Bone Mineral Density Variation Research Articles

Association between triglycerides and lumbar bone mineral density in Chinese patients with osteoporotic fractures: a retrospective cross-sectional study

The association between lumbar bone mineral density (BMD) and triglyceride (TG) levels has been extensively studied; however, the results remain controversial. Therefore, this research aimed to elucidate the association of TG levels with lumbar BMD in patients with osteoporotic fractures (OPFs) who have undergone surgery. This cross-sectional study analyzed 3,558 OPF patients (aged 50 years and above) who were admitted to the First People’s Hospital of Kunshan and assessed their TG levels, lumbar BMD, and other variables. The outcome variable of this research was bone density, whereas the baseline glycerol trihydrate levels were considered as the exposure variable. An analysis adjustment was conducted for various covariates, including age, gender, body mass index (BMI), and other baseline laboratory and clinical results. Furthermore, the potential non-linear relationships were assessed via the smooth curve fitting, and threshold effect analyses. The mean age of 3,558 included OPF patients was 68.87 ± 10.55 years. In the fully adjusted multivariate regression analysis, a positive correlation was found between TG levels and lumbar BMD (β = 0.015, 95% CI: 0.001–0.028, p = 0.033). Furthermore, the threshold effect analysis revealed a curvilinear relationship between TG levels and lumbar BMD, with a turning point at 1.26 mmol/L. Moreover, on both sides of the turning point, different patterns were observed. On the left side, TG levels were positively correlated with lumbar BMD. However, despite higher TG levels, the differences in lumbar BMD on the right side of the turning point, were not statistically significant, indicating a lack of significant association (p = 0.712). In summary, this research indicated that in OPF patients, higher TG levels were significantly positively associated with lumbar BMD. Furthermore, there was a threshold value of 1.26 mmol/L, indicating that TG levels in OPF patients with concomitant hypertriglyceridemia should be maintained within the normal range, and reducing TG levels below 1.26 mmol/L requires continuous monitoring. This approach effectively controls TG levels without adversely impacting lumbar BMD.

Bone Mineral Density in the Scaphoid.

Introduction: The scaphoid bone is essential for wrist stability and movement. While fractures commonly occur at the scaphoid's waist, those at the proximal pole, though rarer, tend to result in nonunion, potentially linked to variations in bone mineral density (BMD). Previous studies have shown an increase in BMD at the proximal pole in fractured scaphoids, but BMD distribution in intact scaphoids has not been well studied. This study aims to map the BMD distribution of the intact scaphoid to better understand the etiology of fractures and optimize treatment approaches. Methods: Conducted under ethical approval, this study included 100 individuals, using computed tomography to assess the BMD in distal, middle, and proximal thirds of the scaphoid. Measurements were performed in the defined regions and analyzed using SPSS software, with significance accepted at P < .05. Results: The study comprised 34 females and 66 males, with no significant BMD difference between the right and left wrists. The proximal third exhibited significantly higher BMD (542.2 HU) compared to the middle (293.1 HU) and distal thirds (298.4 HU). A statistically significant higher BMD was observed in males, particularly in the proximal and distal thirds. A weak negative correlation between age and BMD was noted across all sections. Conclusion: The proximal scaphoid shows significantly higher BMD, potentially explaining its lower fracture incidence but higher nonunion rate. This insight into the BMD distribution within an intact scaphoid may guide the clinical management of scaphoid fractures, highlighting the need for targeted treatment strategies based on BMD variations.

From gut to bone: deciphering the impact of gut microbiota on osteoporosis pathogenesis and management.

Osteoporosis (OP) is characterized by decreased bone mineral density (BMD) and increased fracture risk, poses a significant global health burden. Recent research has shed light on the bidirectional relationship between gut microbiota (GM) and bone health, presenting a novel avenue for understanding OP pathogenesis and developing targeted therapeutic interventions. This review provides a comprehensive overview of the GM-bone axis, exploring the impact of GM on OP development and management. We elucidate established risk factors and pathogenesis of OP, delve into the diversity and functional changes of GM in OP. Furthermore, we examine experimental evidence and clinical observations linking alterations in GM composition or function with variations in BMD and fracture risk. Mechanistic insights into microbial mediators of bone health, such as microbial metabolites and products, are discussed. Therapeutic implications, including GM-targeted interventions and dietary strategies, are also explored. Finally, we identify future research directions and challenges in translating these findings into clinical practice.

