The Physical Activity Scale for the Elderly (PASE) is a validated test to assess physical activity in older people. It has not been investigated if physical activity, according to PASE, is associated with fracture risk independently from the clinical risk factors (CRFs) in FRAX, bone mineral density (BMD), comorbidity, and if such an association is due to differences in physical performance or bone parameters. The purpose of this study was to evaluate if PASE score is associated with bone characteristics, physical function, and independently predicts incident fracture in 3014 75-80-yr-old women from the population-based cross-sectional SUPERB study. At baseline, participants answered questionnaires and underwent physical function tests, detailed bone phenotyping with DXA, and high-resolution peripheral quantitative CT. Incident fractures were X-ray verified. Cox regression models were used to assess the association between PASE score and incident fractures, with adjustments for CRFs, femoral neck (FN) BMD, and Charlson comorbidity index. Women were divided into quartiles according to PASE score. Quartile differences in bone parameters (1.56% for cortical volumetric BMD and 4.08% for cortical area, Q4 vs Q1, p = .007 and p = .022, respectively) were smaller than quartile differences in physical performance (27% shorter timed up and go test, 52% longer one leg standing time, Q4 vs Q1). During 8 yr (median, range 0.20-9.9) of follow-up, 1077 women had any fracture, 806 a major osteoporotic fracture (MOF; spine, hip, forearm, humerus), and 236 a hip fracture. Women in Q4 vs. Q1 had 30% lower risk of any fracture, 32% lower risk of MOF, and 54% lower risk of hip fracture. These associations remained in fully adjusted models. In conclusion, high physical activity was associated with substantially better physical function and a lower risk of any fracture, MOF and hip fracture, independently of risk factors used in FRAX, FN BMD, and comorbidity.
The Physical Activity Scale for the Elderly (PASE) is a test to assess physical activity in older people. The purpose of this study was to evaluate if physical activity, according to PASE, is associated with bone parameters, physical function, and independently predicts future fracture in 3014 75–80-yr-old women from the population-based SUPERB study. At baseline, participants answered questionnaires, underwent physical function tests, and DXA. Subsequent fractures were X-ray verified. Women were divided into quartiles according to PASE score (Q1 least and Q4 most physically active). Women in Q4 had 27% shorter timed up and go test and 52% longer one leg standing time compared with Q1. During 8 yr of follow-up, 1077 women had any fracture, 806 a major osteoporotic fracture (MOF; spine, hip, forearm, humerus), and 236 a hip fracture. Women in Q4 vs. Q1 had 30% lower risk of any fracture, 32% lower risk of MOF, and 54% lower risk of hip fracture. These associations remained in models considering comorbidity, BMD, and clinical risk factors. In conclusion, high physical activity was independently associated with better physical function and a lower risk of any fracture.

To quantitatively investigate the age- and sex-related longitudinal changes in trabecular volumetric bone mineral density (vBMD) and vertebral body volume at the thoracolumbar spine in adults.
We retrospectively included 168 adults (mean age 58.7 ± 9.8 years, 51 women) who received ≥7 MDCT scans over a period of ≥6.5 years (mean follow-up 9.0 ± 2.1 years) for clinical reasons. Level-wise vBMD and vertebral body volume were extracted from 22720 thoracolumbar vertebrae using a convolutional neural network (CNN)-based framework with asynchronous calibration and correction of the contrast media phase. Human readers conducted semiquantitative assessment of fracture status and bony degenerations.
In the 40-60 years age group, women had a significantly higher trabecular vBMD than men at all thoracolumbar levels (p<0.05 to p<0.001). Conversely, men, on average, had larger vertebrae with lower vBMD. This sex difference in vBMD did not persist in the 60-80 years age group. While the lumbar (T12-L5) vBMD slopes in women only showed a non-significant trend of accelerated decline with age, vertebrae T1-11 displayed a distinct pattern, with women demonstrating a significantly accelerated decline compared to men (p<0.01 to p<0.0001). Between baseline and last follow-up examinations, the vertebral body volume slightly increased in women (T1-12: 1.1 ± 1.0 cm3; L1-5: 1.0 ± 1.4 cm3) and men (T1-12: 1.2 ± 1.3 cm3; L1-5: 1.5 ± 1.6 cm3). After excluding vertebrae with bony degenerations, the residual increase was only small in women (T1-12: 0.6 ± 0.6 cm3; L1-5: 0.7 ± 0.7 cm3) and men (T1-12: 0.7 ± 0.6 cm3; L1-5: 1.2 ± 0.8 cm3). In non-degenerated vertebrae, the mean change in volume was <5% of the respective vertebral body volumes.
Sex differences in thoracolumbar vBMD were apparent before menopause, and disappeared after menopause, likely attributable to an accelerated and more profound vBMD decline in women at the thoracic spine. In patients without advanced spine degeneration, the overall volumetric changes in the vertebral body appeared subtle.

