Estrogens and Androgens in Skeletal Physiology and Pathophysiology.

Estrogens and androgens influence the growth and maintenance of the mammalian skeleton and are responsible for its sexual dimorphism. Estrogen deficiency at menopause or loss of both estrogens and androgens in elderly men contribute to the development of osteoporosis, one of the most common and impactful metabolic diseases of old age. In the last 20 years, basic and clinical research advances, genetic insights from humans and rodents, and newer imaging technologies have changed considerably the landscape of our understanding of bone biology as well as the relationship between sex steroids and the physiology and pathophysiology of bone metabolism. Together with the appreciation of the side effects of estrogen-related therapies on breast cancer and cardiovascular diseases, these advances have also drastically altered the treatment of osteoporosis. In this article, we provide a comprehensive review of the molecular and cellular mechanisms of action of estrogens and androgens on bone, their influences on skeletal homeostasis during growth and adulthood, the pathogenetic mechanisms of the adverse effects of their deficiency on the female and male skeleton, as well as the role of natural and synthetic estrogenic or androgenic compounds in the pharmacotherapy of osteoporosis. We highlight latest advances on the crosstalk between hormonal and mechanical signals, the relevance of the antioxidant properties of estrogens and androgens, the difference of their cellular targets in different bone envelopes, the role of estrogen deficiency in male osteoporosis, and the contribution of estrogen or androgen deficiency to the monomorphic effects of aging on skeletal involution.

Health-related quality of life in osteoporosis: a systematic review of measurement properties of the QUALEFFO-41.

The 41-item Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO-41) is a widely used and freely available patient-reported outcome measure (PROM). However, data on its reliability, validity, and responsiveness remain unclear. Therefore, this study aimed to systematically review the measurement properties of the QUALEFFO-41. A systematic search of MEDLINE, EBSCOhost, and Cochrane Library from their inception up to December 2022 was performed. Data were extracted, and the methodological quality of each measurement property was evaluated according to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines. The evidence of the measurement properties was rated against the updated criteria for good measurement properties, and the quality of evidence was graded using the modified GRADE approach. A total of 99 articles were identified, of which eight studies were included in the review. The QUALEFFO-41 is categorized as B as it demonstrated moderate quality evidence for sufficient content validity, moderate-to-high quality evidence for sufficient hypothesis testing for construct validity (except for the social function domain for convergent validity), and very low-quality evidence for sufficient responsiveness. For structural validity and internal consistency, only the domains of pain and general health perception were sufficient with low-quality evidence. For reliability, only the domain of physical function was sufficient with low-quality evidence. None of the studies reported measurement error, cross-cultural validity, and criterion validity. The QUALEFFO-41 may be a promising, valid, and reliable PROM to assess HRQoL in osteoporosis patients with vertebral fractures. However, future studies must focus on good methodological quality to strengthen the evidence of measurement properties, especially on structural validity, reliability, responsiveness, and cross-cultural validity. The systematic review evaluated the measurement properties of the QUALEFFO-41 questionnaire for assessing Health-Related Quality of Life (HRQoL) in osteoporosis patients. The review found moderate-to-high-quality evidence for construct validity but limited evidence for responsiveness and other properties. Future studies should focus on strengthening the evidence, particularly for structural validity, reliability, responsiveness, and cross-cultural validity. The QUALEFFO-41 shows promise as a valid and reliable PROM for HRQoL assessment in osteoporosis patients.

Higher prevalence of thyroid-specific autoantibodies (TPOAb and TgAb) is related to a higher prevalence of fractures in females: results from NHANES 2007-2010.

A retrospective analysis was conducted using data from the NHANES. Bone mineral density (BMD) was compared in different thyroid-specific autoantibodies groups. Strengths of associations were calculated by using binary logistic regression models. Higher titers of thyroid-specific autoantibodies (TgAb and/or TPOAb) may lead to decreased BMD. Higher prevalence of TgAb and TPOAb significantly associated with fractures in females but not in males. PURPOSE: Hashimoto's thyroiditis is characterized by elevated thyroid-specific autoantibodies. It is currently believed that osteoporosis is not only a disease with abnormal mineral metabolism but also with immune abnormalities. This study investigated the relationship between thyroid-specific autoantibodies and osteoporosis, including the bone mineral density (BMD) values and fractures. METHODS: A retrospective analysis was conducted using data from the National Health and Nutrition Examination Survey (2007-2010). BMD was compared in different thyroid-specific autoantibodies groups. The associations between thyroid-specific autoantibodies and fractures were explored. Strengths of associations were calculated by binary logistic regression models. Candidate variables for binary logistic regression model were selected after screened in univariate analysis (variables with P < 0.05). RESULTS: A total of 3865 study participants were included in this analysis; 224 participants were TgAb positive and 356 were TPOAb positive. A total of 392 participants reported hip, spine or wrist fractures. Participants with higher prevalence of TgAb or TPOAb had lower BMD. In females, significant cigarettes use, higher prevalence of TgAb and TPOAb, and the BMD of the total femur and femoral neck were significantly associated with fractures. Higher prevalence of TPOAb was particularly associated with a higher possibility of hip or spine fractures. In males, significant cigarettes use, 25OHD3, the BMD values of the total femur, femoral neck and total spine were significantly associated with fractures. CONCLUSION: Higher prevalence of thyroid-specific autoantibodies may lead to decreased BMD. In females, higher prevalence of TgAb and TPOAb significantly associated with fractures and TPOAb especially relating to the fractures of hip and spine. Males patients with vitamin D deficiency or insufficiency associated a higher possibility of fractures.