Impact of altitude on the development of low bone mineral density and osteoporosis in individuals aged 50 years and older: protocol for a multicentre prospective cohort study

IntroductionOsteoporotic fractures are a leading cause of disability and contribute significantly to medical care costs worldwide. Variations in bone mineral density and the risk of osteoporosis are notably influenced by...

Genomic structural variations link multiple genes to bone mineral density in a multi-ethnic cohort study: Louisiana osteoporosis study.

Osteoporosis, characterized by low BMD, is a highly heritable metabolic bone disorder. Although single nucleotide variations (SNVs) have been extensively studied, they explain only a fraction of BMD heritability. Although genomic structural variations (SVs) are large-scale genomic alterations that contribute to genetic diversity in shaping phenotypic variations, the role of SVs in osteoporosis susceptibility remains poorly understood. This study aims to identify and prioritize genes that harbor BMD-related SVs. We performed whole genome sequencing on 4982 subjects from the Louisiana Osteoporosis Study. To obtain high-confidence SVs, the detection of SVs was performed using an ensemble approach. The SVs were tested for association with BMD variation at the hip (HIP), femoral neck (FNK), and lumbar spine (SPN), respectively. Additionally, we conducted co-occurrence analysis using multi-omics approaches to prioritize the identified genes based on their functional importance. Stratification was employed to explore the sex- and ethnicity-specific effects. We identified significant SV-BMD associations: 125 for FNK-BMD, 99 for SPN-BMD, and 83 for HIP-BMD. We observed SVs that were commonly associated with both FNK and HIP BMDs in our combined and stratified analyses. These SVs explain 13.3% to 19.1% of BMD variation. Novel bone-related genes emerged, including LINC02370, ZNF family genes, and ZDHHC family genes. Additionally, FMN2, carrying BMD-related deletions, showed associations with FNK or HIP BMDs, with sex-specific effects. The co-occurrence analysis prioritized an RNA gene LINC00494 and ZNF family genes positively associated with BMDs at different skeletal sites. Two potential causal genes, IBSP and SPP1, for osteoporosis were also identified. Our study uncovers new insights into genetic factors influencing BMD through SV analysis. We highlight BMD-related SVs, revealing a mix of shared and specific genetic influences across skeletal sites and gender or ethnicity. These findings suggest potential roles in osteoporosis pathophysiology, opening avenues for further research and therapeutic targets.

Association between triglyceride-glucose index and femoral bone mineral density in community-dwelling, nondiabetic men and women: a NHANES analysis of 1,928 US individuals.

To determine the potential association between the triglyceride-glucose (TyG) index and bone mineral density (BMD) in community-dwelling adults without diabetes using a nationally representative database from the United States (US). Data were extracted from the National Health and Nutrition Examination Survey (NHANES) 2005-2010, 2013-2014, and 2017-2018. Men and postmenopausal women aged ≥50 years with complete data on femoral neck BMD, triglycerides, and fasting plasma glucose levels were eligible for inclusion. Participants with diabetes, history of malignancy, thyroid disease, underweight status, end-stage kidney disease, rheumatoid arthritis, estrogen/selective estrogen receptor modulators, bisphosphonate or bone resorption inhibitors, or missing dataset weight values were excluded. Univariate and multivariable logistic regression analyses were performed to determine the associations between low BMD, TyG index, and other study variables. A total of 1,844 participants (1,161 men and 683 women) were included, representing 31,517,106 community-dwelling individuals in the US. The mean age of the study population was 60.7 years old, and 26.7% of the men and 60.4% of the women had low bone density. In both males and females, the mean TyG index was 8.6. After adjusting for demographic, lifestyle, and clinical factors, no significant association was observed between TyG and femoral neck BMD among men (adjusted odds ratio [aOR] = -0.0002, 95% confidence interval [CI]: -0.02 to 0.02) and women (aBeta = 0.005, 95% CI: -0.02 to 0.04). Similarly, no significant association was observed between TyG index and the odds for low bone density among men (aOR = 1.09, 95% CI: 0.73-1.63) and women (aOR = 0.99, 95% CI: 0.49-2.01). Based on data from a large sample in the US, this study did not find an association between the TyG index and femoral neck BMD or the occurrence of low bone density in community-dwelling males and females without diabetes.

