local sweat rate (LSR) and whole-body sweat loss (WBSL) were recorded. Carbon monoxide rebreathing and dual-energy X-ray absorptiometry scans determined resting hematological measures and body composition. Participants completed physical activity (PA) diaries and wore an accelerometer for two one-week periods (pre- and post-summer). Daytime wet-bulb globe temperature (WBGT) was calculated for each summer day. Data are presented as posterior mean and 90% credible intervals. Participants reported 7 ± 4 h·wk−1 of outdoor PA, and daytime WBGT was 21.2 ± 4.6°C. Following summer, resting Tgi and heart rate were reduced by 0.2°C [−0.3, −0.1; probability of direction = 99%] and 7 beats·min−1 [−10, −3; 100%], respectively. During the HRT, there was an earlier onset of sweating (−0.2°C [−0.3, −0.0; 98%]), an attenuated rise of Tgi (0.2°C [−0.5, 0.0; 92%]) and mean Tsk changed by −0.2°C [−0.5, 0.1; 86%]. There was minimal evidence for heat adaptations in LSR or WBSL, hematological parameters or perceptual measures. This is the first study to demonstrate seasonal heat adaptations in active adolescents. Reductions in resting Tgi and exercising Tsk and a lower Tgi at the onset of sweating were associated with a smaller rise in Tgi during the HRT following summer. [ABSTRACT FROM AUTHOR]

Aim: Higher adiposity and increased risk of cardiovascular diseases have been reported in juvenile idiopathic arthritis (JIA), but body composition measurements have produced inconsistent results. This controlled cross‐sectional study assessed body composition with two methods to evaluate adiposity in children with JIA. Methods: We measured body composition by dual‐ energy X‐ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA) from 79 JIA‐patients in two Finish university hospitals in 2017–2019. Their age‐ and sex‐matched controls (n = 79) were selected from the Physical Activity and Nutrition in Children‐ study and through National Registry. Results: Body fat percentage measured by BIA was higher (mean, SD) in patients compared to controls (23.1 ± 9.3% vs. 20.1 ± 7.5%, p = 0.047). Also, using DXA, there was a tendency of higher body fat percentage in patients (27.1 ± 9.1% vs. 24.6 ± 8.6, p = 0.106). BIA and DXA showed strong correlation (r from 0.810 to 0.977) in all body composition variables. Conclusion: Increased adiposity was observed in patients with JIA. Evaluation of body composition should be included in the multidisciplinary care of JIA to reduce the possible risk of cardiovascular diseases in adulthood. BIA could be a useful tool for assessing body composition due to its clinical availability and safety. [ABSTRACT FROM AUTHOR]

Sacral insufficiency fractures are known to occur primarily in older women without adequate trauma. While an association with low bone mineral density (ie, osteoporosis) has been reported, more detailed information on local bone quality properties in affected patients is not available. In the present study, core biopsies were obtained from the S1 sacral ala in patients with a bilateral sacral insufficiency fracture (type IV according to the fragility fractures of the pelvis classification) who required surgical stabilization. Dual energy X-ray absorptiometry (DXA) and laboratory bone metabolism analyses were performed. For comparison, control biopsies were acquired from skeletally intact age- and sex-matched donors during autopsy. A total of 31 biopsies (fracture: n = 19; control: n = 12) were evaluated by micro-computed tomography, histomorphometry on undecalcified sections, and quantitative backscattered electron imaging (qBEI). DXA measurements showed mean T-scores in the range of osteoporosis in the fracture cohort (T-scoremin −2.6 ± 0.8). Biochemical analysis of bone metabolism parameters revealed high serum alkaline phosphatase and urinary deoxypyridinoline/creatinine levels. In the biopsies, a loss of trabecular microstructure along with increased osteoid values were detected in the fracture patients compared with controls (osteoid volume per bone volume 5.9 ± 3.5 vs. 0.9 ± 0.5%, p <.001). We also found evidence of microfractures with chronic healing processes (ie, microcallus) as well as pronounced hypomineralization in the biopsies of the fracture cohort compared with the controls as evidenced by lower CaMean measured by qBEI (22.5 ± 1.6 vs. 24.2 ± 0.5 wt%, p =.003). In conclusion, this high-resolution biopsy study provides evidence of local hypomineralization in patients with sacral insufficiency fractures, pointing to reduced fracture resistance but also a distinct phenotype other than the predominant loss of trabeculae as in postmenopausal osteoporosis. Our data highlight the importance of therapies that promote bone mineralization to optimally treat and prevent sacral insufficiency fractures. Lay Summary: Sacral insufficiency fracture is a type of fracture occurring particularly in older women after low-energy trauma or repetitive physiologic loads. While it is suspected that diminished bone quality plays a causal role, it has not yet been investigated which aspects of bone quality are affected by means of a biopsy study. Here, the microstructure, turnover, and mineralization were investigated in biopsies obtained from patients with bilateral sacral insufficiency fractures during surgery. Compared with a control group of skeletally intact donors, the most striking finding in the biopsies of the fracture patients was impaired bone mineralization. Namely, high proportions of unmineralized osteoid and low bone matrix mineralization were detected by undecalcified histology and quantitative backscattered electron imaging, respectively. In addition, the trabeculae of some biopsies showed signs of chronic microfracture. Collectively, these results not only show that sacral insufficiency fractures belong to a spectrum different from classical osteoporosis-related fractures but also underline the importance of therapies that promote bone mineralization, for instance vitamin D and calcium supplementation. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the associations between thyroid hormone (TH) levels, central sensitivity to THs, and body composition in overweight and obese patients with euthyroid type 2 diabetes mellitus (T2DM). Methods: This cross-sectional study included 1215 euthyroid T2DM patients (721 men and 494 women) aged 20– 80 years. The thyroid hormone sensitivity indices included the thyroid feedback quartile-based index (TFQI), thyrotroph T3 resistance index (TT3RI), thyrotroph T4 resistance index (TT4RI), and thyroid-stimulating hormone index (TSHI). The appendicular fat ratio, trunk fat ratio, android fat ratio, gynoid fat ratio, and appendicular skeletal muscle mass (ASM) were measured via dual-energy X-ray absorptiometry. Results: The data revealed a greater proportion of subjects with impaired central sensitivity to THs in the obese group. TFQIFT4 and TFQIFT3 levels were positively correlated with the upper limb fat ratio, lower limb fat ratio, gynoid fat ratio, and total fat ratio. TSHI was positively correlated with body mass index (BMI), upper limb fat ratio, lower limb fat ratio, trunk fat ratio, android fat ratio, gynoid fat ratio, total fat ratio, and appendicular skeletal muscle mass index (ASMI) in women. In men, TSHI was only positively correlated with upper limb fat ratio, lower limb fat ratio, and total fat ratio. Logistic regression analysis indicated that TT3RI and TFQIFT3 were independently and positively associated with central obesity and low muscle mass in overweight and obese men. No significant differences were found among the women. Conclusion: THs central sensitivity is related to the body composition of euthyroid T2DM patients. Specifically, high levels of TT3RI and TFQIFT3 are associated with central obesity and low muscle mass in T2DM men with overweight and obesity. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Context: Dual-energy x-ray absorptiometry (DXA) is widely known for its utility in diagnosing a patient with osteopenia or osteoporosis; however, its utility in evaluation of body composition and potential athletic performance was previously routinely overlooked. In recent years, athletic programs have begun employing this equipment during athlete screening. However, it is currently unknown how athletic programs are utilizing this information to guide an athlete's training and health. Objective: To explore the literature to identify what is known regarding sports performance and athlete health based on body composition recordings. Data Sources: PubMed and Google Scholar databases were searched for this brief review. Study Selection: A focus was placed on articles within the past 10 years that discussed DXA protocols within athletic populations; 14 articles were included in this brief literature review. Study Design: Brief literature review. Level of Evidence: Level 5. Data Extraction: One member of the research team searched the literature and retrieved articles with the purpose of analyzing and/or explaining DXA imaging in body composition analysis of active persons (primarily athletes). Results: Quality assurance scans with a phantom calibration block as well as athlete prescreening condition and activity standardization was routinely recommended. However, only 1 study reported a specific DXA protocol for athletes, and only 1 study described guidelines for how to report DXA results in athletic populations, suggesting it is plausible yet difficult due to the small changes detectable. Conclusion: Due to the limited literature as well as a lack of reference values for specific athletic populations, the authors of this review recommend using the current Nana et al (Int J Sport Nutr Exerc Metab 2015;25:198-215) DXA protocol for performing DXA scans in the athletic population as well as current Hind et al (J Clin Densitom 2018;21:429-443) guidelines for distributing the information. [ABSTRACT FROM AUTHOR]

Background/Objectives: In children, an association exists between muscle and bone, as well as between physical activity and osteogenesis. Impact loading is a factor in increasing bone accrual during growth. In this work, we explored the muscle–bone association in girls exposed to long-term physical activity at different levels of impact loading. Methods: Four groups of girls aged 7–16 were considered. The curricular (C; n = 22) group only had curricular physical activity at school (2 h/w). In addition to curricular physical activity, the girls in the dance (D; n = 21), gymnastics at lower training (GL; n = 14), and gymnastics at higher training (GH; n = 20) groups had 2 h/w, 4 h/w, and 4 h/w < training ≤ 12 h/w additional physical activity, respectively, for at least one year. A visual analysis estimated the respective amounts of impact-loading activity. The bone mineral content (BMC), areal bone mineral density (aBMD), and fat-free soft tissue mass (FFSTM) were assessed with dual-energy X-ray absorptiometry. Results: The results showed that, after adjusting for several confounders, statistically significant correlations were present between muscle mass and several bone mineral variables. A regression analysis confirmed the correlation in the data, and showed the marginal role of other body composition variables and physical activity for predicting BMC and BMD. Conclusion: Skeletal muscle mass is a major determinant of the BMC and BMD of the TBLH, as well as of the Appendicular level, in girls exposed to different amounts of long-term impact-loading physical activity. [ABSTRACT FROM AUTHOR]

