A Novel MRI-Based Paravertebral Muscle Quality (PVMQ) Score for Evaluating Muscle Quality and Bone Quality: A Comparative Study with the VBQ Score.

Purpose: 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.

The efficacy of bisphosphonates for osteoporosis in young Cushing's disease patients with biochemical remission: a retrospective cohort study.

Background: Patients with Cushing's disease (CD) often experience slow recovery of bone mineral density (BMD), and the effectiveness of anti-osteoporosis drugs in young CD patients who have achieved biochemical remission after surgery is not well understood. Therefore, we aimed to explore whether bisphosphonates could help accelerate the recovery of osteoporosis in young CD patients with remission. Methods: We retrospectively enrolled 34 young patients with CD who achieved postoperative biochemical remission. All patients suffered from osteoporosis before surgery and were divided into postoperative bisphosphonate treatment group (16 cases) and without bisphosphonate treatment group (18 cases). Clinical data, BMD (Z Value), and bone turnover markers were collected at the time of diagnosis and one year after successful tumor resection. Results: The Z values in the lumbar spine showed slight improvement in both groups at follow-up compared to baseline, but this improvement was not statistically significant. There was no significant difference observed between the two groups at follow-up. One year after operation, bone formation markers (OC and P1NP) were significantly higher than those at baseline in both groups. However, OC and P1NP in the bisphosphonate treatment group were lower than those in control group at one year follow-up. In without bisphosphonate treatment group, ß-CTX from follow-up visit was higher than that at baseline, while no significant difference was observed in the bisphosphonate treatment group before and after surgery. Conclusion: Young patients with Cushing's disease combined with osteoporosis might not benefit from bisphosphonate therapy for osteoporosis recovery in the first year after achieving biochemical remission.

Association of geriatric nutritional risk index with bone mineral density and osteoporosis in postmenopausal elderly women with T2DM.

BACKGROUND AND OBJECTIVES: To investigate the relationship between geriatric nutritional risk index (GNRI) and osteoporosis (OP) in postmenopausal elderly women with type 2 diabetes mellitus (T2DM). METHODS AND STUDY DESIGN: A total of 141 postmenopausal elderly women with T2DM was divided into OP and normal bone mineral density (BMD) groups, the differences in GRNI levels between the two groups were compared. According to the tertile levels of GRNI, T2DM were divided into three groups (T1, T2, T3 groups), and the differences in OP prevalence and levels of BMD among the three groups were compared. RESULTS: Among postmenopausal elderly women with T2DM, GNRI levels were lower in the OP group compared to the nor-mal BMD group [(103±5.46) vs. (105±5.46), p<0.05)]. With elevated GNRI levels, the BMD levels of femoral, total hip, total body, and lumbar vertebrae (L) were gradually increased, which were higher in the T3 group than in the T1 group (all p< 0.05). GNRI levels were positively correlated with the BMD levels of femoral, spine, total hip, total body, L1, L2, L3, L4, and L1-L4. GNRI was an independent influencing factor for the occurrence of OP (OR=0.887, 95%CI [0.795,0.988]). The ROC curve showed that the GNRI combined with serum ALP and P levels had a high predictive value for OP, with an area under the curve of 0.725 (p<0.01). CONCLUSIONS: In postmenopausal elderly women with T2DM, GNRI was independently and positively correlated with BMD levels. GNRI may be a predictor development of OP.

Multi-objective optimization of custom implant abutment design for enhanced bone remodeling in single-crown implants using 3D finite element analysis.

The optimal configuration of a customized implant abutment is crucial for bone remodeling and is influenced by various design parameters. This study introduces an optimization process for designing two-piece zirconia dental implant abutments. The aim is to enhance bone remodeling, increase bone density in the peri-implant region, and reduce the risk of late implant failure. A 12-month bone remodeling algorithm subroutine in finite element analysis to optimize three parameters: implant placement depth, abutment taper degree, and gingival height of the titanium base abutment. The response surface analysis shows that implant placement depth and gingival height significantly impact bone density and uniformity. The taper degree has a smaller effect on bone remodeling. The optimization identified optimal values of 1.5 mm for depth, 35° for taper, and 0.5 mm for gingival height. The optimum model significantly increased cortical bone density from 1.2 to 1.937 g/cm3 in 2 months, while the original model reached 1.91 g/cm3 in 11 months. The standard deviation of density showed more uniform bone apposition, with the optimum model showing values 2 to 6 times lower than the original over 12 months. The cancellous bone showed a similar trend. In conclusion, the depth and taper have a significant effect on bone remodeling. This optimized model significantly improves bone density uniformity.