Non-pharmacological therapies, such as whole-food interventions, are gaining interest as potential approaches to prevent and/or treat low bone mineral density (BMD) in postmenopausal women. Previously, prune consumption preserved two-dimensional BMD at the total hip. Here we demonstrate that prune consumption preserved three-dimensional BMD and estimated strength at the tibia.
OBJECTIVE: Dietary consumption of prunes has favorable impacts on areal bone mineral density (aBMD); however, more research is necessary to understand the influence on volumetric BMD (vBMD), bone geometry, and estimated bone strength.
METHODS: This investigation was a single center, parallel arm 12-month randomized controlled trial (RCT; NCT02822378) to evaluate the effects of 50 g and 100 g of prunes vs. a Control group on vBMD, bone geometry, and estimated strength of the radius and tibia via peripheral quantitative computed tomography (pQCT) in postmenopausal women. Women (age 62.1 ± 5.0yrs) were randomized into Control (n = 78), 50 g Prune (n = 79), or 100 g Prune (n = 78) groups. General linear mixed effects (LME) modeling was used to assess changes over time and percent change from baseline was compared between groups.
RESULTS: The most notable effects were observed at the 14% diaphyseal tibia in the Pooled (50 g + 100 g) Prune group, in which group × time interactions were observed for cortical vBMD (p = 0.012) and estimated bone strength (SSI; p = 0.024); all of which decreased in the Control vs. no change in the Pooled Prune group from baseline to 12 months/post.
CONCLUSIONS: Prune consumption for 12 months preserved cortical bone structure and estimated bone strength at the weight-bearing tibia in postmenopausal women.

Reconstructing three-dimensional (3D) models from two-dimensional (2D) images is necessary for preoperative planning and the customization of joint prostheses. However, the traditional statistical modeling reconstruction shows a low accuracy due to limited 3D characteristics and information loss. In this study, we proposed a new method to reconstruct the 3D models of femoral images by combining a statistical shape model with Laplacian surface deformation, which greatly improved the accuracy of the reconstruction. In this method, a Laplace operator was introduced to represent the 3D model derived from the statistical shape model. By coordinate transformations in the Laplacian system, novel skeletal features were established and the model was accurately aligned with its 2D image. Finally, 50 femoral models were utilized to verify the effectiveness of this method. The results indicated that the precision of the method was improved by 16.8%-25.9% compared with the traditional statistical shape model reconstruction. Therefore, the method we proposed allows a more accurate 3D bone reconstruction, which facilitates the development of personalized prosthesis design, precise positioning, and quick biomechanical analysis.
通过二维图像进行重建的三维模型，是目前术前规划、人工关节定制的普遍需求。本文提出一种统计形状模型与拉普拉斯曲面变形相结合的方法，应用于股骨图像的三维重建，以优化传统统计建模重建过程中特征不足和信息损失造成的精度问题。该方法将基于统计形状模型的重建结果用能够代表形状特征的拉普拉斯算子表示，在拉普拉斯坐标系下进行曲面结点坐标变换，建立骨骼新特征，使重建模型与二维图像充分拟合。最后选取50例股骨模型验证本方法的有效性。结果表明，引入拉普拉斯曲面变形后的方法较传统统计形状模型的精度提升了16.8%～25.9%。该方法能够以更高精度完成骨三维重建，为术前个性化假体设计及其精准定位与快速生物力学分析等研究提供模型基础。.