Assessment of the relationship between gut microbiota and bone mineral density: a two-sample Mendelian randomization study.

Emerging evidence from observational studies and clinical trials suggests a connection between the gut microbiota and variations in bone mineral density (BMD). Nonetheless, the specific association between gut microbiota and BMD alterations at different skeletal sites has not been comprehensively explored. To address this, we employed Genome-Wide Association Study (GWAS) summary statistics from a publicly accessible database, conducting a two-sample Mendelian Randomization analysis to elucidate the potential causal relationship between gut microbiota composition and BMD. This study utilized two distinct thresholds for screening instrumental variables (IVs), followed by an extensive series of quality control procedures to identify IVs that were significantly related to exposure. Gut microbiota were classified into two sets based on hierarchical levels: phylum, class, order, family, and genus. Bone mineral density (BMD) data were systematically collected from four skeletal sites: femoral neck, lumbar spine, forearm, and heel. For Mendelian Randomization (MR) analysis, robust methods including Inverse-Variance Weighting (IVW) and the Wald Ratio Test were employed. Additional analytical tests such as the Outlier Test, Heterogeneity Test, 'Leave-One-Out' Test, and Pleiotropy Test were conducted to assess the impact of horizontal pleiotropy, heterogeneities, and the genetic variation stability of gut microbiota on BMD causal associations. The MR Steiger Directionality Test was applied to exclude studies with potential directional biases. In this two-sample Mendelian randomization analysis, we utilized five sets of exposure GWAS (Genome-Wide Association Studies) summary statistics and four sets of outcome GWAS summary statistics. The initial analysis, applying a threshold of p < 5 × 10-6, identified 48 significant causal relationships between genetic liability in the gut microbiome and bone mineral density (BMD). A subsequent analysis with a more stringent threshold of p < 5 × 10-8 uncovered 14 additional causal relationships. Upon applying the Bonferroni correction, 9 results from the first analysis and 10 from the second remained statistically significant. Our MR analysis revealed a causal relationship between gut microbiota and bone mineral density at all sites, which could lead to discoveries in future mechanistic and clinical studies of microbiota-associated osteoporosis.

Farnesyl Diphosphate Synthase Gene Associated with Loss of Bone Mass Density and Alendronate Treatment Failure in Patients with Primary Osteoporosis.

Aminobisphosphonates (NBPs) are the first-choice medication for osteoporosis (OP); NBP treatment aims at increasing bone mineral density (BMD) by inhibiting the activity of farnesyl diphosphate synthase (FDPS) enzyme in osteoclasts. Despite its efficacy, inadequate response to the drug and side effects have been reported. The A allele of the rs2297480 (A > C) SNP, found in the regulatory region of the FDPS gene, is associated with reduced gene transcription. This study evaluates the FDPS variant rs2297480 (A > C) association with OP patients' response to alendronate sodium treatment. A total of 304 OP patients and 112 controls were enrolled; patients treated with alendronate sodium for two years were classified, according to BMD variations at specific regions (lumbar spine (L1-L4), femoral neck (FN) and total hip (TH), as responders (OP-R) (n = 20) and non-responders (OP-NR) (n = 40). We observed an association of CC genotype with treatment failure (p = 0.045), followed by a BMD decrease in the regions L1-L4 (CC = -2.21% ± 2.56; p = 0.026) and TH (CC = -2.06% ± 1.84; p = 0.015) after two years of alendronate sodium treatment. Relative expression of the FDPS gene was also evaluated in OP-R and OP-NR patients. Higher expression of the FDPS gene was also observed in OP-NR group (FC = 1.84 ± 0.77; p = 0.006) when compared to OP-R. In conclusion, the influence observed of FDPS expression and the rs2897480 variant on alendronate treatment highlights the importance of a genetic approach to improve the efficacy of treatment for primary osteoporosis.

Body composition analysis using dual-energy x-ray absorptiometry in an Egyptian pediatric sickle cell disease cohort.