Potential association of rheumatic diseases with bone mineral density and fractures: a bi-directional mendelian randomization study.

BACKGROUND: Previous studies have implicated rheumatoid arthritis as an independent risk factor for bone density loss. However, whether there is a causal relationship between rheumatic diseases and bone mineral density (BMD) and fractures is still controversial. We employed a bidirectional Mendelian analysis to explore the causal relationship between rheumatic diseases and BMD or fractures. METHODS: The rheumatic diseases instrumental variables (IVs) were obtained from a large Genome-wide association study (GWAS) meta-analysis dataset of European descent. Analyses were performed for the three rheumatic diseases: ankylosing spondylitis (AS) (n = 22,647 cases, 99,962 single nucleotide polymorphisms [SNPs]), rheumatoid arthritis (RA) (n = 58,284 cases, 13,108,512 SNPs), and systemic lupus erythematosus (SLE) (n = 14,267 cases, 7,071,163 SNPs). Two-sample Mendelian randomization (MR) analyses were carried out by using R language TwoSampleMR version 0.5.7. The inverse-variance weighted (IVW), MR-Egger, and weighted median methods were used to analyze the causal relationship between rheumatic diseases and BMD or fracture. RESULTS: The MR results revealed that there was absence of evidence for causal effect of AS on BMD or fracture. However, there is a positive causal relationship of RA with fracture of femur (95% CI = 1.0001 to 1.077, p = 0.046), and RA and fracture of forearm (95% CI = 1.015 to 1.064, p = 0.001). SLE had positive causal links for fracture of forearm (95% CI = 1.004 to 1.051, p = 0.020). Additionally, increasing in heel bone mineral density (Heel-BMD) and total bone mineral density (Total-BMD) can lead to a reduced risk of AS without heterogeneity or pleiotropic effects. The results were stable and reliable. There was absence of evidence for causal effect of fracture on RA (95% CI = 0.929 to 1.106, p = 0.759), and fracture on SLE (95% CI = 0.793 to 1.589, p = 0.516). CONCLUSIONS: RA and SLE are risk factors for fractures. On the other hand, BMD increasing can reduce risk of AS. Our results indicate that rheumatic diseases may lead to an increased risk of fractures, while increased BMD may lead to a reduced risk of rheumatic diseases. These findings provide insight into the risk of BMD and AS, identifying a potential predictor of AS risk as a reduction in BMD.

Causal relationship between bone mineral density and intervertebral disc degeneration: a univariate and multivariable mendelian randomization study.

BACKGROUND: Although previous studies have suggested a possible association between bone mineral density (BMD) and intervertebral disc degeneration (IDD), the causal relationship between them remains unclear. Evidence from accumulating studies indicates that they might mutually influence one another. However, observational studies may be affected by potential confounders. Meanwhile, Mendelian randomization (MR) study can overcome these confounders to assess causality. OBJECTIVES: This Mendelian randomization (MR) study aimed to explore the causal effect of bone mineral density (BMD) on intervertebral disc degeneration (IDD). METHODS: Summary data from genome-wide association studies of bone mineral density (BMD) and IDD (the FinnGen biobank) have been acquired. The inverse variance weighted (IVW) method was utilized as the primary MR analysis approach. Weighted median, MR-Egger regression, weighted mode, and simple mode were used as supplements. The Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) and MR-Egger regression were performed to assess horizontal pleiotropy. Cochran's Q test evaluated heterogeneity. Leave-one-out sensitivity analysis was further conducted to determine the reliability of the causal relationship. Multivariate MR (MVMR) analyses used multivariable inverse variance-weighted methods to individually and jointly adjust for four potential confounders, body mass index (BMI), Type2 diabetes, hyperthyroidism and smoking. A reverse MR analysis was conducted to assess potential reverse causation. RESULTS: In the univariate MR analysis, femoral neck bone mineral density (FNBMD), heel bone mineral density (eBMD), lumbar spine bone mineral density (LSBMD), and total body bone mineral density (TB BMD) had a direct causal effect on intervertebral disc degeneration (IDD) [FNBMD-related analysis: OR(95%CI) = 1.17 (1.04 to 1.31), p = 0.008, eBMD-related analysis: OR(95%CI) = 1.06 (1.01 to 1.12), p = 0.028, LSBMD-related analysis: OR(95%CI) = 1.20 (1.10 to 1.31), p = 3.38E-7,TB BMD-related analysis: OR(95%CI) = 1.20 (1.12 to 1.29), p = 1.0E-8]. In the MVMR analysis, it was revealed that, even after controlling for confounding factors, heel bone mineral density (eBMD), lumbar spine bone mineral density (LSBMD), and total body bone mineral density (TB BMD) still maintained an independent and significant causal association with IDD(Adjusting for heel bone mineral density: beta = 0.073, OR95% CI = 1.08(1.02 to 1.14), P = 0.013; Adjusting for lumbar spine bone mineral density: beta = 0.11, OR(95%CI) = 1.12(1.02 to 1.23), P = 0.03; Adjusting for total body bone mineral density: beta = 0.139, OR95% CI = 1.15(1.06 to 1.24), P = 5.53E - 5). In the reverse analysis, no evidence was found to suggest that IDD has an impact on BMD. CONCLUSIONS: The findings from our univariate and multivariable Mendelian randomization analysis establish a substantial positive causal association between BMD and IDD, indicating that higher bone mineral density may be a significant risk factor for intervertebral disc degeneration. Notably, no causal effect of IDD on these four measures of bone mineral density was observed. Further research is required to elucidate the underlying mechanisms governing this causal relationship.