Osteoporosis, a skeletal disorder, is expected to affect 60% of women aged over 50 years. Dual-energy X-ray absorptiometry (DXA) scans, the current gold standard, are typically used post-fracture, highlighting the need for early detection tools. Panoramic radiographs (PRs), common in annual dental evaluations, have been explored for osteoporosis detection using deep learning, but methodological flaws have cast doubt on otherwise optimistic results. This study aims to develop a robust artificial intelligence (AI) application for accurate osteoporosis identification in PRs, contributing to early and reliable diagnostics. A total of 250 PRs from three groups (A: osteoporosis group, B: non-osteoporosis group matching A in age and gender, C: non-osteoporosis group differing from A in age and gender) were cropped to the mental foramen region. A pretrained convolutional neural network (CNN) classifier was used for training, testing, and validation with a random split of the dataset into subsets (A vs. B, A vs. C). Detection accuracy and area under the curve (AUC) were calculated. The method achieved an F1 score of 0.74 and an AUC of 0.8401 (A vs. B). For young patients (A vs. C), it performed with 98% accuracy and an AUC of 0.9812. This study presents a proof-of-concept algorithm, demonstrating the potential of deep learning to identify osteoporosis in dental radiographs. It also highlights the importance of methodological rigor, as not all optimistic results are credible. [ABSTRACT FROM AUTHOR]

Bioelectrical impedance (BIA) and ultrasound (US) have become popular for estimating body fat percentage (BF%) due to their low cost and clinical convenience. However, the agreement of these devices with the gold-standard method still requires investigation. The aim was to analyze the agreement between a gold-standard %BF assessment method with BIA and US devices. Twenty-three men (aged 30.1 ± 7.7 years, weighing 82.5 ± 14.9 kg, 1.77 ± 0.05 m tall) underwent dual-energy X-ray absorptiometry (DXA), BIA (tetrapolar) and US (three-site method) %BF assessments. Pearson and concordance correlations were analyzed. A T-test was used to compare the means of the methods, and Bland–Altman plots analyzed agreement and proportional bias. Alpha was set at <0.05. The Pearson coefficients of BIA and US with DXA were high (BIA = 0.94; US = 0.89; both p < 0.001). The concordance coefficient was high for BIA (0.80) and moderate for US (0.49). The BF% measured by BIA (24.5 ± 7.5) and US (19.4 ± 7.0) was on average 4.4% and 9.6% lower than DXA (29.0 + 8.5%), respectively (p < 0.001). Lower and upper agreement limits between DXA and BIA were −1.45 and 10.31, while between DXA and US, they were 2.01 and 17.14, respectively. There was a tendency of both BIA (p = 0.09) and US (p = 0.057) to present proportional bias and underestimate BF%. Despite the correlation, the mean differences between the methods were significant, and the agreement limits were very wide. This indicates that BIA and US, as measured in this study, have limited potential to accurately measure %BF compared to DXA, especially in individuals with higher body fat. [ABSTRACT FROM AUTHOR]

Background/Objectives: The aim of this study was to evaluate the effects of lifelong team handball/football training on regional bone health and body composition in elderly women. Methods: Seventeen elderly women team handball/football players (65.9 ± 5.7 years) and twenty-one untrained age-matched women (controls) (67.7 ± 5.1 years) participated. Whole-body and regional dual-energy X-ray absorptiometry scans of arms, legs, and lower spine (L1–L4) were performed. Results: We observed 8% and 9% higher bone mineral density (BMD) and bone mineral content (BMC), respectively, at the whole-body level and in the legs and 11.5% higher BMC in the legs in team handball/football players compared to untrained age-matched controls (p < 0.05). Higher total and leg lean body mass (p < 0.05), along with lower total body fat percentage (p < 0.05) and higher T- and Z-scores, markers of fragility risk fracture (0.294 ± 1.461 vs. −0.538 ± 1.031; 1.447 ± 1.278 vs. 0.724 ± 0.823, respectively), were also found in team handball/football players compared to controls (p < 0.05). No significant differences in nutritional habits were observed between groups. Conclusions: Our study suggest that the beneficial effects of lifetime handball/football practice on bone preservation in elderly women occur independently from nutritional intake, which emphasize the potential role of team sports in osteoporosis prevention. Future studies should focus on the cofounding factors and causative mechanisms mediated by team sport practice in osteoporosis prevention. [ABSTRACT FROM AUTHOR]

Objectives We aimed to study trabecular bone score (TBS) association with disease parameters and vertebral fractures (VFs) in patients with axial spondyloarthritis. Methods Patients diagnosed with axial spondyloarthritis were included in this cross-sectional study. Dual-energy X-ray absorptiometry was used to measure BMD in the lumbar spine and TBS. Low TBS was defined as ≤1.31. The association between TBS and disease parameters including Ankylosing Spondylitis Disease Activity Score (ASDAS), BASDAI, BASFI and BASMI was studied using logistic regressions. Results Our study included 56 patients, with a mean age of 38.9 ± 13.5 years and a mean disease duration of 12.7 ± 7.7 years. Patients with low TBS were significantly older and had higher waist circumference and body mass index. These patients also showed greater clinical activity, as evidenced by higher ASDAS-CRP, BASFI and BASMI scores (P  < 0.05). In multivariate logistic regression, low TBS was associated with all disease parameters, except for BASMI: BASDAI (OR [95% CI] = 3.68 [1.48–9.19], P  = 0.005), ASDAS-CRP (OR [95% CI] = 2.92 [1.20–7.10], P  = 0.018), BASFI (OR [95% CI] = 1.04 [1.01–1.08], P  = 0.018), BASMI (OR [95% CI] = 1.36 [0.99–1.87], P  = 0.062). However, no association was observed between TBS and VFs. Conclusion TBS was associated with active spondyloarthritis, suggesting increased bone fragility in these patients. However, TBS failed to demonstrate an association with VFs. [ABSTRACT FROM AUTHOR]

Copyright of SPORMETRE: The Journal of Physical Education & Sport Sciences / Beden Eğitimi ve Spor Bilimleri Dergisi is the property of SPORMETRE: The Journal of Physical Education & Sport Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Previous research shows conflicting views on the relationship between obesity and osteoporosis, partly due to variations in obesity classification and the nonlinear nature of these relationships. This study investigated the association between adiposity indices and osteoporosis, diagnosed using dual-energy X-ray absorptiometry (DXA), employing nonlinear models and offering optimal thresholds to prevent further bone mineral density decline. Methods: In 2019, a prospective study enrolled males over 50 years and postmenopausal women. Anthropometric measurements, blood biochemistry, and osteoporosis measured by DXA were collected. Associations between adiposity indices and osteoporosis were analyzed using a generalized additive model and segmented regression model. Results: The study included 872 women and 1321 men. Indices such as abdominal volume index (AVI), visceral adiposity index (VAI), waist circumference (WC), hip circumference, body mass index (BMI), waist-to-hip ratio, and waist-to-height ratio (WHtR) were inversely associated with osteoporosis. In women, the relationship between the risk of osteoporosis and the adiposity indices was U-shaped, with thresholds of WC = 94 cm, AVI = 17.67 cm2, BMI = 25.74 kg/m2, VAI = 4.29, and WHtR = 0.61, considering changes in bone mineral density. Conversely, men exhibited a linear patterns for the inverse association. Conclusion: The impact of obesity and adiposity on osteoporosis varies significantly between women and men. In postmenopausal women, the relationship is nonlinear (U-shaped), with both very low and very high adiposity linked to higher osteoporosis risk. In men over 50, the relationship is linear, with higher adiposity associated with lower osteoporosis risk. The study suggests that maintaining specific levels of adiposity could help prevent osteoporosis in postmenopausal women. [ABSTRACT FROM AUTHOR]

Context Surrogate measures of childhood and adolescent obesity have impaired the understanding of the relationship of body composition with insulin resistance in the young population. Objective We aim to examine the longitudinal associations of directly measured total fat mass, trunk fat mass, and lean mass with the risk of hyperglycemia, hyperinsulinemia, and insulin resistance from ages 15 to 24 years, the mediation path through which lipids and inflammation influence insulin resistance, and whether increased fat mass temporally precede insulin resistance. Methods We studied 3160 adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC), UK birth cohort, who had complete dual-energy x-ray absorptiometry measure and fasting blood samples at age 15 years and repeated measures at ages 17- and 24-years clinic visit. Fasting glucose greater than 6.1 mmol/L, insulin greater than 11.78 mU/L, and homeostatic model assessment for insulin resistance (HOMA-IR) greater than or equal to the 75th percentile were categorized as hyperglycemia, hyperinsulinemia, and high insulin resistance, respectively. Longitudinal associations were examined with generalized logit-mixed-effect models, while mediation and temporal path analyses were examined using structural equation models, adjusting for cardiometabolic and lifestyle factors. Results Among 3160 participants (51% female), fat mass and lean mass increased linearly both in males and females, while glucose, insulin, and HOMA-IR had a U-shaped course from age 15 through 24 years. After full adjustment, each 1-kg cumulative increase in total fat mass (odds ratio 1.12 [95% CI, 1.11-1.13]) and trunk fat mass (1.21 [1.19-1.23]) from ages 15 through 24 years were associated with a progressively worsening risk of high insulin resistance as well as hyperglycemia and hyperinsulinemia. The association of increased total fat mass with increased insulin resistance was partly mediated by triglycerides (9% mediation). In the temporal path analysis, higher total fat mass at age 15 years was associated with higher insulin resistance at age 17 years, but not vice versa. Higher total fat mass at age 17 years was bidirectionally associated with higher insulin resistance at 24 years. Conclusion Mid-adolescence may be an optimal time for interrupting the worsening fat mass–insulin resistance pathologic cycle and attenuating the risk of progressively worsening metabolic dysfunction before young adulthood. [ABSTRACT FROM AUTHOR]