Impact of osteoporosis and osteoporosis medications on fracture healing: a narrative review.

Antiresorptive medications do not negatively affect fracture healing in humans. Teriparatide may decrease time to fracture healing. Romosozumab has not shown a beneficial effect on human fracture healing. BACKGROUND: Fracture healing is a complex process. Uncertainty exists over the influence of osteoporosis and the medications used to treat it on fracture healing. METHODS: Narrative review authored by the members of the Fracture Working Group of the Committee of Scientific Advisors of the International Osteoporosis Foundation (IOF), on behalf of the IOF and the Société Internationale de Chirurgie Orthopédique et de Traumatologie (SICOT). RESULTS: Fracture healing is a multistep process. Most fractures heal through a combination of intramembranous and endochondral ossification. Radiographic imaging is important for evaluating fracture healing and for detecting delayed or non-union. The presence of callus formation, bridging trabeculae, and a decrease in the size of the fracture line over time are indicative of healing. Imaging must be combined with clinical parameters and patient-reported outcomes. Animal data support a negative effect of osteoporosis on fracture healing; however, clinical data do not appear to corroborate with this. Evidence does not support a delay in the initiation of antiresorptive therapy following acute fragility fractures. There is no reason for suspension of osteoporosis medication at the time of fracture if the person is already on treatment. Teriparatide treatment may shorten fracture healing time at certain sites such as distal radius; however, it does not prevent non-union or influence union rate. The positive effect on fracture healing that romosozumab has demonstrated in animals has not been observed in humans. CONCLUSION: Overall, there appears to be no deleterious effect of osteoporosis medications on fracture healing. The benefit of treating osteoporosis and the urgent necessity to mitigate imminent refracture risk after a fracture should be given prime consideration. It is imperative that new radiological and biological markers of fracture healing be identified. It is also important to synthesize clinical and basic science methodologies to assess fracture healing, so that a convergence of the two frameworks can be achieved.

A comprehensive meta-analysis of risk factors associated with osteosarcopenic obesity: a closer look at gender, lifestyle and comorbidities.

This study reviewed the risk factors of Osteosarcopenic obesity (OSO), a condition linking weak bones, muscle loss, and obesity. Notable associations were found with female gender, physical inactivity, hypertension, and frailty. Recognizing these early can aid targeted prevention, emphasizing further research for improved understanding and strategies. PURPOSE: Osteosarcopenic obesity (OSO) represents a confluence of osteopenia/osteoporosis, sarcopenia, and obesity, contributing to increased morbidity and mortality risks. Despite escalating prevalence, its risk factors remain under-explored, necessitating this comprehensive systematic review and meta-analysis. METHODS: A diligent search of PubMed, Scopus, and Cochrane databases was conducted for pertinent studies until June 2023. The random-effects model was employed to compute pooled odds ratios (ORs) and 95% confidence intervals (CIs), scrutinizing various risk factors like age, gender, lifestyle factors, and common comorbidities. RESULTS: Our meta-analysis incorporated 21 studies comprising 178,546 participants. We identified significant associations between OSO and factors such as female gender (OR 1.756, 95% CI 1.081 to 2.858), physical inactivity (OR 1.562, 95% CI 1.127-2.165), and hypertension (OR 1.482, 95% CI 1.207-1.821). Conversely, smoking (OR 0.854, 95% CI 0.672-1.084), alcohol consumption (OR 0.703, 95% CI 0.372-1.328), and dyslipidemia (OR 1.345, 95% CI 0.982-1.841) showed no significant associations. Remarkable heterogeneity was observed across studies, indicating considerable variation in effect sizes. Notably, OSO was strongly associated with frailty (OR 6.091; 95% CI 3.576-10.375). CONCLUSIONS: Our study underscored the substantial role of female gender, physical inactivity, and hypertension in the development of OSO, whilst suggesting a strong link between OSO and frailty. These findings emphasize the importance of early risk factor identification and targeted interventions in these groups. Further research is warranted to decode the complex pathophysiological interplay and devise effective prevention and management strategies.