Effectiveness of desertliving cistanche in managing hyperlipidemic osteoporosis in ovariectomized rats through the PI3K/AKT signaling pathway.

BACKGROUND: To aim of this study is to assess the mechanism through which Desertliving Cistanche modulates the PI3K/AKT signaling pathway in the treatment of hyperlipidemic osteoporosis in ovariectomized rats. METHODS: We randomly assigned specific-pathogen-free (SPF) rats into five groups (n = 10 per group). The normal control group received a standard diet, while the model group, atorvastatin group, diethylstilbestrol group, and treatment group were fed a high-fat diet. Four weeks later, bilateral ovariectomies were conducted, followed by drug interventions. After six weeks of treatment, relevant indicators were compared and analyzed. RESULTS: Compared to the normal control group, rats in the model group exhibited blurred trabecular morphology, disorganized osteocytes, significantly elevated levels of bone-specific alkaline phosphatase (BALP), bone Gla-protein (BGP), total cholesterol (TC), tumor necrosis factor-α (TNF-α), and receptor activator of NF-κB ligand (RANKL). Also, the model group revealed significantly reduced levels of ultimate load, fracture load, estradiol (E2), bone mineral density (BMD), osteoprotegerin (OPG), and phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt) in femoral tissue. The atorvastatin group presented with higher TC and TNF-α levels compared to the normal control group. Conversely, the treatment group demonstrated enhanced trabecular morphology, denser structure, smaller bone marrow cavities, and reduced BALP, BGP, TC, TNF-α, and RANKL levels. Furthermore, the treatment group exhibited higher levels of E2, BMD, OPG, and PI3K and Akt in bone tissue compared to the model group. The treatment group also had lower TC and TNF-α levels than the atorvastatin group. Biomechanical analysis indicated that after administration of Desertliving Cistanche, the treatment group had reduced body mass, increased ultimate and fracture load of the femur, denser bone structure, smaller bone marrow cavities, and altered periosteal arrangement compared to the model group. CONCLUSION: Our study revealed that Desertliving Cistanche demonstrated significant efficacy in preventing and treating postmenopausal hyperlipidemic osteoporosis in rats.

Differences in intestinal and renal Ca and P uptake in three different breeds of growing-finishing pigs.