Growth failure is commonly encountered in sickle cell disease (SCD). Tissue compartment growth and development are subsequently likely to be altered in such patients. We aimed to analyze body composition in an Egyptian pediatric SCD cohort using dual-energy x-ray absorptiometry (DEXA), one of the most comprehensive and noninvasive assessment methods available. Forty children with SCD ≤18years and 40 healthy youngsters age- and gender-matched were enrolled. Patients' demographic, clinical, and laboratory parameters were obtained from their archived files. All patients and controls were subjected to body composition assessment using a MedixDR-Whole Body DEXA System. In SCD patients; weight and height relative to age Z scores were significantly lower (p<.001), total body lean was significantly higher (p=.006), and total body fat percentage was lower, yet the difference was not statistically significant (p=.09). There were no statistically significant variations in bone mineral density or content, basal metabolic rate, subcutaneous adipose tissue, android/gynoid fat ratio, and visceral adipose tissue. There were no significant gender disparities between SCD patients and controls. Faltering growth in children with SCD should be addressed with a multidisciplinary approach including nutritional support, correction of anemia, and proper medical care. Body composition parameters assessed using DEXA were comparable between cases and controls apart from total body lean. Further clinical studies are needed with multicenter cooperation and a larger sample size to assess the usefulness of DEXA as an assessment tool for body composition in children with SCD.

Interaction between MARK3 (rs11623869), PLCB4 (rs6086746) and GEMIN2 (rs2277458) variants with bone mineral density and serum 25-hidroxivitamin D levels in Mexican Mestizo women.

Understanding the genetic factors contributing to variations in bone mineral density (BMD) and vitamin D could provide valuable insights into the pathogenesis of osteoporosis. This study aimed to evaluate the association of single nucleotide variants in MARK3 (rs11623869), PLCB4 (rs6086746), and GEMIN2 (rs2277458) with BMD in Mexican women. The gene-gene interaction was evaluated in these variants in serum 25(OH)D levels and BMD. A genetic risk score (GRS) was created on the basis of the three genetic variants. Genotyping was performed using predesigned TaqMan assays. A significant association was found between the rs6086746-A variant and BMD at the total hip, femoral neck, and lumbar spine, in women aged 45 years or older. However, no association was observed between the variants rs11623869 and rs2277458. The rs11623869 × rs2277458 interaction was associated with total hip (p=0.002) and femoral neck BMD (p=0.013). Similarly, for vitamin D levels, we observed an interaction between the variants rs6086746 × rs2277458 (p=0.021). GRS revealed a significant association with total hip BMD (p trend=0.003) and femoral neck BMD (p trend=0.006), as well as increased vitamin D levels (p trend=0.0003). These findings provide evidence of the individual and joint effect of the MARK3, PLCB4, and GEMIN2 variants on BMD and serum vitamin D levels in Mexican women. This knowledge could help to elucidate the interaction mechanism between BMD-related genetic variants and 25OHD, contributing to the determination of the pathogenesis of osteoporosis and its potential implications during early interventions.

Quantitative computed tomography assessment of bone mineral density in adolescent idiopathic scoliosis: correlations with Cobb angle, vertebral rotation, and Risser sign.

Adolescent idiopathic scoliosis (AIS) is a prevalent spinal disorder that can potentially influence bone mineral density (BMD), thereby increasing the susceptibility to osteoporosis and fractures. Early identification of reduced bone mass in AIS patients is crucial for clinicians to develop effective preventive strategies against fractures. This study aims to elucidate the correlation between BMD, as measured by quantitative computed tomography (QCT), and various clinical parameters in AIS, including the Cobb angle, vertebral rotation, and the Risser sign. By revealing the potential influences of these factors on BMD, our findings aim to assist clinicians in making informed and timely decisions regarding AIS management, particularly in situations where QCT is unavailable. A cross-sectional study was conducted on 129 adolescents with AIS who were enrolled at The Third People's Hospital of Chengdu, Sichuan, China, between 2021 and 2023. QCT was employed to assess BMD and vertebral rotation. The Cobb angle and Risser sign were determined through radiographic evaluation, while anthropometric and biochemical data were also collected. Statistical analyses, including Pearson and Spearman rank correlation and regression models, were used to investigate the associations between BMD and clinical measures. A significant negative correlation was found between BMD and Cobb angle (coefficient =-0.663; P<0.001), as well as between BMD and vertebral rotation angle (coefficient =-0.442; P<0.001) in patients with AIS. BMD was positively correlated with increased height (coefficient =0.355; P<0.001) and BMI (coefficient =0.199; P=0.02). A significant association was detected between BMD and the Risser sign (P=0.002). No significant sex-based differences in BMD were observed (P=0.052). No significant correlations were observed between BMD and levels of potassium (K), calcium (Ca), inorganic phosphate (P), and iron (Fe) (P>0.05 all). The binary logistic regression analysis identified Cobb angle as a risk factor of lower BMD presence in AIS patients (coefficient =0.072; OR=1.075; P<0.001). Furthermore, the receiver operating characteristic (ROC) analysis of the combined model for predicting low BMD in AIS patients yielded an area under the curve (AUC) value of 0.900, with an optimal threshold determined as 0.398. The sensitivity and specificity were calculated as 0.816 and 0.900, respectively, indicating a robust predictive capacity. This study highlights the significant inverse correlation observed between BMD measured by QCT and both Cobb angle and vertebral rotation angle in patients with AIS. Furthermore, a notable variation in BMD was found across different Risser sign categories, with BMD values generally increasing as Risser sign levels increased. Additionally, our findings indicate that Cobb angle serves as a risk factor for low BMD presence. Moreover, a combined model was developed to predict the likelihood of low BMD occurrence in AIS patients.