Cross-sectional studies of the causal link between asthma and osteoporosis: insights from Mendelian randomization and bioinformatics analysis.

The study, using data from Chongqing, China, and employing Mendelian randomization along with bioinformatics, establishes a causal link between asthma and osteoporosis, beyond glucocorticoid effects. Asthma may contribute to osteoporosis by accelerating bone turnover through inflammatory factors, disrupting the coupling between osteoblasts and osteoclasts, ultimately leading to osteoporosis. INTRODUCTION: Asthma and osteoporosis are prevalent health conditions with substantial public health implications. However, their potential interplay and the underlying mechanisms have not been fully elucidated. Previous research has primarily focused on the impact of glucocorticoids on osteoporosis, often overlooking the role of asthma itself. METHODS: We conducted a multi-stage stratified random sampling in Chongqing, China and excluded individuals with a history of glucocorticoid use. Participants underwent comprehensive health examinations, and their clinical data, including asthma status, were recorded. Logistic regression and Mendelian randomization were employed to investigate the causal link between asthma and osteoporosis. Furthermore, bioinformatics analyses and serum biomarker assessments were conducted to explore potential mechanistic pathways. RESULTS: We found a significant association between asthma and osteoporosis, suggesting a potential causal link. Mendelian Randomization analysis provided further support for this causal link. Bioinformatics analyses revealed that several molecular pathways might mediate the impact of asthma on bone health. Serum alkaline phosphatase levels were significantly elevated in the asthma group, suggesting potential involvement in bone turnover. CONCLUSION: Our study confirms a causal link between asthma and osteoporosis and highlights the importance of considering asthma in osteoporosis prediction models. It also suggests that asthma may accelerate osteoporosis by increasing bone turnover through inflammatory factors, disrupting the coupling between osteoblasts and osteoclasts, ultimately leading to bone loss.

Semi-automatic proximal humeral trabecular bone density assessment tool: technique application and clinical validation.

PURPOSE: This study aimed to apply a newly developed semi-automatic phantom-less QCT (PL-QCT) to measure proximal humerus trabecular bone density based on chest CT and verify its accuracy and precision. METHODS: Subcutaneous fat of the shoulder joint and trapezius muscle were used as calibration references for PL-QCT BMD measurement. A self-developed algorithm based on a convolution map was utilized in PL-QCT for semi-automatic BMD measurements. CT values of ROIs used in PL-QCT measurements were directly used for phantom-based quantitative computed tomography (PB-QCT) BMD assessment. The study included 376 proximal humerus for comparison between PB-QCT and PL-QCT. Two sports medicine doctors measured the proximal humerus with PB-QCT and PL-QCT without knowing each other's results. Among them, 100 proximal humerus were included in the inter-operative and intra-operative BMD measurements for evaluating the repeatability and reproducibility of PL-QCT and PB-QCT. RESULTS: A total of 188 patients with 376 shoulders were involved in this study. The consistency analysis indicated that the average bias between proximal humerus BMDs measured by PB-QCT and PL-QCT was 1.0 mg/cc (agreement range - 9.4 to 11.4; P > 0.05, no significant difference). Regression analysis between PB-QCT and PL-QCT indicated a good correlation (R-square is 0.9723). Short-term repeatability and reproducibility of proximal humerus BMDs measured by PB-QCT (CV: 5.10% and 3.41%) were slightly better than those of PL-QCT (CV: 6.17% and 5.64%). CONCLUSIONS: We evaluated the bone quality of the proximal humeral using chest CT through the semi-automatic PL-QCT system for the first time. Comparison between it and PB-QCT indicated that it could be a reliable shoulder BMD assessment tool with acceptable accuracy and precision. This study developed and verify a semi-automatic PL-QCT for assessment of proximal humeral bone density based on CT to assist in the assessment of proximal humeral osteoporosis and development of individualized treatment plans for shoulders.

Determination of the Combined Effects of Asian Herbal Medicine with Calcium and/or Vitamin D Supplements on Bone Mineral Density in Primary Osteoporosis: A Systematic Review and Meta-Analysis.