This study investigated the differences in bone growth and turnover and calcium (Ca) and phosphorus (P) uptake among three different breeds of growing-finishing pigs. Ninety healthy Duroc, Xiangcun black (XCB), and Taoyuan black (TYB) pigs (30 pigs per breed) at 35 day-old (D) with the average body weight (BW) of their respective breed were assigned and raised to 185 D. The results showed that Duroc pigs had higher bone weight and length than the XCB and TYB pigs at 80, 125, and 185 D and the bone index at 185 D (p < 0.05). Duroc pigs had higher bone mineral densities (femur and tibia) compared with the other two breeds at 80 D and 125 D, whereas TYB pigs had higher mineral content and bone breaking load (rib) compared with the other two breeds at 185 D (p < 0.05). The bone morphogenetic protein-2 and osteocalcin concentrations were higher, and TRACP5b concentration was lower in serum of TYB pigs at 125 D (p < 0.05). Meanwhile, 1,25-dihydroxyvitamin D3, parathyroid hormone, thyroxine, and fibroblast growth factor 23 concentrations were higher in serum of TYB pigs at 185 D (p < 0.05). The TYB pigs had higher apparent total tract digestibility of P at 80 D and 185 D and bone Ca and P contents at 185 D in comparison to the Duroc pigs (p < 0.05). Furthermore, gene expressions related to renal uptake of Ca and P differed among the three breeds of pigs. Collectively, Duroc pigs have higher bone growth, whereas TYB pigs have a higher potential for mineral deposition caused by more active Ca uptake.

Correlation Between Implant Stability Quotient and Percussion Sound Frequency.

OBJECTIVES: To determine the correlation between the primary implant stability quotient and the implant percussion sound frequency. MATERIALS AND METHODS: A total of 14 pigs' ribs were scanned using a dental cone beam computed tomography (CBCT) scanner to classify the bone specimens into three distinct bone density Hounsfield units (HU) value categories: D1 bone: >1250 HU; D2: 850-1250 HU; D3: <850 HU. Then, 96 implants were inserted: 32 implants in D1 bone, 32 implants in D2 bone, and 32 implants in D3 bone. The primary implant stability quotient (ISQ) was analyzed, and percussion sound was recorded using a wireless microphone connected and analyzed with frequency analysis software. RESULTS: Statistically significant positive correlations were found between the primary ISQ and the bone density HU value (r = 0.719; p < 0.001), and statistically significant positive correlations between the primary ISQ and the percussion sound frequency (r = 0.606; p < 0.001). Furthermore, significant differences in primary ISQ values and percussion sound frequency were found between D1 and D2 bone, as well as between D1 and D3 bone. However, no significant differences were found in primary ISQ values and percussion sound frequency between D2 and D3 bone. CONCLUSION: The primary ISQ value and the percussion sound frequency are positively correlated.

Prevalence and risk factors predisposing low bone mineral density in patients with thalassemia.

Background: A common complication of thalassemia is secondary osteoporosis. This study aimed to assess the prevalence and factors associated with low BMD in thalassemic patients. Method: This is a cross-sectional study. Eligible patients were males aged within 18-49 years or premenopausal women diagnosed with thalassemia in Chiang Mai University Hospital between July 2021 and July 2022. The diagnosis of low BMD by dual-energy x-ray absorptiometry (DXA) was defined as a Z-score of -2.0 SD or lower in either the lumbar spine or femoral neck. Clinical factors associated with low BMD were analyzed using a logistic regression model. Results: Prevalence of low BMD was 62.4% from 210 patients with a mean age of 29.7 ± 7.6 years. The predominant clinical characteristics of low BMD thalassemia patients were being female, transfusion-dependent (TDT) and a history of splenectomy. From multivariable analysis, the independent variables associated with low BMD were transfusion dependency (odds ratio, OR 2.36; 95%CI 1.28 to 4.38; p=0.006) and body mass index (BMI) (OR 0.71; 95%CI 0.61 to 0.82; p<0.001). Among patients with low BMD, we observed a correlation between a Z-score with low IGF-1 levels (ß=-0.42; 95% CI -0.83 to -0.01; p=0.040), serum phosphate levels (ß=0.40; 95% CI 0.07 to 0.73; p=0.016) and hypogonadism (ß=-0.48, 95% CI -0.91 to -0.04, p=0.031). Conclusion: This study found a prevalence of low BMD in 62.4% of subjects. Factors associated with low BMD were TDT and BMI. Within the low BMD subgroup, hypogonadism, serum phosphate and low serum IGF-1 levels were associated with a lower Z-score.

Osteoporotic Fractures: Diagnosis, Evaluation, and Significance From the International Working Group on DXA Best Practices.