Abstract Cardiovascular disease (CVD) is a major chronic disease worldwide and its risk factors have long been investigating in epidemiological studies. Our study aims to develop a body composition-based risk score and integrate it into the Framingham Risk Score (FRS) to improve CVD prediction among well-functioning older adults. We included 1882 older adults from the Health, Aging and Body Composition (Health ABC) study to screen body composition variables obtained from the Dual-energy X-ray absorptiometry (DXA). Three models were developed and compared: the 4-DXA model, the refit FRS, and the refit FRS plus 4-DXA model. C-statistics were 0.62 (95% CI: 0.59, 0.65) for the refit FRS, 0.58 (95% CI: 0.55, 0.61) for the 4-DXA model, and 0.63 (95% CI: 0.60, 0.66) for the refit FRS plus 4-DXA model. Compared to the refit FRS, the refit FRS plus 4-DXA model slightly improved CVD outcome prediction as the discrimination slope, net reclassification index, and the integrated discrimination index were 0.053 (95% CI: 0.041, 0.066), 0.098 (95% CI = – 0.0033, 0.20) and 0.013 (95% CI: 0.0069–0.019). This study provides a model for more accurate risk stratification and draws more attention on DXA-based indices in the clinical setting. It also encourages further research in validating the developed risk score in more diverse population and in investigating a broader range of CVD risk factors.

Abstract We aimed to investigate the efficacy of romosozumab treatment compared with that of denosumab in especially male osteoporosis patients. This retrospective cohort study included 174 Japanese male patients receiving either denosumab or romosozumab for 12 months. Propensity score matching extracted 50 patients per treatment group for standardization of group characteristics. The endpoints include the rate of change in the bone mineral density (BMD) of the lumbar spine, total hip, and femoral neck after 12 months of treatment as well as the changes in serum bone metabolism markers. The mean 12-month percentage increase in the lumbar spine BMD from baseline was significantly greater with romosozumab (13.0% ±1.7%) than with denosumab (4.5%±0.6%) (P

Abstract Background The distribution of fat and muscle mass in different regions of the body can reflect different pathways to mortality in individuals with diabetes. Therefore, we investigated the associations between whole‐body and regional body fat and muscle mass with cardiovascular disease (CVD) and non‐CVD mortality in type 2 diabetes (T2D). Methods Within the National Health and Nutrition Examination Survey 1999–2006, 1417 adults aged ≥50 years with T2D were selected. Dual‐energy X‐ray absorptiometry was used to derive whole‐body, trunk, arm, and leg fat mass and muscle mass indices (FMI and MMI). Mortality data until 31 December 2019 were retrieved from the National Death Index. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated from Cox proportional hazard models. Results A total of 1417 participants were included in this study (weighted mean age [standard error]: 63.7 [0.3] years; 50.5% female). Over a median follow‐up of 13.6 years, 797 deaths were recorded (371 CVD‐related and 426 non‐CVD deaths). Higher FMI in the arm was associated with increased risk of non‐CVD mortality (fourth quartile [Q4] vs. first quartile [Q1]: HR 1.82 [95% CI 1.13–2.94]), whereas higher FMI in the trunk or leg was not significantly associated with CVD or non‐CVD mortality. Conversely, higher arm MMI was associated with a lower risk of both CVD (Q4 vs. Q1: HR 0.51 [95% CI 0.33–0.81]) and non‐CVD (Q4 vs. Q1: HR 0.56 [95% CI 0.33–0.94]) mortality. There was a significant interaction between smoking status and arm FMI on non‐CVD mortality (P for interaction = 0.007). Higher arm FMI was associated with a higher risk of non‐CVD mortality among current or former smokers (Q4 vs. Q1: HR 2.67 [95% CI 1.46–4.88]) but not non‐smokers (Q4 vs. Q1: HR 0.85 [95% CI 0.49–1.47]). Conclusions Fat mass and muscle mass, especially in the arm, are differently associated with CVD and non‐CVD mortality in people with T2D. Our findings underscore the predictive value of body compositions in the arm in forecasting mortality among older adults with T2D.

Abstract Background Sarcopenia is an important indicator of ill health and is linked to increased mortality and a reduced quality of life. Age‐associated muscle mass indices provide a critical tool to help understand the development of sarcopenia. This study aimed to develop sex‐ and age‐specific percentiles for muscle mass indices in a Chinese population and to compare those indices with those from other ethnicities using the National Health and Nutrition Examination Survey (NHANES) data. Methods Whole‐body and regional muscle mass was measured by dual‐energy X‐ray absorptiometry (DXA) in participants of the China Body Composition Life‐course (BCL) study (17 203 healthy Chinese aged 3–60 years, male 48.9%) and NHANES (12 663 healthy Americans aged 8–59 years, male 50.4%). Age‐ and sex‐specific percentile curves were generated for whole‐body muscle mass and appendicular skeletal muscle mass using the Generalized Additive Model for Location Scale and Shape statistical method. Results Values of upper and lower muscle mass across ages had three periods: an increase from age 3 to a peak at age 25 in males (with the 5th and 95th values of 41.5 and 66.4 kg, respectively) and age 23 in females (with the 5th and 95th values of 28.4 and 45.1 kg, respectively), a plateau through midlife (30s–50s) and then a decline after their early 50s. The age at which muscle mass began to decline was 52 years in men with the 5th and 95th percentile values of 43.5 and 64.6 kg, and 51 years in women with the 5th and 95th percentile values of 31.6 and 46.9 kg. Appendicular skeletal muscle mass decreased earlier than whole body muscle mass, especially leg skeletal muscle mass, which decreased slightly after age 49 years in both sexes. In comparison with their US counterparts in the NHANES, the Chinese participants had lower muscle mass indices (all P

Background Anthropometry and body mass index (BMI) do not assess body composition or its distribution in older adults; thus, individuals may have different fat percentages but similar BMI values. The body adiposity index (BAI) was recently proposed as a feasible and inexpensive method for estimating the percentage of body fat based on measurements of hip circumference and height. The present study evaluated whether BAI and BMI are useful alternatives to dual-energy X-ray absorptiometry (DXA), which is rarely used in clinical practice, for predicting body fat in independent long-lived older adults. Methods In this cross-sectional study, we used DXA to calculate the percentage of body fat, which was compared with BAI and BMI values. We performed Pearson correlation analyses and used Cronbach’s alpha, described by Bland and Altman, to compare the reliability between the indexes. Results Among 157 evaluated individuals (73.2% women, mean age 87±3.57 years), men had a lower percentage of total fat, as assessed by DXA, and lower BAI indices than women. The correlation between BAI and DXA was moderate (r=0.59 for men and r=0.67 for women, p

Objective: The objective of the study was to evaluate the effect of artificial high- and low-density materials on Bone mineral density (BMD)scans in dual-energy X-ray absorptiometry (DXA) method and emergence of black-hole artifact through GATE Monte Carlo simulation. Materials and Methods: GATE Monte Carlo code was utilized to simulate the artifact encountered in clinical scans acquired by HOLOGIC® bone densitometer. Two simplified phantoms were designed. The first one was a rectangular box with six smaller cubes inside and the second one was a body torso. Materials of cubes were spine bone, polymethyl methacrylate (PMMA), barium sulfate suspension in water, stainless steel, titanium alloy, and gold. The torso phantom contained objects of 5 vertebrae, bowel and 3 small spherical objects near the surface of the torso as piercing objects on the abdominal wall, each overlying the vertebrae. Using 100 and 140 kVp, spectral X-rays were generated to simulate DXA. For both phantoms, two simulations were carried out. The pair of projections acquired for each phantom were then subtracted and analyzed by curve fitting techniques. Results: Except for spine bone, in which radio-opacity decreases with increasing spectral X-ray energy (from 100 to 140 kVp), other squares exhibit little changes over different energies. PMMA shows consistently very low radio-opacity. Four other materials (barium sulfate in water, stainless steel alloy, titanium alloy, and gold), all attenuate the X-ray photons substantially. Except for spine bone, other materials are barely noticeable in pairwise subtracted images. In torso phantom, piercing objects are visualized as “holes” in vertebrae. Conclusion: Both artificial high- and low-density materials, compared to bone, are eliminated during the subtraction of dual-energy X-ray profiles and therefore, can create black-hole artifact.

Objective To investigate the ability of radiological parameter canal bone ratio (CBR) to assess bone mineral density and to differentiate between patients with primary and multiple osteoporotic vertebral compression fracture (OVCF). Methods A retrospective analysis was conducted on OVCF patients treated at our hospital. CBR was measured through full-spine x-rays. Patients were categorized into primary and multiple fracture groups. Receiver operating characteristic curve analysis and area under the curve (AUC) calculation were used to assess the ability of parameters to predict osteoporosis and multiple fractures. Predictors of T values were analyzed by multiple linear regression, and independent risk factors for multiple fractures were determined by multiple logistic regression analysis. Results CBR showed a moderate negative correlation with dual-energy x-ray absorptiometry T values (r = -0.642, p < 0.01). Higher CBR (odds ratio [OR], -6.483; 95% confidence interval [CI], -8.234 to -4.732; p < 0.01) and lower body mass index (OR, 0.054; 95% CI, 0.023–0.086; p < 0.01) were independent risk factors for osteoporosis. Patients with multiple fractures had lower T values (mean ±standard deviation [SD]: -3.76 ±0.73 vs. -2.83 ±0.75, p < 0.01) and higher CBR (mean ±SD: 0.54 ±0.07 vs. 0.46 ±0.06, p < 0.01). CBR had an AUC of 0.819 in predicting multiple fractures with a threshold of 0.53. T values prediction had an AUC of 0.816 with a threshold of -3.45. CBR > 0.53 was an independent risk factor for multiple fractures (OR, 14.66; 95% CI, 4.97–43.22; p < 0.01). Conclusion CBR is negatively correlated with bone mineral density (BMD) and can be a novel opportunistic BMD assessment method. It is a simple and effective measurement index for predicting multiple fractures, with predictive performance not inferior to T values.