Our review of 52 RCTs from 5 databases suggests a tendency for notable improvement in BMD when combining herbal medicine with supplements (calcium and vitamin D variants) compared to supplement monotherapy in primary osteoporosis. However, caution is needed in interpreting results due to substantial heterogeneity among included studies. PURPOSE: To conduct a systematic review and meta-analysis to determine whether herbal medicine (HM) plus supplements such as calcium (Ca) or vitamin D (Vit.D) improves bone mineral density (BMD) compared to supplements alone in primary osteoporosis (OP) patients. METHODS: We searched 5 databases for randomized controlled trials (RCTs) using HMs with supplements (Ca or Vit.D variants) as interventions for primary OP patients published until August 31, 2022. Meta-analysis using BMD score as the primary outcome was performed using RevMan 5.4 version. Risk of bias in the included studies was assessed useing RoB 2.0 tool. RESULTS: In total, 52 RCTs involving 4,889 participants (1,408 men, 3,481 women) were included, with average BMD scores of 0.690 ± 0.095 g/cm2 (lumbar) and 0.625 ± 0.090 g/cm2 (femoral neck). As a result of performing meta-analysis using BMD scores for all 52 RCTs included in this review, combination of HMs with Ca and Vit.D variants improved the BMD score by 0.08 g/cm2 (lumbar, 38 RCTs, 95% CI: 0.06-0.10, p < 0.001, I2 = 97%) and 0.06 g/cm2 (femoral neck, 19 RCTs, 95% CI: 0.04-0.08, p < 0.001, I2 = 92%)compared to controls. However, statistical significance of the lumbar BMD improvement disappeared after adjusting for potential publication bias. CONCLUSION: Our data suggest that combining of HM and supplements tends to be more effective in improving BMD in primary OP than supplements alone. However, caution is needed in interpretation due to the reporting bias and high heterogeneity among studies, and well-designed RCTs are required in the future.

Different bone health progression patterns and early-stage risk marker in glucocorticoid-treated ambulatory Duchenne muscular dystrophy.

Fractures often cause irreversible harm in Duchenne muscular dystrophy (DMD). This study investigated the trajectory of bone mineral density (BMD) using group-based trajectory modeling and identified that BMD acts as an early-stage indicator of clinically significant bone fragility. The greater the early-stage BMD, the better the 4-year bone health outcome. PURPOSE: Most Duchenne muscular dystrophy (DMD) children suffer bone loss after long-term glucocorticoid (GC) exposure, which induces scoliosis and fragility fractures. To assess the BMD progression pattern and individual medical risk markers for these phenotypes in young ambulatory boys with DMD, and provide evidence-based suggestions for clinical management of bone health. METHODS: A retrospective longitudinal cohort study of 153 boys with DMD in West China Second University Hospital (2016-2023) was performed. Group-based trajectory modeling was used to study the BMD progression pattern, and potential predictors were further analyzed by logistic regression and survival analysis. RESULTS: One hundred and fifty-three participants were included, 71 of which had more than 3 BMD records. Three BMD trajectories were identified. Baseline BMD and age-started GC and were independent predictors of trajectory attribution. The median survival time of the first observation of low BMD in GC-treated DMD boys was 5.32 (95% CI 4.05-6.59) years, and a significant difference was tested (P < 0.001) among the three trajectory groups. CONCLUSION: BMD may serve as a novel early indicating marker for monitoring bone fragility for DMD. We proposed a bone health risk stratification through BMD progression trajectory that allows us to adapt the osteoporosis warning sign in DMD from a fixed threshold approach to a more individualized strategy, where baseline BMD and age of glucocorticoid initiation can provide an earlier prediction of bone loss. Better management of primary BMD may be able to delay or avoid the onset of adverse bone health outcomes in the fifth year in children with DMD.

Key insights into antiresorptive drug use and osteonecrosis in osteoporotic patients undergoing tooth extractions: A clinical and CBCT assessment.