Osteoporotic fractures, also known as fragility fractures, are reflective of compromised bone strength and are associated with significant morbidity and mortality. Such fractures may be clinically silent, and others may present clinically with pain and deformity at the time of the injury. Unfortunately, and even at the time of detection, most individuals sustaining fragility fractures are not identified as having underlying metabolic bone disease and are not evaluated or treated to reduce the incidence of future fractures. A multidisciplinary international working group with representation from international societies dedicated to advancing the care of patients with metabolic bone disease has developed best practice recommendations for the diagnosis and evaluation of individuals with fragility fractures. A comprehensive narrative review was conducted to identify key articles on fragility fractures and their impact on the incidence of further fractures, morbidity, and mortality. This document represents consensus among the supporting societies and harmonizes best practice recommendations consistent with advances in research. A fragility fracture in an adult is an important predictor of future fractures and requires further evaluation and treatment of the underlying osteoporosis. It is important to recognize that most fragility fractures occur in patients with bone mineral density T scores higher than -2.5, and these fractures confirm the presence of skeletal fragility even in the presence of a well-maintained bone mineral density. Fragility fractures require further evaluation with exclusion of contributing factors for osteoporosis and assessment of clinical risk factors for fracture followed by appropriate pharmacological intervention designed to reduce the risk of future fracture. Because most low-trauma vertebral fractures do not present with pain, dedicated vertebral imaging and review of past imaging is useful in identifying fractures in patients at high risk for vertebral fractures. Given the importance of fractures in confirming skeletal fragility and predicting future events, it is recommended that an established classification system be used for fracture identification and reporting.

Prevalence and associated factors of low bone mineral density in people living with HIV: a cross-sectional study.

This study examined low bone mineral density (BMD) prevalence and associated factors among Chinese people living with HIV (PLWH), uncovering a persistent high BMD risk in older individuals, even after adjusting for age and body mass index (BMI). Notably, lopinavir/ritonavir (LPV/r) therapy was linked to reduced BMD, highlighting the imperative need for regular BMD monitoring and interventions in older PLWH. PURPOSE: HIV infection and antiretroviral therapy (ART) have been shown to contribute to lower BMD, resulting in an increased susceptibility to osteopenia and osteoporosis. However, there is limited knowledge about the prevalence of reduced BMD and its associated factors among Chinese PLWH. In this cross-sectional study, we aimed to investigate the prevalence and factors associated with low BMD among PLWH in China. METHODS: We retrospectively enrolled PLWH and non-HIV volunteers who underwent dual-energy X-ray absorptiometry (DXA) scans to measure bone density. Demographic information, laboratory test results, ART regimens, and treatment duration were collected. Univariate and multiple regression analyses were performed to identify factors influencing abnormal bone mass in PLWH. RESULTS: A total of 829 individuals were included in this study, comprising the HIV group (n = 706) and the non-HIV group (n = 123). The prevalence of low BMD among all PLWH was found to be 13.88% (98 out of 706). However, among PLWH aged 50 years and above, the prevalence increased to 65.32% (81 out of 124). In contrast, control subjects in the same age group had a prevalence of 38.21% (47 out of 123). After adjusting for age and BMI, older PLWH still demonstrated a higher prevalence of low BMD compared to the non-HIV group (68.24% vs 34.94%, P < 0.001). Multivariate analysis revealed that older age was strongly associated with a higher risk of low BMD among PLWH, with an odds ratio (OR) of 6.28 for every 10-year increase in age in the ART-naïve population (95% confidence intervals [CIs], 3.12-12.65; P < 0.001) and OR of 4.83 in the ART-experienced population (3.20-7.29, P < 0.001). Within the ART-experienced group, current LPV/r treatment was associated with an increased risk of low BMD (OR = 3.55, 1.24-10.14, P < 0.05), along with lower BMI (OR = 0.84, 0.75-0.95, P < 0.05), and elevated alkaline phosphatase (OR = 1.02, 1.01-1.03, P < 0.01). CONCLUSION: The prevalence of low BMD is higher among PLWH aged 50 years and above compared to non-HIV individuals. The use of LPV/r for ART is associated with reduced BMD. These findings emphasize the importance of regular monitoring of BMD in older PLWH and the need for appropriate interventions to mitigate the risks of osteopenia and osteoporosis in this population.

Effects of differences in dose and frequency of teriparatide on bone structure in Proximal Femur. - Analysis by DXA-based 3D-modeling (3D-SHAPER Software) -TRIPLE-BONE study (The effects of TeRIParatide preparation on bone mineraL density increase and BONE structure).