Hip fractures contribute significantly to mortality in older adults. New methods to identify those at risk use dual-energy X-ray absorptiometry (DXA) images and advanced image processing. However, DXA images have an overlapping femur and pelvis and may contain boundary lines, making automation challenging. Herein, a 5-layer U-net convolutional neural network (CNN) was developed to segment the femur from hip DXA images. Images were used from the Canadian Longitudinal Study on Aging (CLSA, N=104) and Canadian Multicentre Osteoporosis Study (CaMos, N=105) databases for training, with manual contour drawing defining the 'true output' of each image. An algorithm was then developed to mask each hip image, and trained to predict subsequent masks. The CNN was tested with 44 additional CLSA images and 42 CaMos images. This proposed approach had an accuracy and intersection over union (IoU) of 97% and 0.57, and 93% and 0.51, for CaMos and CLSA scans, respectively. Furthermore, a series of augmentation techniques was applied to increase the data size, with accuracies of 96% and 94%, and IoU of 0.53 and 0.50. Overall, our strategy automatically determined the contour of the proximal femur using various clinical DXA images, a key step to automate fracture risk assessment in clinical practice. [ABSTRACT FROM AUTHOR]

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Purpose: Data on associations between adiposity and heart rate variability (HRV) in prepubertal children are limited. We examined the associations between adiposity indices and HRV, independent of lifestyle behaviors, comparing multiple indicators of adiposity, and explored differences between boys and girls. Methods: Data stem from 469 participants of the QUALITY cohort (630 children aged 8–10 years with a parental history of obesity). Adiposity indices included waist-to-height ratio, body mass index (BMI) percentiles and categories (overweight, obesity), dual-energy x-ray absorptiometry (DEXA) defined fat mass percentage and android/gynoid ratio. HRV indices in the frequency and the spectral domain were derived from a daytime 3-h Holter recording. Multivariable linear regression models were adjusted for age, sex, Tanner stage, physical activity, screen time, and fitness. Interactions between sex and adiposity were tested. Results: Greater adiposity was associated with decreased parasympathetic modulation and increased sympathetic dominance. Waist-to-height ratio was associated with lower parasympathetic activity: root mean square of the successive differences (RMSSD) [B = −23.32, 95% confidence interval (CI) −42.42, −4.22], pNN50 (B = −16.93, 95% CI − 28.58, − 5.27), LF/HF ratio (B = 1.83, 95% CI 0.97–2.70). Patterns of association were similar for android/gynoid ratio. Overweight was not associated with altered HRV. Obesity was negatively associated with RMSSD and pNN50 and positively with LF/HF ratio. Greater fat mass percentage was associated with lower RMSSD, pNN50, and HF, and increased LF/HF ratio. There were no differences between boys and girls. Conclusions: Specific markers of adiposity relate to altered HRV in childhood, with waist-to-height ratio being potentially a more relevant marker of HRV than BMI and more pragmatic than percent body fat. Trial registration: NCT03356262, 11 November 2017. [ABSTRACT FROM AUTHOR]

Purpose: Mineral bone disorder associated with chronic kidney disease (CKD-MBD) frequently persists after kidney transplantation (KTx), being due to pre-existing CKD-MBD, immunosuppressive therapies, and post-KTx hypophosphatemia. This study aimed to evaluate bone biomarkers and microarchitecture using high resolution peripheral quantitative computed tomography (HR-pQCT) at the time of KTx and 6 months thereafter and to compare these results with those of matched healthy controls (HC). Methods: This study presented the single-center subgroup of patients aged between 10 and 18 years included in the prospective "Bone Microarchitecture in the Transplant Patient" study (TRANSOS-NCT02729142). Patients undergoing a first KTx were matched (1:2) with HC from the "Vitamin D, Bones, Nutritional and Cardiovascular Status" cohort (VITADOS) on sex, pubertal stage, and age. Results: At a median (interquartile range, IQR) age of 15 [13; 16] years, 19 patients (6 girls, 7 pre-emptive KTx, 7 steroid-sparing immunosuppressive strategies) underwent a first KTx, with a median [IQR] parathyroid hormone level of 1.9 [1.4; 2.9] the upper limit of normal (ULN). Higher total and trabecular bone densities, along with superior trabecular microarchitecture, were observed at KTx compared to HC. Six months post-KTx, patients had significantly impaired trabecular parameters at the radius, while results were not significantly different at the weight-bearing tibia, neither cortical parameters at both sites. Six months post-KTx, 6 (32%) patients still present with metabolic acidosis, 10 (53%) persistent hyperparathyroidism (always < 2 ULN), and 5 (26%) elevated FGF23 levels; 11 (58%) received phosphate supplementation. Conclusions: Bone density and microarchitecture at the time of KTx were superior compared to HC, but radial trabecular bone microarchitecture impairment observed 6 months post-KTx may reflect subtle albeit present post-KTx CKD-MBD. What is Known? • Mineral bone disorder associated with chronic kidney disease (CKD-MBD) frequently persists after kidney transplantation (KTx) and is associated with morbidity. However, biochemical parameters and dual X-ray absorptiometry (DXA) are poor predictors of the underlying bone disease. What is new? • The present study on 19 adolescent KTx recipients with adequate CKD-MBD control at the time of KTx reveals no significant bone disease compared to matched healthy controls. Microarchitecture impairment observes 6 months post-KTx may reflect subtle, albeit present, post-KTx CKD-MBD. [ABSTRACT FROM AUTHOR]

Abstract Background Osteoporosis is increasingly being recognized in children, mostly secondary to systemic underlying conditions or medication. However, no imaging modality currently provides a full evaluation of bone health in children. We compared DXA, a radiographic bone health index (BHI (BoneXpert) and cone-beam CT for the assessment of low bone mass in children with juvenile idiopathic arthritis (JIA). Methods Data used in the present study was drawn from a large multicentre study including 228 children aged 4–16 years, examined between 2015 and 2020. All had a radiograph of the left hand, a DXA scan and a cone-beam CT of the temporomandibular joints within four weeks of each other. For the present study, we included 120 subjects, selected based on DXA BMD and BoneXpert BHI to secure values across the whole range to be tested. Results One hundred and twenty children (60.0% females) were included, mean age 11.6 years (SD 3.1 years). There was a strong correlation between the absolute values of BHI and BMD for both total body less head (TBLH) (r = 0.75, p

Abstract Objective To conduct a bibliometric analysis of the prospects and obstacles associated with dual- and multi-energy CT in thoracic disease, emphasizing its current standing, advantages, and areas requiring attention. Methods The Web of Science Core Collection was queried for relevant publications in dual- and multi-energy CT and thoracic applications without a limit on publication date or language. The Bibliometrix packages, VOSviewer, and CiteSpace were used for data analysis. Bibliometric techniques utilized were co-authorship analyses, trend topics, thematic map analyses, thematic evolution analyses, source’s production over time, corresponding author’s countries, and a treemap of authors’ keywords. Results A total of 1992 publications and 7200 authors from 313 different sources were examined in this study. The first available document was published in November 1982, and the most cited article was cited 1200 times. Siemens AG in Germany emerged as the most prominent author affiliation, with a total of 221 published articles. The most represented scientific journals were the “European Radiology” (181 articles, h-index = 46), followed by the “European Journal of Radiology” (148 articles, h-index = 34). Most of the papers were from Germany, the USA, or China. Both the keyword and topic analyses showed the history of dual- and multi-energy CT and the evolution of its application hotspots in the chest. Conclusion Our study illustrates the latest advances in dual- and multi-energy CT and its increasingly prominent applications in the chest, especially in lung parenchymal diseases and coronary artery diseases. Photon-counting CT and artificial intelligence will be the emerging hot technologies that continue to develop in the future. Critical relevance statement This study aims to provide valuable insights into energy-based imaging in chest disease, validating the clinical application of multi-energy CT together with photon-counting CT and effectively increasing utilization in clinical practice. Key Points Bibliometric analysis is fundamental to understanding the current and future state of dual- and multi-energy CT. Research trends and leading topics included coronary artery disease, pulmonary embolism, and radiation dose. All analyses indicate a growing interest in the use of energy-based imaging techniques for thoracic applications. Graphical Abstract