This study investigates the effects of antiresorptive drugs and risk factors for medication-related osteonecrosis of the jaws in osteoporotic patients undergoing tooth extraction. Among the findings, antiresorptive-treated patients had thicker lamina dura and longer healing times. Additionally, corticosteroid intake and multi-rooted teeth carried a higher osteonecrosis risk. Bone sequestrum indicated osteonecrosis. PURPOSE: To describe the effects of antiresorptive drugs (ARD) in the maxilla and mandible and risk factors for medication-related osteonecrosis of the jaws (MRONJ) in osteoporotic patients undergoing tooth extractions using clinical data and cone beam computed tomography (CBCT). METHODS: This retrospective cohort study collected clinical and CBCT data from 176 patients. The study group (n = 78; 224 extractions) received ARD treatment, underwent tooth extraction, and had a pre-operative CBCT. Additionally, age-, sex-, and tooth-matched controls were selected (n = 98; 227 extractions). Radiographic examinations were performed independently by three calibrated examiners. Statistical analysis included Chi-square, Fisher's exact, Mann-Whitney U, and t-tests to contrast clinical and radiographic data between study and control, MRONJ + and MRONJ - , and bisphosphonate and denosumab patients/sites. Significance was set at p ≤ 0.05. RESULTS: From the study group, 4 patients (5%) and 5 sites (2%) developed MRONJ after tooth extraction. ARD-treated patients exhibited significantly more thickening of the lamina dura and a longer average mucosal healing time (4.4 weeks) than controls (2.6 weeks). In the study group, MRONJ risk significantly increased with corticosteroid intake and in multi-rooted teeth. No significant differences between bisphosphonates and denosumab use were seen in the tomographic features (p > 0.05). Lastly, bone sequestrum was exclusively observed in osteoporotic patients, who exhibited post-operative exposed bone or histological evidence of osteonecrosis. CONCLUSION: Osteoporotic patients under ARD may exhibit thickening of the lamina dura and prolonged post-operative healing. Among these patients, multi-rooted teeth are at higher risk for MRONJ than single-rooted teeth. Sequester formation is a radiographic indicator of osteonecrosis.

Osteoporosis management in adults with schizophrenia following index hip fracture event: a 10-year population-based retrospective cohort study, Ontario, Canada.

Little is known about the incidence of osteoporosis testing and treatment in individuals with schizophrenia, who may be more likely to fracture. Using competing risk models, we found that schizophrenia was associated with lower incidence of testing or treatment. Implications are for understanding barriers and solutions for this disadvantaged group. PURPOSE: Evidence suggests that individuals with schizophrenia may be more likely to experience hip fractures than the general population; however, little is known about osteoporosis management in this disadvantaged subpopulation. Our study objective was to compare bone mineral density (BMD) testing and pharmacologic treatment in hip fracture patients with versus without schizophrenia. METHODS: This was a retrospective population-based cohort study leveraging health administrative databases, and individuals aged 66-105 years with hip fracture between fiscal years 2009 and 2018 in Ontario, Canada. Schizophrenia was ascertained using a validated algorithm. The outcome was a composite measure of (1) pharmacologic prescription for osteoporosis; or (2) a BMD test. Inferential analyses were conducted using Fine-Gray subdistribution hazard regression, with mortality as the competing event. RESULTS: A total of 52,722 individuals aged 66 to 105 years who sustained an index hip fracture in Ontario during the study period were identified, of whom 1890 (3.6%) had schizophrenia. Hip fracture patients with vs without schizophrenia were more likely to be long-term care residents (44.3% vs. 18.1%; standardized difference, 0.59), frail (62.5% vs. 36.5%; standardized difference, 0.54) and without a primary care provider (9.2% vs. 4.8%; standardized difference, 0.18). In Fine-Gray models, schizophrenia was associated with a lower incidence of testing or treatment (0.795 (0.721, 0.877)). CONCLUSIONS: In this population-based retrospective cohort study, a schizophrenia diagnosis among hip fracture patients was associated with a lower incidence of testing or treatment, after accounting for mortality, and several enabling and predisposing factors. Further research is required to investigate barriers to osteoporosis management in this disadvantaged population.

Trabecular bone mineral density as measured by thoracic vertebrae predicts incident hip and vertebral fractures: the multi-ethnic study of atherosclerosis.