Trends toward more favorable improvement of the cortical bone parameters by once-weekly (56.5 µg once a week) and twice-weekly teriparatide (28.2 µg twice a week), and that of the trabecular bone parameters by once-daily (1/D) teriparatide (20 µg/day once a day) were shown. PURPOSE: To examine the effects of differences in the amount of teriparatide (TPTD) per administration and its dosing frequency on the bone structure in the proximal femur by dual-energy X-ray absorptiometry (DXA)-based 3D-modeling (3D-SHAPER software). METHODS: This was a multicenter retrospective study. Patients aged 50 years or older with primary osteoporosis who continuously received once-/twice-weekly (1・2/W, n = 60) or 1/D TPTD (n = 14) administration for at least one year were included in the study. Measurement regions included the femoral neck (FN), trochanter (TR), femoral shaft (FS), and total proximal hip (TH). Concurrently, the bone mineral density (BMD) and Trabecular Bone Score (TBS) were measured. RESULTS: The cross-sectional area, cross-sectional moment of inertia, and section modulus in the FS were significantly improved in the 1・2/W TPTD group, as compared to the 1/D TPTD group. However, significant improvement of the cortical thickness and buckling ratio in the FN was observed in the 1/D TPTD group, as compared to the 1・2/W TPTD group. Trabecular BMD values in the FS and TH were significantly increased in the 1/D TPTD group, as compared to the 1・2/W TPTD group, while the cortical BMD values in the TR, FS, and TH were significantly increased in the 1・2/W TPTD group, as compared to the 1/D TPTD group. CONCLUSION: Trends toward more favorable improvement of the cortical bone by 1・2/W TPTD and that of the trabecular bones by 1/D TPTD were observed.

Improving the identification of bone-specific physical activity using wrist-worn accelerometry: A cross-sectional study in 11-12-year-old Australian children.

Physical activity (PA) during childhood and adolescence is important for the accrual of maximal peak bone mass. The precise dose that benefits bone remains unclear as methods commonly used to analyze PA data are unsuitable for measuring bone-relevant PA. Using improved accelerometry methods, this study identified the amount and intensity of PA most strongly associated with bone outcomes in 11-12-year-olds. Participants (n = 770; 382 boys) underwent tibial peripheral quantitative computed tomography to assess trabecular and cortical density, endosteal and periosteal circumference and polar stress-strain index. Seven-day wrist-worn raw acceleration data averaged over 1-s epochs was used to estimate time accumulated above incremental PA intensities (50 milli-gravitational unit (mg) increments from 200 to 3000 mg). Associations between time spent above each 50 mg increment and bone outcomes were assessed using multiple linear regression, adjusted for age, sex, height, weight, maturity, socioeconomic position, muscle cross-sectional area and PA below the intensity of interest. There was a gradual increase in mean R2 change across all bone-related outcomes as the intensity increased in 50 mg increments from >200 to >700 mg. All outcomes became significant at >700 mg (R2 change = 0.6%-1.3% and p = 0.001-0.02). Any further increases in intensity led to a reduction in mean R2 change and associations became non-significant for all outcomes >1500 mg. Using more appropriate accelerometry methods (1-s epochs; no a priori application of traditional cut-points) enabled us to identify that ∼10 min/day of PA >700 mg (equivalent to running ∼10 km/h) was positively associated with pQCT-derived measures of bone density, geometry and strength in 11-12-year-olds.

Correlation between bone mineral density and type 2 diabetes mellitus in elderly men and postmenopausal women.

The relationship between bone mineral density and type 2 diabetes is still controversial. The aim of this study is to investigate the relationship between type 2 diabetes mellitus (T2DM) and bone mineral density (BMD) in elderly men and postmenopausal women. The participants in this study included 692 postmenopausal women and older men aged ≥ 50 years, who were divided into the T2DM group and non-T2DM control group according to whether or not they had T2DM. The data of participants in the two groups were collected from the inpatient medical record system and physical examination center systems, respectively, of the Tertiary Class A Hospital. All data analysis is performed in SPSS Software. Compared with all T2DM group, the BMD and T scores of lumbar spines 1-4 (L1-L4), left femoral neck (LFN) and all left hip joints (LHJ) in the non-T2DM group were significantly lower than those in the T2DM group (P < 0.05), and the probability of major osteoporotic fracture in the next 10 years (PMOF) was significantly higher than that in T2DM group (P < 0.001). However, with the prolongation of the course of T2DM, the BMD significantly decreased, while fracture risk and the prevalence of osteoporosis significantly increased (P < 0.05). We also found that the BMD of L1-4, LFN and LHJ were negatively correlated with homeostatic model assessment-insulin resistance (HOMA-IR) (P = 0.028, P = 0.01 and P = 0.047, respectively). The results also showed that the BMD of LHJ was positively correlated with indirect bilirubin (IBIL) (P = 0.018). Although the BMD was lower in the non-T2DM group than in the T2DM group, the prolongation of the course of T2DM associated with the lower BMD. And the higher prevalence of osteoporosis and fracture risk significantly associated with the prolongation of the course of T2DM. In addition, BMD was significantly associated with insulin resistance (IR) and bilirubin levels in T2DM patients.Registration number: China Clinical Trials Registry: MR-51-23-051741; https://www.medicalresearch.org.cn/search/research/researchView?id=c0e5f868-eca9-4c68-af58-d73460c34028 .