Song Wang,1,&ast; Xiang Zhang,1,&ast; Bo Qu,2,&ast; Kunhai Yang,1 Yongrong Hu,1 Hao Liu,2 Juntao Hong,2 Hao Niu,3 Hongsheng Yang2 1School of Clinical Medicine, Chengdu Medical College, Chengdu, Sichuan, People’s Republic of China; 2Department of Orthopaedics, First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, People’s Republic of China; 3Computer Science of Sichuan University, Chengdu, Sichuan, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Hao Niu, Computer Science of Sichuan University, Chengdu, Sichuan, People’s Republic of China, Email 13438368112@139.com Hongsheng Yang, Department of Orthopaedics, First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, People’s Republic of China, Email hongsheng228@163.comPurpose: This study aims to develop a novel MRI-based paravertebral muscle quality (PVMQ) score for assessing muscle quality and to investigate its correlation with the degree of fat infiltration (DFF) and the vertebral bone quality (VBQ) score of paravertebral muscles. Additionally, the study compares the effectiveness of the PVMQ score and the VBQ score in assessing muscle quality and bone quality.Methods: PVMQ scores were derived from the ratio of paravertebral muscle signal intensity (SI) to L3 cerebrospinal fluid SI on T2-weighted MRI. Image J software assessed paravertebral muscle cross-sectional area (CSA) and DFF. Spearman rank correlation analyses explored associations between PVMQ, VBQ scores, DFF, and T-scores in both genders. Receiver operating characteristic (ROC) curves compared PVMQ and VBQ scores’ effectiveness in distinguishing osteopenia/osteoporosis and high paraspinal muscle DFF.Results: In this study of 144 patients (94 females), PVMQ scores were significantly higher in osteoporosis and osteopenia groups compared to normals, with variations observed between genders (P < 0.05). PVMQ showed stronger positive correlation with VBQ scores and DFF in females than males (0.584 vs 0.445, 0.579 vs 0.528; P < 0.01). ROC analysis favored PVMQ over VBQ for low muscle mass in both genders (AUC = 0.767 vs 0.718, 0.793 vs 0.718). VBQ was better for bone mass in males (0.737/0.865 vs 0.691/0.858), whereas PVMQ excelled for females (0.808/0.764 vs 0.721/0.718).Conclusion: The novel PVMQ score provides a reliable assessment of paravertebral muscle quality and shows a strong correlation with VBQ scores and DFF, particularly in females. It outperforms VBQ scores in evaluating muscle mass and offers valuable insights for assessing bone mass in females. These findings underscore the potential of the PVMQ score as a dual-purpose tool for evaluating both muscle and bone health, informing future research and clinical practice.Keywords: muscle quality, osteoporosis, magnetic resonance imaging, dual-energy X-ray absorptiometry, vertebral bone quality score, osteosarcopenia

Objectives: This study investigates the regional variation in areal bone mineral density (aBMD) at the distal radius, a critical site for osteoporosis-related fractures. Understanding aBMD distribution is essential for accurate diagnosis and management of osteoporosis. Methods: The study involved 261 participants aged over 50. Using dual-energy X-ray absorptiometry (DXA) scans, aBMD was recorded across contiguous regions of the distal radius. Factors considered include age, sex, and hand dominance, providing a comprehensive view of aBMD distribution. Results: The findings indicated a consistent pattern in aBMD distribution along the radius, with a plateau around the one-third distance from the wrist. Notably, significant differences in aBMD were observed between age groups, especially among post-menopausal women. The study also recorded minor variations in aBMD between dominant and non-dominant forearms. Conclusions: The study's insights into aBMD variation at the distal radius have implications for osteoporosis research and clinical diagnosis. It highlights the importance of standardized region of interest placement in DXA scans for accurate assessment.

Background Osteoporosis is the most common metabolic bone disease and can cause fragility fractures. Despite this, screening utilization rates for osteoporosis remain low among populations at risk. Automated bone mineral density (BMD) estimation using computed tomography (CT) can help bridge this gap and serve as an alternative screening method to dual-energy X-ray absorptiometry (DXA). Methods The feasibility of an opportunistic and population agnostic screening method for osteoporosis using abdominal CT scans without bone densitometry phantom-based calibration was investigated in this retrospective study. A total of 268 abdominal CT-DXA pairs and 99 abdominal CT studies without DXA scores were obtained from an oncology specialty clinic in the Republic of Korea. The center axial CT slices from the L1, L2, L3, and L4 lumbar vertebrae were annotated with the CT slice level and spine segmentation labels for each subject. Deep learning models were trained to localize the center axial slice from the CT scan of the torso, segment the vertebral bone, and estimate BMD for the top four lumbar vertebrae. Results Automated vertebra-level DXA measurements showed a mean absolute error (MAE) of 0.079, Pearson’s r of 0.852 (P

Circulating blood is an important plasma free amino acids (PFAAs) reservoir and a pivotal link between metabolic pathways. No comparisons are available between athletes with opposite training adaptations that include a broader spectrum of both proteinogenic and non-proteinogenic amino acids, and that take into account skeletal muscle mass. We hypothesized that the levels of the exercise-induced PFAAs concentration are related to the type of training-related metabolic adaptation. We compared highly trained endurance athletes (n = 11) and sprinters (n = 10) aged 20‒35 years who performed incremental exercise until exhaustion. Venous blood was collected before and during the test and 30-min recovery (12 samples). Forty-two PFAAs were assayed using LC-ESI-MS/MS technique. Skeletal muscle mass was estimated using dual X-ray absorptiometry method. Glutamine and alanine were dominant PFAAs throughout the whole exercise and recovery period (~350‒650 μmol∙L-1). Total, combined proteinogenic, non-essential, and non-proteinogenic PFAAs levels were significantly higher in endurance athletes than sprinters (ANOVA group effects: p = 0.007, η2 = 0.321; p = 0.011, η2 = 0.294; p = 0.003, η2 = 0.376; p = 0.001, η2 = 0.471, respectively). The exercise response was more pronounced in endurance athletes, especially for non-proteinogenic PFAAs (ANOVA interaction effect: p = 0.038, η2 = 0.123). Significant between-group differences were observed for 19 of 33 PFAAs detected, including 4 essential, 7 non-essential, and 8 non-proteinogenic ones. We demonstrated that the PFAAs response to incremental aerobic exercise is associated with the type of training-related metabolic adaptation. A greater turnover and availability of circulating PFAAs for skeletal muscles and other body tissues is observed in endurance- than in sprint-trained individuals. Non-proteinogenic PFAAs, despite low concentrations, also respond to exercise loads, indicating their important, though less understood role in exercise metabolism. Our study provides additional insight into the exercise-induced physiological response of PFAAs, and may also provide a rationale in discussions regarding dietary amino acid requirements in high-performance athletes with respect to sports specialization. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis is a major global health issue, weakening bones and increasing fracture risk. Dual-energy X-ray absorptiometry (DXA) is the standard for measuring bone mineral density (BMD) and diagnosing osteoporosis, but its costliness and complexity impede widespread screening adoption. Predictive modeling using genetic and clinical data offers a cost-effective alternative for assessing osteoporosis and fracture risk. This study aims to develop BMD prediction models using data from the UK Biobank (UKBB) and test their performance across different ethnic and geographical populations. Methods and findings: We developed BMD prediction models for the femoral neck (FNK) and lumbar spine (SPN) using both genetic variants and clinical factors (such as sex, age, height, and weight), within 17,964 British white individuals from UKBB. Models based on regression with least absolute shrinkage and selection operator (LASSO), selected based on the coefficient of determination (R2) from a model selection subset of 5,973 individuals from British white population. These models were tested on 5 UKBB test sets and 12 independent cohorts of diverse ancestries, totaling over 15,000 individuals. Furthermore, we assessed the correlation of predicted BMDs with fragility fractures risk in 10 years in a case-control set of 287,183 European white participants without DXA-BMDs in the UKBB. With single-nucleotide polymorphism (SNP) inclusion thresholds at 5×10−6 and 5×10−7, the prediction models for FNK-BMD and SPN-BMD achieved the highest R2 of 27.70% with a 95% confidence interval (CI) of [27.56%, 27.84%] and 48.28% (95% CI [48.23%, 48.34%]), respectively. Adding genetic factors improved predictions slightly, explaining an additional 2.3% variation for FNK-BMD and 3% for SPN-BMD over clinical factors alone. Survival analysis revealed that the predicted FNK-BMD and SPN-BMD were significantly associated with fragility fracture risk in the European white population (P < 0.001). The hazard ratios (HRs) of the predicted FNK-BMD and SPN-BMD were 0.83 (95% CI [0.79, 0.88], corresponding to a 1.44% difference in 10-year absolute risk) and 0.72 (95% CI [0.68, 0.76], corresponding to a 1.64% difference in 10-year absolute risk), respectively, indicating that for every increase of one standard deviation in BMD, the fracture risk will decrease by 17% and 28%, respectively. However, the model's performance declined in other ethnic groups and independent cohorts. The limitations of this study include differences in clinical factors distribution and the use of only SNPs as genetic factors. Conclusions: In this study, we observed that combining genetic and clinical factors improves BMD prediction compared to clinical factors alone. Adjusting inclusion thresholds for genetic variants (e.g., 5×10−6 or 5×10−7) rather than solely considering genome-wide association study (GWAS)-significant variants can enhance the model's explanatory power. The study highlights the need for training models on diverse populations to improve predictive performance across various ethnic and geographical groups. Yong Liu and co-workers compare Author summary: Why was this study done?: Osteoporosis diagnosis via bone mineral density (BMD) measurements by dual-energy X-ray absorptiometry (DXA) is impractical for large-scale screening, especially in resource-limited areas. Genomic data offers a cost-effective alternative for predicting disease risk, but current methods often overlook sub-significant variants and clinical factors. Most existing genomic prediction methods are based on European ancestry, with limited evaluation in other ethnic populations. What did the researchers do and find?: We developed BMD prediction models for femoral neck (FNK) and lumbar spine (SPN) using a training set of 17,964 individuals from British white ancestry in UK Biobank (UKBB), integrating clinical and genetic factors. We observed that strong correlations between predicted and true BMDs (R2≈25% for FNK-BMD and R2≈45% for SPN-BMD) and significant associations with fracture risk in European ancestry populations. And we identified the optimal P-value thresholds for FNK-BMD (5×10−6) and SPN-BMD (5×10−7), noting that these thresholds vary by trait and sample size. By applying the prediction models on 5 UKBB test sets and 12 independent cohorts of diverse ancestries, totaling over 15,000 individuals, we observed that the BMD prediction models performed well in UKBB European populations but less effectively in other ancestry groups and independent cohorts. What do these findings mean?: We show that genetic factors could improve the performance of DXA-BMD prediction. Within the same population, the predicted BMDs can help prioritize individuals at high risk of fragility fracture for tailored treatments. Genetic prediction methods need rigorous evaluation before application to different populations, emphasizing the importance of diverse population training. Study limitations include differences in the distribution of clinical factors such as sex and age between the UKBB data sets and the independent cohorts, as well as the inclusion of only single-nucleotide polymorphisms (SNPs) as genetic factors. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis is increasingly being recognized in children, mostly secondary to systemic underlying conditions or medication. However, no imaging modality currently provides a full evaluation of bone health in children. We compared DXA, a radiographic bone health index (BHI (BoneXpert) and cone-beam CT for the assessment of low bone mass in children with juvenile idiopathic arthritis (JIA). Methods: Data used in the present study was drawn from a large multicentre study including 228 children aged 4–16 years, examined between 2015 and 2020. All had a radiograph of the left hand, a DXA scan and a cone-beam CT of the temporomandibular joints within four weeks of each other. For the present study, we included 120 subjects, selected based on DXA BMD and BoneXpert BHI to secure values across the whole range to be tested. Results: One hundred and twenty children (60.0% females) were included, mean age 11.6 years (SD 3.1 years). There was a strong correlation between the absolute values of BHI and BMD for both total body less head (TBLH) (r = 0.75, p < 0.001) and lumbar spine (L1-L4) (r = 0.77, p < 0.001). The correlation between BHI standard deviation score (SDS) and BMD TBLH Z-scores was weak (r = 0.34) but significant (0 = 0.001), varying from weak (r = 0.31) to moderate (r = 0.42) between the three study sites. Categorizing BHI SDS and DXA BMD Z-scores on a 0–5 scale yielded a weak agreement between the two for both TBLH and LS, with w-kappa of 0.2, increasing to 0.3 when using quadratic weights. The agreement was notably higher for one of the three study sites as compared to the two others, particularly for spine assessment, yielding a moderate kappa value of 0.4 – 0.5. For cone-beam CT, based on a 1–3 scale, 59 out of 94 left TMJ's were scored as 1 and 31 as score 2 by the first observer vs. 87 and 7 by the second observer yielding a poor agreement (kappa 0.1). Conclusions: Categorizing DXA LS and automated radiographic Z-scores on a 0–5 scale gave a weak to moderate agreement between the two methods, indicating that a hand radiograph might provide an adjuvant tool to DXA when assessing bone health children with JIA, given thorough calibration is performed. [ABSTRACT FROM AUTHOR]