Patterns of age- and sex-related variations in bone mineral density of total spine by selected demographic and socioeconomic variables

Patterns of age- and sex-related variations in bone mineral density of total spine by selected demographic and socioeconomic variables

Salivary Calprotectin Levels and Bone Mineral Density in Post-Menopausal Women With and Without Chronic Periodontitis - An Evaluative Study.

Menopause is a normal developmental stage in a woman's life marking the permanent cessation of menstruation. Periodontitis and osteoporosis are noteworthy health concerns in post-menopausal women. Calprotectin is an inflammatory biomarker for precise diagnosis of periodontal disease. This study was performed to evaluate the variations in salivary calprotectin levels and bone mineral density in post-menopausal women with and without chronic periodontitis. The study included 24 post-menopausal women aged 45-57 years and was divided into group 1 (12 post-menopausal women without chronic periodontitis) and group 2 (12 post-menopausal women with chronic periodontitis). Unstimulated salivary samples, panoramic radiographs and clinical examination were performed. The collected samples were combined with CALPRO antibody with horseradish peroxide (HRP) that results in the formation of antigen-antibody complex. Tetramethylbenzidine (TMB) solution was added that turned blue. Colour change was measured at 450nm. A human ELISA kit was used. Data collected were sent for statistical analysis. There was a statistically significant difference in salivary calprotectin levels between groups 1 and 2 ( P = 0.016) and no statistical difference in mean bone mineral density levels between the two groups ( P = 0.235). A positive correlation was seen between salivary calprotectin levels and bone mineral density in group 2 ( P = 0.013).

Effects of exercise training on bone health in adults living with HIV: a systematic review with meta-analysis

ABSTRACT We investigated the effects of exercise training on bone mineral density (BMD) in people living with Human Immunodeficiency Virus (PLHIV). Pubmed, Scopus, Cochrane Library, and ScienceDirect databases were searched for trials investigating exercise training-induced changes in BMD of PLHIV at baseline vs. post-intervention assessed by dual-energy X-ray absorptiometry (DXA). Hedge effect sizes (ES) were calculated incorporating fixed effects for BMD variation assumptions. Disaggregated comparisons were performed for trials with more than one intervention or BMD site assessment. Seven trials included 210 PLHIV and 35 non-HIV-infected controls. Methodological quality evaluated using the Physiotherapy Evidence Database (PEDro) scale ranged from poor to moderate. Interventions applied isolated resistance, combined aerobic and resistance, and multimodal exercise protocols performed 3 d/wk for 12-to 104 week. One controlled and another uncontrolled trial presented significant effects, reporting improvements at the femoral neck and total (ES 2.14 and 0.49, respectively). Magnitude of those specific ES influenced the overall effect (controlled and uncontrolled trials), which was small but significant (k = 12, ES 0.277, 95% confidence interval 0.120-0.434). Resistance training may promote favorable adaptations in BMD of PLHIV, particularly in femur. Future research should elucidate the optimal dose-response relationship and physiological mechanisms underlying exercise-induced adaptations on the BMD of PLHIV.

Differences in Vertebral Morphology and bone Mineral Density between Grade 1 Vertebral Fracture and Non-Fractured Participants in the Chinese Population.