Age-related bone loss is to some extent unavoidable, but it may be decelerated with regular exercise continued into older age. Daily physical activity alongside structured exercise may be an important stimulus for maintaining bone strength, but the relationships of habitual physical activity with bone strength are sparsely investigated in older adults. Therefore, the main aim was to investigate if accelerometer-derived impact-based and intensity-minute-based measures of physical activity were associated with changes in femoral neck bone traits during a 12-month exercise intervention among community-dwelling older men and women. Data comes from the PASSWORD study (ISRCTN52388040), a year-long multicomponent exercise intervention. Participants were 299 older adults (mean age 74 ± 4 years, 58 % women), who self-reported not to meet the physical activity guidelines for older adults but did not have any contraindications for exercising. The multicomponent training program included both supervised and self-administered exercises aimed at improving muscle strength, postural balance, and aerobic endurance. Physical activity was assessed at baseline and at six months into the intervention, and femoral neck bone properties at baseline and at twelve months. Physical activity measures were accelerometer-measured mean daily osteogenic index score, low, medium, and high intensity impact counts, and sedentary, light, and moderate-to-vigorous intensity activity minutes. Femoral neck bone mineral density (BMD) was measured with DXA and structural strength indicators (cross-sectional area [CSA] and section modulus) were subsequently derived from hip structural analysis. Longitudinal associations of physical activity and bone outcomes were analyzed with generalized estimating equation linear models. Sex was included as a moderating factor, and models were further adjusted by potentially confounding factors (age, height, weight, smoking status, medications, chronic disease conditions, and strength training adherence). Participants increased their physical activity by all measures and decreased their sedentary time from baseline to six months. BMD decreased from baseline to post-intervention, while CSA maintained stable and section modulus slightly increased. Osteogenic index, high impacts, and moderate-to-vigorous intensity physical activity, measured across the first half of the study, were positively associated with changes in BMD over 12 months (time х physical activity interaction effect: ß = 0.065, 95 % CI [0.004, 0.126]; ß = 0.169, 95 % CI [0.048, 0.289]; and ß = 0.151, 95 % CI [0.016, 0.286], respectively). That is, the higher the physical activity was, the smaller was the decline in BMD. Any physical activity measure was not associated with changes in CSA or section modulus in the full study sample. Sex did not significantly moderate the longitudinal associations, except the association between sedentary time and CSA (sex х time х PA interaction effect: ß = -0.017, 95 % CI [-0.033, -0.002]). An inverse association was found between sedentary time and changes in CSA in women, but not in men. In conclusion, BMD decline was less pronounced in individuals who accumulated more accelerometer-measured daily physical activity at the intensity of very brisk walking or light lateral jumping or higher intensities in a sample of relatively healthy, previously physically inactive older adults. Our findings support that accumulating the recommended amount of 150 or more weekly minutes of moderate-to-vigorous physical activity is also beneficial for older adults\' bone health when incorporated into a multicomponent exercise program.

Our objective was to characterize bone outcomes in adolescent and young adult women with atypical anorexia nervosa (AAN) compared to typical AN and normal-weight healthy controls (HC) based on DSM-5 criteria. Four hundred thirty-two participants (141 AN, 131 AAN and 160 HC), ages 12-21 years, underwent dual-energy X-ray absorptiometry for areal BMD, and a subset had high-resolution peripheral quantitative CT assessment of the distal radius and tibia for volumetric BMD (vBMD), bone geometry and microarchitecture, and microfinite element analysis for estimated strength. The groups did not differ for age, pubertal stage, menarcheal age or physical activity. BMI and bone outcomes overall were intermediate in AAN compared with AN and HC. This applied to spine, total hip and femoral neck BMD measures and many distal tibial measures. However, the mean whole-body less head BMD Z-score did not differ between AAN and AN, and it was lower in both vs. HC. Similarly, many distal radius measures did not differ between AAN vs. AN or HC but were lower in AN than HC. Lower BMI, lean mass and bone age, older menarcheal age and longer illness duration correlated with greater impairment of bone outcomes. These data indicate that individuals with AAN overall have bone outcomes that are intermediate between AN and HC.

OBJECTIVE: To determine mechanisms contributing to impaired bone health in youth 24 months following sleeve gastrectomy (SG).
METHODS: Twenty-four-month longitudinal observational study.
METHODS: Participants included 23 youth undergoing SG and 30 non-surgical controls (NS) 13-25 years old with moderate-to-severe obesity. Subjects underwent fasting labs for bone turnover markers (N-terminal propeptide of type 1 procollagen, C-telopeptide (CTX)), sex hormones, sex hormone binding globulin (SHBG), and enteric peptides, DXA for areal bone mineral density (aBMD) and body composition, high-resolution peripheral quantitative CT for volumetric BMD (vBMD) at the distal radius and tibia, and microfinite element analysis for strength estimates.
RESULTS: Groups did not differ for mean age or BMI z-scores. Over 24 months, compared to NS, SG had greater reductions in BMI z-scores, and spine, hip, and femoral neck aBMD Z-scores (P ≤ .012), greater increases in serum CTX and SHBG (P ≤ .039), and greater decreases in estrone and ghrelin (P ≤ .021). Among females, estrone and free androgen index (FAI) decreased (P ≤ .022) in SG vs NS groups. After controlling for age and sex, decreases in BMI and lean mass were associated with decreases in total hip and femoral neck aBMD Z-scores, and decreases in radial total and trabecular vBMD and failure load, and tibial total and trabecular vBMD. Among females, after controlling for age, decreases in estrone were associated with decreases in spine aBMD Z-scores and radial total and trabecular vBMD, and decrease in FAI with decreases in radial failure load.
CONCLUSIONS: Reductions in BMI, lean mass, and sex steroids over 24 months post-SG are associated with bone loss and could be targeted for preventative or therapeutic interventions. Clinical trial registration number: The study is registered in ClinicalTrials.gov (NCT02557438).