Background: The lean soft tissue mass (LSTM) of the limbs is approximately 63% of total skeletal muscle mass. For athletes, measurement of limb LSTM is the basis for rapid estimation of skeletal muscle mass. This study aimed to establish the estimation equation of LSTM in Asian athletes using bioelectrical impedance analysis (BIA). Methods: A total of 198 athletes (121 males, 77 females; mean age 22.04 ± 5.57 years) from different sports in Taiwan were enrolled. A modeling group (MG) of 2/3 (n = 132) of subjects and a validation group (VG) of 1/3 (n = 68) were randomly assigned. Using the InBody S-10, resistance and reactance were measured at 50 kHz from the right palm to the right sole while the participant was in the supine position. Predictor variables were height (h), weight (W), age, Sex, Xc, resistance index (RI; RI = h2 / R). LSTM of arms and legs measured by dual-energy X-ray absorptiometry (DXA) was the response variable. Multivariate stepwise regression analysis method was used to establish BIA estimation equations as ArmsLSTMBIA-Asian and LegsLSTMBIA-Asian. Estimation equations performance was confirmed by cross-validation. Results: Estimation equation "ArmsLSTMBIA-Asian = 0.096 h2/R– 1.132 Sex + 0.030 Weight + 0.022 Xc– 0.022 h + 0.905, r2 = 0.855, SEE = 0.757 kg, n = 132" and "LegsLSTMBIA Asian = 0.197h2/R" + 0.120 h– 1.242 Sex + 0.055 Weight– 0.052 Age + 0.033 Xc –16.136, r2 = 0.916, SEE = 1.431 kg, n = 132" were obtained from MG. Using DXA measurement results of VG for correlation analysis and Limit of Agreement (LOA) of Bland-Altman Plot, ArmsLST is 0.924, -1.53 to 1.43 kg, and LegsLST is 0.957, -2.68 to 2.90 kg. Conclusion: The established single-frequency BIA hand-to-foot (whole body) estimation equation quickly and accurately estimates LSTM of the arms and legs of Asian athletes. [ABSTRACT FROM AUTHOR]

Musculoskeletal changes occur with gender-affirming hormonal therapy (GAHT) and gender-affirming surgery (GAS) used in the care of transgender adolescents and adults. Survey results have shown that orthopaedic surgeons desire to care for transgender individuals but express concern over a knowledge deficit. This article reviews the physiology and pathophysiology that may occur with GAHT and GAS. Transgender women have lower bone mineral density (BMD) prior to GAHT than cisgender men. Limited fracture data would suggest that transgender women >50 years of age have fracture rates similar to those of cisgender women. Transgender men have normal BMD prior to GAHT and are not at an increased risk for fracture compared with cisgender women. The use of puberty-blocking medications in the care of transgender youth does result in a decline in BMD, which returns to baseline with GAHT, but the effect of delaying puberty on maximal BMD and the lifetime fracture risk are unknown. At present, dual x-ray absorptiometry (DXA) is used to measure BMD and assess fracture risk. Attention should be paid to using the appropriate reference group in the interpretation of DXA for transgender individuals. Promote musculoskeletal health by ensuring appropriate calcium, vitamin D, weight-bearing activity, and a healthy lifestyle. Adherence to GAHT needs to be encouraged to avoid bone loss. Data with regard to therapy for osteoporosis in transgender patients have been lacking, but, at present, use of available therapies is expected to be effective. Information with regard to differences in other musculoskeletal health issues such as joint injuries has been lacking in transgender individuals. [ABSTRACT FROM AUTHOR]

Objective: To analyse the changes of bone metabolic markers in type 2 diabetes patients with osteoporosis, and analyze the risk factors. Methods: Eighty patients with type 2 diabetes and osteoporosis admitted to our hospital from January 2022 to December 2022 were selected as the research objects, and they were divided into osteoporosis group. Eighty patients with type 2 diabetes and non osteoporosis admitted to our hospital in the same period were selected as the non osteoporosis group, and 80 healthy volunteers who came to our hospital for physical examination in the same period were selected as the control group. The expression level of bone metabolic markers in three groups of subjects was compared, and dual energy X-ray absorptiometry was used as the "gold standard" for the diagnosis of osteoporosis. The ROC curve of subjects was established, and the critical value of related bone metabolic markers for the diagnosis of type 2 diabetes with osteoporosis was analyzed. Finally, the disease risk factors were analyzed. Results: There was no significant difference in the levels of alkaline phosphatase (ALP), blood phosphorus (P), and calcium (Ca) among the three groups of subjects (P＞0.05). However, there were differences in the levels of urinary type 1 collagen C-terminal peptide (CTX-1), osteocalcin, and parathyroid hormone (PTH) among the three groups of subjects. There were also differences in the levels of CTX-1, osteocalcin, and parathyroid hormone (PTH) among the three groups of subjects PTH was higher than that of the non osteoporosis group and control group, while osteocalcin was lower than that of the non osteoporosis group and control group (P＜0.05); The critical value of CTX-1 for the diagnosis of type 2 diabetes with osteoporosis was 525.74 μg/mmoL Cr, the sensitivity was 83.35%, the specificity was 67.95%, the critical value of osteocalcin was 14.12ng/L, the sensitivity was 81.27%, the specificity was 79.46%, and the critical value of PTH was 45.75 pmol/L, the sensitivity was 74.84%, the specificity was 81.36%; There was no difference between the osteoporosis group and the non osteoporosis group in terms of gender, duration of diabetes, combined with other basic diseases, peripheral neuropathy, and fasting blood glucose (P＞0.05). There were differences between the osteoporosis group and the non osteoporosis group in terms of age, BMI, peripheral vascular disease, diabetes nephropathy, retinopathy, glycosylated hemoglobin, CTX-1, osteocalcin, and PTH levels (P＜0.05); Age, diabetes nephropathy, retinopathy, glycosylated hemoglobin, CTX-1, osteocalcin, PTH were independent risk factors for type 2 diabetes with osteoporosis (P＜0.05). Conclusion: The levels of CTX-1 and PTH in type 2 diabetes patients with osteoporosis increase and osteocalcin decreases. The three can provide important reference for the clinical diagnosis of type 2 diabetes patients with osteoporosis. Age, diabetes nephropathy, retinopathy, glycosylated hemoglobin, CTX-1, osteocalcin and PTH are independent risk factors for type 2 diabetes patients with osteoporosis. [ABSTRACT FROM AUTHOR]