To investigate the difference in vertebral morphology and bone mineral density (BMD) between grade 1 VFs and non-fractured participants in the Chinese population to shed light on the clinical significance of grade 1 VFs from various perspectives. This retrospective cohort study included patients who received a chest low-dose computed tomography (LDCT) scan for health examination and visited the First Affiliated Hospital of Zhengzhou University, Henan, China, from October 2019 to August 2022. Data were analyzed from March 2023 to July 2023. The main outcome of this study was the difference in morphological parameters and BMD between grade 1 VFs and non-fractured participants. The prevalence of grade 1 VFs in China populations was calculated. The difference in BMD of three fracture types in the Grade 1 group was also evaluated. A total of 3652 participants (1799 males,54.85 ± 9.02 years, range, 40-92 years; 1853 females, 56.00 ± 9.08 years, range, 40-93 years) were included. The prevalence of grade 2 and 3 increase with age. The prevalence of grade 1 VFs gradually increases ≤ 50y to 60-69y group, but there is a decrease in the ≥ 70 years male group (6.6%) and a rise in the female group (25.5%). There was no significant statistical difference observed in vertebral shape indices (VSI) and BMD between the Grade 1 group and the no-fractured group aged < 50 years old except the wedge index in male. The biconcavity index did not differ between the non-fractured group and the Grade 1 group in men aged 50-59 years, whereas a significant statistical difference was observed in women. Additionally, the results of BMD were consistent with these findings. For the 40-59 years age group, there were significant differences between the compression deformity group and the other groups. The grade 1 group had higher VSI and lower BMD than the non-fractured group, suggesting an association between the Grade 1 group and osteoporosis in individuals aged over 50 for women and over 60 for men. Different fracture types have significant variations in BMD among middle-aged people. The prevalence of grade 1 VFs exhibits an age-related increase in both genders, with opposite trends observed between older males and females. We suggested VSI can aid physicians in the diagnosis of grade 1 VFs.

Quantitative Analysis of Age-Associated Bone Mineral Density Variations via Automated Segmentation: Using CT Scans and Radon Transform to Accurately Examine and Assess the Vertebrae

Quantitative Analysis of Age-Associated Bone Mineral Density Variations via Automated Segmentation: Using CT Scans and Radon Transform to Accurately Examine and Assess the Vertebrae

Geographic variation in bone mineral density and prevalent fractures in the Canadian longitudinal study on aging.

We aimed to describe sex-specific total hip bone mineral density (aBMD) and prevalent major osteoporotic fractures (MOF) variation between Canadian provinces. We used baseline data from 21,227 Canadians (10,716 women, 10,511 men) aged 50-85 years in the Canadian Longitudinal Study on Aging (CLSA; baseline: 2012-2015). Linear and logistic regression models were used to examine associations between province of residence and total hip aBMD and self-reported MOF, stratified by sex. CLSA sampling weights were used to generate the prevalence and regression estimates. The mean (SD) age of participants was 63.9 (9.1) years. The mean body mass index (kg/m2) was lowest in British Columbia (27.4 [5.0]) and highest in Newfoundland and Labrador (28.8 [5.3]). Women and men from British Columbia had the lowest mean total hip aBMD and the lowest prevalence of MOF. Alberta had the highest proportion of participants reporting recent falls (12.0%), and Manitoba (8.4%) the fewest (p-value=0.002). Linear regression analyses demonstrated significant differences in total hip aBMD: women and men from British Columbia and Alberta, and women from Manitoba and Nova Scotia had lower adjusted total hip aBMD than Ontario (p-values<0.02). Adjusted odds ratios (95% confidence intervals, CI) for prevalent MOF were significantly lower in women from British Columbia (0.47 [95% CI: 0.32; 0.69]) and Quebec (0.68 [95% CI: 0.48; 0.97]) and in men from British Columbia (0.40 [95% CI:0.22; 0.71]) compared to Ontario (p-values<0.03). Results were similar when adjusting for physical performance measures and when restricting the analyses to participants who reported White race/ethnicity. Geographical variations in total hip aBMD and in the prevalence of MOF between provinces persisted after adjusting for important covariates which suggests an association with unmeasured individual and environmental factors.