Effect of Menstrual Cycle and Hormonal Contraception on Musculoskeletal Health and Performance: Protocol for a Prospective Cohort Design and Cross-Sectional Comparison.

BACKGROUND: Women of reproductive age experience cyclical variation in the female sex steroid hormones 17ß-estradiol and progesterone during the menstrual cycle that is attenuated by some hormonal contraceptives. Estrogens perform a primary function in sexual development and reproduction but have nonreproductive effects on bone, muscle, and sinew tissues (ie, ligaments and tendons), which may influence injury risk and physical performance. OBJECTIVE: The purpose of the study is to understand the effect of the menstrual cycle and hormonal contraceptive use on bone and calcium metabolism, and musculoskeletal health and performance. METHODS: A total of 5 cohorts of physically active women (aged 18-40 years) will be recruited to participate: eumenorrheic, nonhormonal contraceptive users (n=20); combined oral contraceptive pill (COCP) users (n=20); hormonal implant users (n=20); hormonal intrauterine system users (n=20); and hormonal injection users (n=20). Participants must have been using the COCP and implant for at least 1 year and the intrauterine system and injection for at least 2 years. First-void urine samples and fasted blood samples will be collected for biochemical analysis of calcium and bone metabolism, hormones, and metabolic markers. Knee extensor and flexor strength will be measured using an isometric dynamometer, and lower limb tendon and stiffness, tone, and elasticity will be measured using a Myoton device. Functional movement will be assessed using a single-leg drop to assess the frontal plane projection angle and the qualitative assessment of single leg loading. Bone density and macro- and microstructure will be measured using ultrasound, dual-energy x-ray absorptiometry, and high-resolution peripheral quantitative computed tomography. Skeletal material properties will be estimated from reference point indentation, performed on the flat surface of the medial tibia diaphysis. Body composition will be assessed by dual-energy x-ray absorptiometry. The differences in outcome measures between the hormonal contraceptive groups will be analyzed in a one-way between-group analysis of covariance. Within the eumenorrheic group, the influence of the menstrual cycle on outcome measures will be assessed using a linear mixed effects model. Within the COCP group, differences across 2 time points will be analyzed using the paired-samples 2-tailed t test. RESULTS: The research was funded in January 2020, and data collection started in January 2022, with a projected data collection completion date of August 2024. The number of participants who have consented at the point of manuscript submission is 66. It is expected that all data analysis will be completed and results published by the end of 2024. CONCLUSIONS: Understanding the effects of the menstrual cycle and hormonal contraception on musculoskeletal health and performance will inform contraceptive choices for physically active women to manage injury risk. TRIAL REGISTRATION: ClinicalTrials.gov NCT05587920; https://classic.clinicaltrials.gov/ct2/show/NCT05587920. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/50542.

Gonadotropic Axis, Bone Mass, and Sarcopenia Assessment After Autologous Hematopoietic Stem Cell Transplantation for Lymphoma.

Gonadal dysfunction, the most frequent endocrine complication in both sexes after autologous hematopoietic cell transplant (HCT) could increase bone loss and sarcopenia, a disease characterized by reduced muscle strength and mass. Sarcopenia is associated with worse survival, lower remission rates, and progression-free survival in patients with lymphoma after HCT. Low bone mass affected approximately 20% of the transplanted patients within 2 years and harms quality of life. This study was conducted in a single center and identified a strong relationship with patients transplanted more recently by LEC (lomustine, etoposide, and cyclophosphamide) conditioning regimen with sarcopenia. Peripheral neuropathy and bone mass changes were also associated with sarcopenia as well, suggesting a relationship with muscle strength loss.