Objective: To conduct a bibliometric analysis of the prospects and obstacles associated with dual- and multi-energy CT in thoracic disease, emphasizing its current standing, advantages, and areas requiring attention. Methods: The Web of Science Core Collection was queried for relevant publications in dual- and multi-energy CT and thoracic applications without a limit on publication date or language. The Bibliometrix packages, VOSviewer, and CiteSpace were used for data analysis. Bibliometric techniques utilized were co-authorship analyses, trend topics, thematic map analyses, thematic evolution analyses, source's production over time, corresponding author's countries, and a treemap of authors' keywords. Results: A total of 1992 publications and 7200 authors from 313 different sources were examined in this study. The first available document was published in November 1982, and the most cited article was cited 1200 times. Siemens AG in Germany emerged as the most prominent author affiliation, with a total of 221 published articles. The most represented scientific journals were the "European Radiology" (181 articles, h-index = 46), followed by the "European Journal of Radiology" (148 articles, h-index = 34). Most of the papers were from Germany, the USA, or China. Both the keyword and topic analyses showed the history of dual- and multi-energy CT and the evolution of its application hotspots in the chest. Conclusion: Our study illustrates the latest advances in dual- and multi-energy CT and its increasingly prominent applications in the chest, especially in lung parenchymal diseases and coronary artery diseases. Photon-counting CT and artificial intelligence will be the emerging hot technologies that continue to develop in the future. Critical relevance statement: This study aims to provide valuable insights into energy-based imaging in chest disease, validating the clinical application of multi-energy CT together with photon-counting CT and effectively increasing utilization in clinical practice. Key Points: Bibliometric analysis is fundamental to understanding the current and future state of dual- and multi-energy CT. Research trends and leading topics included coronary artery disease, pulmonary embolism, and radiation dose. All analyses indicate a growing interest in the use of energy-based imaging techniques for thoracic applications. [ABSTRACT FROM AUTHOR]

Background: As implant treatment cases increase, many cases of failure/side effects also occur. Generally, dental clinics determine the density of the jawbone using cone beam CT (CBCT). Considering the known potential role of this tool for bone assessment in primary osteoporosis, this study evaluated patients with secondary endocrine causes of low bone mass. Methods: The study included 83 patients with endocrine causes of osteoporosis who were evaluated by dual-energy X-ray absorptiometry (DXA), trabecular bone score (TBS), and mental foramen (MF) region CBCT. The following CBCT indices were measured: anterior (A)—thickness of inferior mandibular cortex 10 mm anterior from MF; molar (M)—thickness of inferior mandibular cortex 10 mm posterior from MF; posterior (P)—thickness of inferior mandibular cortex 25 mm posterior from MF; symphysis (S)—thickness of inferior mandibular cortex equidistant from the centers of right and left MF. Results: The highest correlation coefficient in the secondary causes group was between the A index and the lumbar BMD (r = 0.375, p = 0.001) and the P index and the femoral neck BMD (r = 0.38, p = 0.001). Hypercortisolism seems to be the most predictable cause of secondary osteoporosis using the A, M, and P indices. The A, M, and P indices showed predictive values of the bone micro-architecture that was evaluated using TBS score, and were statistically significant. The symphysis index does not significantly predict osteoporosis or impaired bone micro-architecture. Conclusions: These findings support the potential usefulness of A, M, and P CBCT-derived radiomorphometric mandibular indices in secondary osteoporosis, underlining the well-known effects of these pathologies on bone micro-architecture rather than bone quantity. [ABSTRACT FROM AUTHOR]

Aims: Dynapenia is a noteworthy health issue contributing to increased risk of falling, but its co-occurrence with osteoporosis in elderly individuals with type 2 diabetes mellitus (T2DM) has not been well explored. Therefore, this study aimed to establish the association between osteoporosis and dynapenia, focusing on T2DM females due to their high prevalence of osteoporosis and fragility. Methods: We conducted a cross-sectional study to recruit a total of 103 T2DM patients (43 males and 60 females), aged between 50 and 80 years with median 68.0 years. Dual-energy X-ray absorptiometry (DXA) and dominant hand grip strength measurements were performed to define body composition, osteoporosis, and dynapenia in a sex-specific manner. Results: Higher prevalence of dynapenia and dyna-osteoporosis was observed in female T2DM patients with a significantly positive correlation between osteoporosis and dynapenia even after adjustment of body mass index (BMI). By performing a multivariate logistic regression analysis, both BMI and osteoporosis were identified as risk predictors for the development of dynapenia in female T2DM patients with odds ratios (95% CIs) of 1.234 (1.029–1.480) and 4.883 (1.352–17.630), respectively. Conclusions: Our results point out there is high, female-specific co-occurrence of osteoporosis and dynapenia in T2DM patients. Moreover, having osteoporosis and increased BMI might boost the risk of dynapenia in elderly females with T2DM. [ABSTRACT FROM AUTHOR]

Background: Sedentary behavior is linked to excess fat mass; however, this association may be inconclusive due to potential measurement errors in self-reported sedentary behavior. Objective: To assess the association between changes in sedentary behavior and fat mass in a Cohort of Health Workers (HWCS) from 2004 to 2010. Methods: A total of 1,285 adults participating in the Cohort of Health Workers were evaluated in 2004 and 2010. Fat mass (kg) was measured by dual X-ray absorptiometry. A self-administered questionnaire was used to estimate the sedentary behavior. Sedentary behavior was also estimated using accelerometry in a sample of 142 health workers. Accelerometry data were used to correct self-reported sedentary behavior using a generalized linear model, which included values for sleeping time, age, sex, sedentary behavior, glucose, and triglycerides. Concordance between both methods was assessed using a kappa and Bland–Altman analysis. Once sedentary behavior was corrected, the values were used to evaluate the association between changes in sedentary behavior and body fat mass using a fixed effect model in the cohort, adjusting for confounders. Results: Self-reported sedentary behavior was 2.8 ± 1.8 and 2.3 ± 1.6 h/day, and body fat mass was 24.9 ± 8.1 and 26.8 ± 8.5 kg in 2004 and 2010, respectively. After applying the correction model, the self-reported sedentary behavior was 7.6 ± 1.2 and 7.5 ± 1.2 h/day in 2004 and 2010, respectively. For every hour increase in corrected sedentary behavior, there was an observed increase of 0.847 (p > 0.001) kg in body fat mass during the 6.8 years in the Cohort of Health Workers from 2004 to 2010. Conversely, non-corrected self-reported sedentary behavior was associated with a non-significant reduction of 0.097 kg (p = 0.228) for every hour of sedentary behavior. Conclusions: Increased sedentary behavior was associated with increased body fat mass when corrected self-reported sedentary behavior was used. Implementing public health strategies to reduce sedentary behavior is imperative. [ABSTRACT FROM AUTHOR]

Background and aim: Cardiovascular disease (CVD) risk among individuals across different categories of metabolic obesity phenotypes is controversial. The study used body fat percentage (BFP) or body mass index (BMI) to categorize obese status and to investigate the association between metabolic obesity phenotypes and CVD risk in a nationally representative population. Methods: This cross-sectional study included 49463 adult participants in National Health and Nutrition Examination Survey from 1999 to 2020. Metabolic healthy status was defined by the absence of metabolic syndrome according to the revised National Cholesterol Education Program Adult Treatment Group definition. Obesity was identified by BFP, assessed by dual-energy X-ray absorptiometry scan, and BMI. The primary outcome was CVD prevalence. The multivariable logistic regression model and restricted cubic spline analyses were used to examine the associations between metabolic obesity phenotypes and the risk of CVD. Results: Among 49463 adult participants, 32.12% were metabolically unhealthy, 34.10% were overweight, 37.94% were obese; and 8.41% had CVD. Compared with metabolic healthy normal weight, metabolic healthy obesity, and metabolic unhealthy normal weight/overweight/obesity were all associated with increased CVD risk with adjusted odds ratios (95% confidence intervals) of 1.45 (1.14–1.85), 2.80(1.53–5.11), 2.55(1.88–3.47), and 2.96(2.18–4.02), respectively. Nonlinear dose-response relationships between BFP and CVD were observed both in metabolically healthy and unhealthy participants (both P for non-linearity<0.0001). When obesity was defined with BMI, there were a similar prevalence of obesity, and similar associations between metabolic obesity phenotypes and CKD risks. Conclusions: Metabolic healthy and unhealthy obesity were both associated with higher risks of CVD, whether using BFP or BMI to define obese status. It suggests that metabolic obesity phenotype is a risk factor for CVD. [ABSTRACT FROM AUTHOR]

Osteoporosis is a chronic disease that affects millions of patients worldwide and is characterized by low bone mineral density (BMD) and increased risk of fractures. Notably, natural molecules can increase BMD and exert pro-osteogenic effects. Noteworthily, the nutraceutical BlastiMin Complex® (Mivell, Italy, European Patent Application EP4205733A1) can induce differentiation of human bone marrow mesenchymal stem cells (BM-MSCs) in osteoblasts and can exert in vitro pro-osteogenic and anti-inflammatory effects. Thus, the purpose of this study was to verify the effects of BlastiMin Complex® on bone turnover markers (BTMs) and BMD in patients with senile and postmenopausal osteopenia or osteoporosis. The efficacy of BlastiMin Complex® on BTMs in serum was evaluated through biochemical assays. BMD values were analyzed by dual-energy X-ray absorptiometry (DXA) and Radiofrequency Echographic Multi Spectrometry (R.E.M.S.) techniques, and the SNPs with a role in osteoporosis development were evaluated by PCR. Clinical data obtained after 12 months of treatment showed an increase in bone turnover index, a decrease in C-reactive protein levels, and a remarkable increase in P1NP levels, indicating the induction of osteoblast proliferation and activity in the cohort of 100% female patients recruited for the study. These findings show that the nutraceutical BlastiMin Complex® could be used as an adjuvant in combination with synthetic drugs for the treatment of osteoporosis pathology. [ABSTRACT FROM AUTHOR]

Opportunistic osteoporosis screening using deep learning (DL) analysis of low-dose chest CT (LDCT) scans is a potentially promising approach for the early diagnosis of this condition. We explored bone mineral density (BMD) profiles across all adult ages and prevalence of osteoporosis using LDCT with DL in a Korean population. This retrospective study included 1915 participants from two hospitals who underwent LDCT during general health checkups between 2018 and 2021. Trabecular volumetric BMD of L1-2 was automatically calculated using DL and categorized according to the American College of Radiology quantitative computed tomography diagnostic criteria. BMD decreased with age in both men and women. Women had a higher peak BMD in their twenties, but lower BMD than men after 50. Among adults aged 50 and older, the prevalence of osteoporosis and osteopenia was 26.3% and 42.0%, respectively. Osteoporosis prevalence was 18.0% in men and 34.9% in women, increasing with age. Compared to previous data obtained using dual-energy X-ray absorptiometry, the prevalence of osteoporosis, particularly in men, was more than double. The automated opportunistic BMD measurements using LDCT can effectively predict osteoporosis for opportunistic screening and identify high-risk patients. Patients undergoing lung cancer screening may especially profit from this procedure requiring no additional imaging or radiation exposure. [ABSTRACT FROM AUTHOR]