We evaluated the relationship of bone mineral density (BMD) by computed tomography (CT), to predict fractures in a multi-ethnic population. We demonstrated that vertebral and hip fractures were more likely in those patients with low BMD. This is one of the first studies to demonstrate that CT BMD derived from thoracic vertebrae can predict future hip and vertebral fractures. PURPOSE/INTRODUCTION: Osteoporosis affects an enormous number of patients, of all races and both sexes, and its prevalence increases as the population ages. Few studies have evaluated the association between the vertebral trabecular bone mineral density(vBMD) and osteoporosis-related hip fracture in a multiethnic population, and no studies have demonstrated the predictive value of vBMD for fractures. METHOD: We sought to determine the predictive value of QCT-based trabecular vBMD of thoracic vertebrae derived from coronary artery calcium scan for hip fractures in the Multi-Ethnic Study of Atherosclerosis(MESA), a nationwide multicenter cohort included 6814 people from six medical centers across the USA and assess if low bone density by QCT can predict future fractures. Measures were done using trabecular bone measures, adjusted for individual patients, from three consecutive thoracic vertebrae (BDI Inc, Manhattan Beach CA, USA) from non-contrast cardiac CT scans. RESULTS: Six thousand eight hundred fourteen MESA baseline participants were included with a mean age of 62.2 ± 10.2 years, and 52.8% were women. The mean thoracic BMD is 162.6 ± 46.8 mg/cm3 (95% CI 161.5, 163.7), and 27.6% of participants (n = 1883) had osteoporosis (T-score 2.5 or lower). Over a median follow-up of 17.4 years, Caucasians have a higher rate of vertebral fractures (6.9%), followed by Blacks (4.4%), Hispanics (3.7%), and Chinese (3.0%). Hip fracture patients had a lower baseline vBMD as measured by QCT than the non-hip fracture group by 13.6 mg/cm3 [P < 0.001]. The same pattern was seen in the vertebral fracture population, where the mean BMD was substantially lower 18.3 mg/cm3 [P < 0.001] than in the non-vertebral fracture population. Notably, the above substantial relationship was unaffected by age, gender, race, BMI, hypertension, current smoking, medication use, or activity. Patients with low trabecular BMD of thoracic vertebrae showed a 1.57-fold greater risk of first hip fracture (HR 1.57, 95% CI 1.38-1.95) and a nearly threefold increased risk of first vertebral fracture (HR 2.93, 95% CI 1.87-4.59) compared to normal BMD patients. CONCLUSION: There is significant correlation between thoracic trabecular BMD and the incidence of future hip and vertebral fracture. This study demonstrates that thoracic vertebrae BMD, as measured on cardiac CT (QCT), can predict both hip and vertebral fractures without additional radiation, scanning, or patient burden. Osteopenia and osteoporosis are markedly underdiagnosed. Finding occult disease affords the opportunity to treat the millions of people undergoing CT scans every year for other indications.

3D-DXA Based Finite Element Modelling for Femur Strength Prediction: Evaluation Against QCT.

Osteoporosis is characterised by the loss of bone density resulting in an increased risk of fragility fractures. The clinical gold standard for diagnosing osteoporosis is based on the areal bone mineral density (aBMD) used as a surrogate for bone strength, in combination with clinical risk factors. Finite element (FE) analyses based on quantitative computed tomography (QCT) have been shown to estimate bone strength better than aBMD. However, their application in the osteoporosis clinics is limited due to exposure of patients to increased X-rays radiation dose. Statistical modelling methods (3D-DXA) enabling the estimation of 3D femur shape and volumetric bone density from dual energy X-ray absorptiometry (DXA) scan have been shown to improve osteoporosis management. The current study used 3D-DXA based FE analyses to estimate femur strength from the routine clinical DXA scans and compared its results against 151 QCT based FE analyses, in a clinical cohort of 157 subjects. The linear regression between the femur strength predicted by QCT-FE and 3D-DXA-FE models correlated highly (coefficient of determination R2 = 0.86) with a root mean square error (RMSE) of 397 N. In conclusion, the current study presented a 3D-DXA-FE modelling tool providing accurate femur strength estimates noninvasively, compared to QCT-FE models.

The effectiveness of virtual reality exercise games on balance functions and fear of falling in women with osteoporosis.

To investigate and compare the effectiveness of Nintendo Wii games and home exercises on balance functions in patients with osteoporosis, an important disease adversely affecting balance functions. The patients included in the study were randomized into two groups the Wii exercise group (n = 30) and the home exercise group (n = 30). Wii exercise group performed balance exercises with a Nintendo Wii device and balance board three times a week for 12 weeks under the supervision of a physiotherapist in the hospital, and home exercise group was prescribed home exercises three days a week for 12 weeks. Balance functions were evaluated with the timed up-and-go-test and Berg Balance Scale, and the fall risk was evaluated with the Falls Efficacy Scale at the beginning and end of 12 weeks of treatment. Comparison of pre- and post-treatment timed up-and-go-test, Berg Balance Scale, and Falls Efficacy Scale results in both groups revealed statistically significant improvements (p = 0.001; p < 0.05). Furthermore, post-treatment test scores between the two groups demonstrated a significant enhancement in Wii exercise group regarding the Berg Balance Scale score (Mean ± SD 52.9 ± 3.63) (p = 0.001; p < 0.05). Within the osteoporotic population, balance functions serve as robust predictors of fall risk. Improvement in balance functions is crucial for the prevention of falls and subsequent osteoporotic fractures. In our study, we found that balance exercises performed with Wii games are effective in improving balance functions in patients with osteoporosis.

Relationship between muscle and subcutaneous adipose tissue size and density and proximal femur bone in elderly women with hip fracture.