A primary function of the skeleton is to resist the loads imparted by body weight. Genetic analyses have identified genomic regions that contribute to differences in skeletal load resistance between laboratory strains of mice, but these studies are usually restricted to 1 or 2 bones and leave open the question of how load resistance evolves in natural populations. To address these challenges, we examined the genetics of bone structure using the largest wild house mice on record, which live on Gough Island (GI). We measured structural traits connected to load resistance in the femur, tibia, scapula, humerus, radius, ulna, and mandible of GI mice, a smaller-bodied reference strain from the mainland, and 760 of their F2s. GI mice have bone geometries indicative of greater load resistance abilities but show no increase in bone mineral density compared to the mainland strain. Across traits and bones, we identified a total of 153 quantitative trait loci (QTL) that span all but one of the autosomes. The breadth of QTL detection ranges from a single bone to all 7 bones. Additive effects of QTL are modest. QTL for bone structure show limited overlap with QTL for bone length and width and QTL for body weight mapped in the same cross, suggesting a distinct genetic architecture for load resistance. Our findings provide a rare genetic portrait of the evolution of load resistance in a natural population with extreme body size.

BACKGROUND: The bone-specific physical activity questionnaire (BPAQ) provides a bone-relevant index of physical activity participation according to the mechanical loads experienced across the life span.
METHODS: We aimed to examine relationships between historical bone-relevant physical activity and pQCT-derived parameters of bone strength. We recruited 532 healthy volunteers (277 males, 255 females) across a broad age range (4-97 years). Peripheral quantitative computed tomography (XCT-3000, Stratec, Germany) was used to examine volumetric bone density, area, and strength indices of the non-dominant tibia and radius. Exercise loading history from birth was determined using the past BPAQ (pBPAQ) score. Pearson correlation analysis was used to examine relationships between pBPAQ scores and pQCT parameters.
RESULTS: Independent of sex, pBPAQ scores were associated with total density at the 38% and 66% tibial sites and the 66% radial site (r = 0.145-0.261, p ˂ 0.05), total area at the 38% tibial site and 4% and 66% radial sites (r = 0.129-0.156, p ˂ 0.05), and strength indices at all measured sites (r = 0.123-0.234, p < 0.05).
CONCLUSIONS: We conclude that, independent of sex, historical bone-relevant physical activity is associated with pQCT-derived indices of bone strength, indicating that pBPAQ captures the characteristics of bone loading history that are likely to be relevant adaptive stimuli. A larger sample is required to examine the influence of age on this relationship.

Despite higher bone mineral density (BMD), women with obesity are at an increased risk of fracture compared to normal-weight women. Optimal adolescent bone accrual is critical for normal peak bone mass acquisition and future bone health. Whereas several studies have examined the impact of low body weight on bone accrual in youth, data are lacking regarding the impact of obesity on bone accrual. We examined bone accrual over one year in young women with moderate to severe obesity (OB) (n = 21) versus normal-weight controls (NWC) (n = 50). Participants were 13-25 years old. We used dual-energy X-ray absorptiometry to assess areal BMD (aBMD) and high resolution peripheral quantitative computed tomography (distal radius and tibia) to assess volumetric BMD (vBMD), bone geometry, and microarchitecture. Analyses were controlled for age and race. The mean age was 18.7 ± 2.7 years. OB and NWC were similar for age, race, height, and physical activity. OB had a higher BMI (p < 0.0001) and younger menarchal age (p = 0.022) than NWC. Over one year, OB did not demonstrate the increase in total hip BMD observed in NWC (p = 0.03). Increases in percent cortical area and cortical thickness, and cortical and total vBMD at the radius were lower in OB than in NWC (p ≤ 0.037). Groups did not differ for tibial bone accrual. We demonstrate that longitudinal bone accrual is impaired at the total hip and radial cortex in young women with obesity, raising concerns regarding their future bone health.