Background: There is limited research providing an overall understanding of bone mineral density (BMD) changes throughout different stages of life. This study aimed to investigate the pattern of BMD changes across childhood, adolescence, adulthood, and old age, as well as exploring the critical time of peak BMD (PBMD). Methods: Participants of three major ethnicities from National Health and Nutrition Examination Survey 1999 to 2018 were involved: 46,381 and 20,944 participants aged 8–85 years old were included in the Lumbar spine BMD (LSBMD) and femoral neck BMD (FNBMD) studies, respectively. BMD was measured using dual-energy X-ray absorptiometry. The generalized additive model was used to construct smoothed percentile curves. Results: Both males and females experienced a sharp increase in LSBMD during puberty, with females reaching their PBMD earlier than males. Females' LSBMD remained higher than males' before the age of approximately 50, except for Non-Hispanic Blacks. For males, LSBMD reached a plateau at around 30 years old after reaching the peak value. Females exhibited two peak points on the fitted curves, with the second PBMD occurring around 36–37 years old. Ethnic variations were observed, with Non-Hispanic Blacks displaying the highest BMD levels at all ages. Non-Hispanic Whites and Mexican Americans had lower BMD levels, with Mexican Americans generally exhibiting the lowest BMD. FNBMD reached its peak earlier than LSBMD, and males consistently had higher FNBMD than females. Conclusions: This nationally representative study contributes to the understanding of BMD changes across the lifespan, and might provide guidance for bone health interventions in different population groups. [ABSTRACT FROM AUTHOR]

Whether trace metals modify breast density, the strongest predictor for breast cancer, during critical developmental stages such as puberty remains understudied. Our study prospectively evaluated the association between trace metals at Tanner breast stage B1 (n = 291) and at stages both B1 and B4 (n = 253) and breast density at 2 years post‐menarche among Chilean girls from the Growth and Obesity Cohort Study. Dual‐energy x‐ray absorptiometry assessed the volume of dense breast tissue (absolute fibroglandular volume [FGV]) and percent breast density (%FGV). Urine trace metals included arsenic, barium, cadmium, cobalt, cesium, copper, magnesium, manganese, molybdenum, nickel, lead, antimony, selenium, tin, thallium, vanadium, and zinc. At B1, a doubling of thallium concentration resulted in 13.69 cm3 increase in absolute FGV (β: 13.69, 95% confidence interval [CI]: 2.81, 24.52), while a doubling of lead concentration resulted in a 7.76 cm3 decrease in absolute FGV (β: –7.76, 95%CI: −14.71, −0.73). At B4, a doubling of barium concentration was associated with a 10.06 cm3 increase (β: 10.06, 95% CI: 1.44, 18.60), copper concentration with a 12.29 cm3 increase (β: 12.29, 95% CI: 2.78, 21.56), lead concentration with a 9.86 cm3 increase (β: 9.86, 95% CI: 0.73, 18.98), antimony concentration with a 12.97 cm3 increase (β: 12.97, 95% CI: 1.98, 23.79) and vanadium concentration with a 13.14 cm3 increase in absolute FGV (β: 13.14, 95% CI: 2.73, 23.58). Trace metals may affect pubertal breast density at varying developmental stages with implications for increased susceptibility for breast cancer. [ABSTRACT FROM AUTHOR]

The purpose of the study was to determine whether running is associated with greater bone mineral density (BMD) by comparing the BMD of regularly active male runners (AR) with inactive nonrunner male controls (INC). This cross-sectional study recruited 327 male AR and 212 male INC (aged 18–65) via a stratified recruitment strategy. BMD of the whole body (WB) and partial segments (spine, lumbar spine (LS), leg, hip, femoral neck (FN), and arm for each side) were measured by dual-energy x-ray absorptiometry (DXA) and lower leg dominance (dominant-D/nondominant-ND) was established by functional testing. An ANCOVA was used to compare AR and INC. The AR had greater BMD for all segments of the lower limb (p<0.05), but similar BMD for all segments of the upper limb (p>0.05) compared with INC. Based on the pairwise comparison of age groups, AR had greater BMD of the ND leg in every age group compared with INC (p<0.05). AR had grater BMD of the D leg in every age group except for (26–35 and 56–65) compare with INC (p<0.05). In the youngest age group (18–25), AR had greater BMD in every measured part of lower extremities (legs, hips, femoral necks) compared with INC (p<0.05). In the 46–55 age group AR had greater BMD than INC (p < 0.05) only in the WB, D Leg, D neck, and ND leg. In the 56–65 age group AR had greater BMD than INC (p<0.05) only in the ND leg. Overall, AR had greater BMD compared with INC in all examined sites except for the upper limbs, supporting the notion that running may positively affect bone parameters. However, the benefits differ in the skeletal sites specifically, as the legs had the highest BMD difference between AR and INC. Moreover, the increase in BMD from running decreased with age. [ABSTRACT FROM AUTHOR]

Objective: To evaluate whether the CT attenuation of bones seen on shoulder CT scans could be used to predict low bone mineral density (BMD) (osteopenia/osteoporosis), and to compare the performance of two machine learning models to predict low BMD. Methods: In this study, we evaluated 194 patients aged 50 years or greater (69.2 ± 9.1 years; 170 females) who underwent unenhanced shoulder CT scans and dual-energy X-ray absorptiometry within 1 year of each other between January 1, 2010, and December 31, 2021. The CT attenuation of the humerus, glenoid, coracoid, acromion, clavicle, first, second, and third ribs was obtained using 3D-Slicer. Support vector machines (SVMs) and k-nearest neighbours (kNN) were used to predict low BMD. DeLong test was used to compare the areas under the curve (AUCs). Results: A CT attenuation of 195.4 Hounsfield Units of the clavicle had a sensitivity of 0.577, specificity of 0.781, and AUC of 0.701 to predict low BMD. In the test dataset, the SVM had sensitivity of 0.686, specificity of 1.00, and AUC of 0.857, while the kNN model had sensitivity of 0.966, specificity of 0.200, and AUC of 0.583. The SVM was superior to the CT attenuation of the clavicle (P = .003) but not better than the kNN model (P = .098). Conclusion: The CT attenuation of the clavicle was best for predicting low BMD; however, a multivariable SVM was superior for predicting low BMD. Advances in knowledge: SVM utilizing the CT attenuations at many sites was best for predicting low BMD. [ABSTRACT FROM AUTHOR]

Objective To observe the distribution and changes of trabecular bone score (TBS) in the population of Chengdu region. To evaluate the precision of TBS for monitoring osteoporosis treatment. Methods A total of 4 963 patients， including 3 708 females and 1 255 males were selected from October 2022 to July 2023. Dual energy X-ray Absorptiometry (DXA) examination were performed to measure lumbar BMD and TBS.The results were expressed as mean ± standard deviation (SD). 30 patients were selected to undergo two DXA examinations each.The precision errors of BMD and TBS were calculated. Results ①The TBS reaches its peak in males aged 20-29 and females aged 30-39, and Gradually decreases with age thereafter. ② TBS were negatively correlated with age and weakly positively correlated with BMI both in male and female. TBS was positively correlated with L1-4 BMD. ③Theproportion of degraded TBS in male and female in low bone mass group were 19.6 % and 35.1 %, respectively；The proportion of degraded or partially degraded TBS in men and women with normal BMD were 22.9 % and 40.5 %，respectively. The CV % and LSC-CV % of L1-4 BMD were 1.089 % and 3.015 %，respectively；and in TBS were 1.429 % and 3.958 %, respectively. Conclusion ①This group of TBS data provided a reference basis for treatment of osteoporosis and the risk assessment of fractures for the population in Chengdu region. BMD and TBS gradually losed with age，especially in women. ②TBS has good precision and can be used for monitoring the treatment of osteoporosis. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to evaluate differences in the pattern of fixation with a rectangular tapered short stem (Fitmore stem) due to proximal femoral medullary cavity morphology based on periprosthetic bone mineral density (BMD) and radiological findings. Materials and methods: We analyzed 105 consecutive patients (Dorr type A, 18; Dorr type B, 66; Dorr type C, 21) who underwent total hip arthroplasty using a Fitmore stem. Periprosthetic BMD was measured using dual-energy X-ray absorptiometry from 1 to 24 months postoperatively and radiological analysis was performed. Clinical outcomes were evaluated using the Harris hip score (HHS) and the University of California Los Angeles (UCLA) activity score preoperatively and 24 months postoperatively. Results: At 24 months postoperatively, Dorr type C had significantly decreased BMD changes in Gruen zones 2, 6, and 7 compared to Dorr types A and B, and conversely, significantly increased BMD changes in zone 4 (p < 0.05). Dorr type C had significantly greater subsidence than the other types (p < 0.01) and significantly higher cortical hypertrophy in zone 3 (p < 0.01). Stress shielding was not significantly different between Dorr types. The preoperative and postoperative HHS and UCLA activity scores showed no significant differences between the Dorr types. Conclusions: In Dorr type C, BMD significantly decreased in the proximal femur with a rectangular tapered short stem, suggesting that the stem was fixed at the distal part. Careful observation of this prosthesis over time is needed in patients with Dorr type C. [ABSTRACT FROM AUTHOR]