BACKGROUND: Both osteoporosis and sarcopenia are associated with aging, increasing the likelihood of falls in older adults and consequently raising the risk of hip fractures (HF). AIMS: To explore the relationship between the size and density of muscle and subcutaneous adipose tissue (SAT) and the bone mineral density (BMD) of the proximal femur in elderly women with HF. METHODS: Quantitative computed tomography (QCT) was conducted on the hips of 661 female participants who experienced low-energy acute HFs to measure both areal BMD (aBMD) and volume BMD (vBMD). Measurements were taken for the cross-sectional area (CSA) and density of the muscle around the hip and adjacent SAT. Multivariable linear regression models were applied to assess the relationship between these parameters. RESULTS: Most increases in the density of the gluteus medius and minimus muscle (G.Med/MinM) were correlated with higher BMD in the femoral neck fracture (FNF) group with osteoporosis. In the FNF group, gluteus maximus muscle (G.MaxM) density was negatively associated with the BMD parameters of the proximal femur in individuals with osteoporosis, while they were positively associated with nonosteoporosis. In the intertrochanteric fracture (ITF) group without osteoporosis, both FN aBMD and FN vBMD showed significant correlations with G.Med/MinM density. DISCUSSION: In women with HFs, bone and muscle are closely related. CONCLUSIONS: In older women with HFs, density but not CSA of the G.Med/MinM were associated with BMD parameters of the proximal femur. Osteoporosis may influence the relationship between G.MaxM density and proximal femur BMD in elderly women with FNF.

How does Hashimoto's thyroiditis affect bone metabolism?

Bone marrow contains resident cellular components that are not only involved in bone maintenance but also regulate hematopoiesis and immune responses. The immune system and bone interact with each other, coined osteoimmunology. Hashimoto's thyroiditis (HT) is one of the most common chronic autoimmune diseases which is accompanied by lymphocytic infiltration. It shows elevating thyroid autoantibody levels at an early stage and progresses to thyroid dysfunction ultimately. Different effects exert on bone metabolism during different phases of HT. In this review, we summarized the mechanisms of the long-term effects of HT on bone and the relationship between thyroid autoimmunity and osteoimmunology. For patients with HT, the bone is affected not only by thyroid function and the value of TSH, but also by the setting of the autoimmune background. The autoimmune background implies a breakdown of the mechanisms that control self-reactive system, featuring abnormal immune activation and presence of autoantibodies. The etiology of thyroid autoimmunity and osteoimmunology is complex and involves a number of immune cells, cytokines and chemokines, which regulate the pathogenesis of HT and osteoporosis at the same time, and have potential to affect each other. In addition, vitamin D works as a potent immunomodulator to influence both thyroid immunity and osteoimmunology. We conclude that HT affects bone metabolism at least through endocrine and immune pathways.

Cxcl9l and Cxcr3.2 regulate recruitment of osteoclast progenitors to bone matrix in a medaka osteoporosis model.

Bone homeostasis requires continuous remodeling of bone matrix to maintain structural integrity. This involves extensive communication between bone-forming osteoblasts and bone-resorbing osteoclasts to orchestrate balanced progenitor cell recruitment and activation. Only a few mediators controlling progenitor activation are known to date and have been targeted for intervention of bone disorders such as osteoporosis. To identify druggable pathways, we generated a medaka (Oryzias latipes) osteoporosis model, where inducible expression of receptor-activator of nuclear factor kappa-Β ligand (Rankl) leads to ectopic formation of osteoclasts and excessive bone resorption, which can be assessed by live imaging. Here we show that upon Rankl induction, osteoblast progenitors up-regulate expression of the chemokine ligand Cxcl9l. Ectopic expression of Cxcl9l recruits mpeg1-positive macrophages to bone matrix and triggers their differentiation into osteoclasts. We also demonstrate that the chemokine receptor Cxcr3.2 is expressed in a distinct subset of macrophages in the aorta-gonad-mesonephros (AGM). Live imaging revealed that upon Rankl induction, Cxcr3.2-positive macrophages get activated, migrate to bone matrix, and differentiate into osteoclasts. Importantly, mutations in cxcr3.2 prevent macrophage recruitment and osteoclast differentiation. Furthermore, Cxcr3.2 inhibition by the chemical antagonists AMG487 and NBI-74330 also reduced osteoclast recruitment and protected bone integrity against osteoporotic insult. Our data identify a mechanism for progenitor recruitment to bone resorption sites and Cxcl9l and Cxcr3.2 as potential druggable regulators of bone homeostasis and osteoporosis.