Construction of a Viscoelastic Model of Human Cancellous Bone in Alveolar Bone Based on Bone Mineral Density Distribution

Orthodontic treatment was accompanied by the remodeling of cancellous bone in alveolar bone (CBAB), which manifested as the increase or decrease in bone mineral density (BMD). BMD is closely related to the mechanical properties of the alveolar bone. Therefore, the aim of this study was to quantify the effect of BMD on its viscoelastic behavior and to assess orthodontic forces at different BMDs. A total of nine CBAB samples were cut from the cervical, middle, and apical regions of the right mandible between canine, premolars, and molars. After scanning with micro-computed tomography (micro-CT). The BMD of samples was measured and dynamic mechanical analysis (DMA) was performed. Based on the fourth-order generalized Maxwell model, a viscoelastic constitutive model characterizing the BMD variation was constructed. The BMD exhibited variations within different regions of the CBAB. The storage modulus is positively correlated with BMD, and the loss modulus is negatively correlated with BMD.

The Interplay between Muscular Grip Strength and Bone Mineral Density with Consideration of Metabolic and Endocrine Parameters in Individuals with Turner Syndrome.

Patients with Turner syndrome (TS) often face skeletal and muscular challenges, including reduced bone mineral density (BMD) and muscle weakness. This comprehensive study sheds light on the complex interplay between muscle strength, BMD, and metabolic and endocrine parameters in TS and healthy subjects. A cross-sectional study involving 42 TS patients and 70 healthy women was conducted. All patients had their BMD determined in the L1-L4 lumbar spine section and in the whole skeleton as well as the parameters of body fat mass (BF), and visceral fat mass (VF) were also determined. The maximum gripping force was measured with a hydraulic manual dynamometer. In addition, a number of blood hormonal and metabolic parameters were determined. In the TS group, hand grip strength correlated positively with triglyceride levels but not with BMD. Healthy individuals had a positive link between hand grip strength and BMD, while patients with TS did not show a significant association between the two. A trend suggested that longer recombinant human growth hormone (rhGH) therapy might improve BMD in the L1-L4 region. Multiple linear regression analysis revealed that muscle strength assessment may be a potential exponent of reduced BMD, and also used clinically in young adult women but not in individuals with TS. The relationship between BMD variables and hand grip might differ between the two groups, potentially indicating distinct musculoskeletal characteristics in TS patients. Longer rhGH therapy in TS patients may have a positive effect on BMD in the L1-L4 region. Understanding the intricate relationships between these factors is important for optimizing clinical management strategies and improving the quality of life for TS patients.

High prevalence of low bone mineral density but normal trabecular bone score in Norwegian elite Para athletes.

Low bone mineral density (BMD) increases the risk of bone stress injuries (BSI) and is one of several clinical concerns in Para athlete sports medicine. However, whether bone microarchitecture is altered in Para athletes is not known. We aimed to investigate BMD, bone microarchitecture and incidence of bone stress injuries in Norwegian elite Para athletes. In this cross-sectional study in Para athletes, Dual energy x-ray absorptiometry (iDXA, Lunar, GE Health Care) derived areal BMD, trabecular bone score (TBS), a surrogate marker for bone microarchitecture, and body composition (body weight (BW), lean body mass (LBM), fat mass (FM), fat percentage) were investigated and compared between ambulant and non-ambulant athletes. Also, the association between BMD, TBS and body composition variables was investigated. Incidence of BSI was assessed with a questionnaire and confirmed by a sports physician in a clinical interview. BMD Z-score <-1 was defined as low and ≤-2 as osteoporotic. TBS ≥ 1.31 was normal, 1.23-1.31 intermediate and <1.23 low. Among 38 athletes (26 ± 6 yrs, 14 females), BMD Z-score was low in 19 athletes, and osteoporotic in 11 athletes' lumbar spine (LS) or femoral neck (FN). BMD was lower in non-ambulant vs. ambulant athletes both in LS (1.13 ± 0.19 vs. 1.25 ± 0.14 g/cm2, p = 0.030) and FN (0.90 ± 0.15 vs. 1.07 ± 0.16 g/cm2, p = 0.003). TBS was normal for all athletes. BMD Z-score in LS was positively associated with TBS (r = 0.408, p = 0.013), body weight (r = 0.326, p = 0.046) and lean body mass (r = 0.414, p = 0.010), but not with fat mass or fat percentage. None of the athletes reported any BSI. Half of the Norwegian elite Para athletes had low BMD, and 29% had BMD Z-score <-2 suggesting osteoporosis. Non-ambulant athletes were more prone to low BMD than ambulant athletes. However, despite high prevalence of low BMD, TBS was normal in all athletes, and BSI was absent in this young population.