Glucocorticoids Increase Fracture Risk and Fracture Prevalence Independently from Bone Mineral Density and Clinical Risk Factors: Results from the Gliwice Osteoporosis (GO) Study.

The aim of the study was to establish the influence of glucocorticoids (GC) on fracture risk, probability, and prevalence. A set of 1548 postmenopausal women were divided into study group - treated with GC (n=114, age 66.48±7.6 years) and controls (n=1434, age 66.46±6.83 years). Data on clinical risk factors for osteoporosis and fractures were collected. Hip bone densitometry was performed using a device Prodigy (GE, USA). Fracture probability was established by FRAX, and fracture risk by Garvan algorithm and POL-RISK. Fracture risk and fracture probability were significantly greater for GC-treated women in comparison to controls. In the study group, there were 24, 3, 24, and 6 fractures noted at spine, hip, forearm, and arm, respectively. The respective numbers of fractures reported in controls at those skeletal sites were: 186, 23, 240, and 25. The use of GCs increased significantly prevalence of all major, spine and arm fractures. Also the number of all fractures was affected by GC use. Following factors significantly increased fracture probability: age (OR 1.04 per each year; 95% CI: 1.03-1.06), GC use (OR 1.54; 95% CI: 1.03-2.31), falls (OR 2.09; 95% CI: 1.60-2.73), and FN T-score (OR 0.62 per each unit; 95% CI: 0.54-0.71). In conclusion, in patients treated with GCs the fracture risk, probability, and prevalence were increased. This effect was evident regardless of whether GC therapy is included in the algorithm as a risk factor (FRAX, POL-RISK) or not taken into consideration (Garvan nomogram).

Bone mineral density in pediatric heart transplanted patients: A retrospective single-center study at Skåne University Hospital in Lund 1988-2016.

BACKGROUND: Impaired bone mineral density (BMD) and osteoporosis are commonly found in patients who have undergone heart transplantation (HT), which increases the risk for bone fractures which is associated with increased morbidity and mortality in adults. However, the long-term evolution of BMD after HT in pediatric patients has not been thoroughly investigated. METHOD: Bone mineral density up to 10 years after HT was investigated in 30 patients who underwent HT at an age <20 years at Skåne University Hospital in Lund 1988-2016. RESULTS: The total observed time was 235 person-years. Before HT, 86% had low BMD for chronologic age in the lumbar spine. In lumbar spine, BMD was significantly lower than normal for chronological age before HT (p = .034), but recovered at the 4th year (p = .009). In whole body, BMD was normal at the 4th annual check-up (p = .030) and remained so throughout the follow-up period. The median T score in the lumbar spine and femoral neck 10 years after HT did not differ between the two groups based on age at HT (<20 years vs 20 years or older; p = .779 in the lumbar spine and p = .388 in the femoral neck). CONCLUSIONS: Patients who undergo HT at an age of <20 years have low BMD for chronological age already before HT, but BMD may recover completely within the first 4 years after HT. The results indicate no difference in BMD at 10 years after HT between pediatric and adult patients.

Plastin 3 in health and disease: a matter of balance.

For a long time, PLS3 (plastin 3, also known as T-plastin or fimbrin) has been considered a rather inconspicuous protein, involved in F-actin-binding and -bundling. However, in recent years, a plethora of discoveries have turned PLS3 into a highly interesting protein involved in many cellular processes, signaling pathways, and diseases. PLS3 is localized on the X-chromosome, but shows sex-specific, inter-individual and tissue-specific expression variability pointing towards skewed X-inactivation. PLS3 is expressed in all solid tissues but usually not in hematopoietic cells. When escaping X-inactivation, PLS3 triggers a plethora of different types of cancers. Elevated PLS3 levels are considered a prognostic biomarker for cancer and refractory response to therapies. When it is knocked out or mutated in humans and mice, it causes osteoporosis with bone fractures; it is the only protein involved in actin dynamics responsible for osteoporosis. Instead, when PLS3 is upregulated, it acts as a highly protective SMN-independent modifier in spinal muscular atrophy (SMA). Here, it seems to counteract reduced F-actin levels by restoring impaired endocytosis and disturbed calcium homeostasis caused by reduced SMN levels. In contrast, an upregulation of PLS3 on wild-type level might cause osteoarthritis. This emphasizes that the amount of PLS3 in our cells must be precisely balanced; both too much and too little can be detrimental. Actin-dynamics, regulated by PLS3 among others, are crucial in a lot of cellular processes including endocytosis, cell migration, axonal growth, neurotransmission, translation, and others. Also, PLS3 levels influence the infection with different bacteria, mycosis, and other pathogens.