Adult Bone Strength Research Articles

Reduced bone strength in adults with moderate or complex congenital heart disease

BackgroundWe aimed to study bone mineral density (BMD) and skeletal strength in the growing population of adults with moderate or complex congenital heart disease (CHD). MethodsPeripheral quantitative computed tomography (pQCT) was performed on the radius and tibia in 49 adults with moderate or complex CHD, and in 49 age and sex matched controls (n ​= ​23 [47%] female, mean age 36 ​± ​15.5 years.) Strength in the radius and tibia were presented, respectively, in terms of Strength-Strain Index (SSI). ResultsPatients had similar total BMD as controls in both the radius (807 ​± ​82 vs. 792 ​± ​75 ​mg/cm3, p ​= ​0.3) and tibia (663 ​± ​86 vs. 689 ​± ​67 ​mg/cm3, p ​= ​0.1). In the radius, patients had a lower xSSI than controls (154 ​± ​46 vs. 175 ​± ​54 ​mm3, p ​= ​0.04) but a similar ySSI (178 ​± ​58 vs. 195 ​± ​55 ​mm3, p ​= ​0.1). In the tibia, patients had a lower xSSI (1492 ​± ​399 vs. 1780 ​± ​372 ​mm3, p ​< ​0.001) as well as ySSI (1066 ​± ​304 vs. 1250 ​± ​281, p ​= ​0.002). In a multiple linear regression model, only height was independently associated with decreased skeletal strength in patients tibia in terms of xSSI [F(2,46) ​= ​40.002, p ​< ​0.001, R2 ​= ​0.635]. ConclusionAdults with moderate or complex CHD had reduced strength in the radius and tibia, despite a normal BMD as assessed with pQCT. Their reduced bone strength could increase the risk of future fractures.

Calcaneal Ultrasound and Its Relation to Dietary and Lifestyle Factors, Anthropometry, and Vitamin D Deficiency in Young Medical Students.

BackgroundBone quality and peak bone mass are greatly affected by lifestyle factors. The objective of the study was to investigate the relationships between anthropometry, dietary and caloric intake, body composition measurements, physical activity, and vitamin D status with quantitative ultrasound-based bone parameters among medical students.MethodsBoth male and female medical college students were included in this study. A detailed questionnaire was administered, collecting clinical, dietary, physical activity information, physical examination details, including body mass index (BMI). Body composition (total body fat, total body water, muscle mass, mean visceral fat mass, basal metabolic rate, bone mass using a bioelectrical impedance analyzer) and calcaneal heel ultrasound parameters were measured using an Osteosys Sonost-3000, Ultrasound Bone Densitometer were measured, respectively.ResultsIn this cross-sectional study, 211 healthy students with a mean age of 20.1 ± 1.1 years, 51.7% (n = 109) were males. Majority (79.4%) of the young adults had vitamin D deficiency. The mean BMI, calcium intake, and vitamin D levels were 22.35 ± 3.43 kg/m2, 788.7 ± 364.8 mg/day, and 15.02 ± 8.63 ng/ml, respectively. Female subjects compared to males had statistically significantly lower daily energy intake, muscle mass, visceral fat mass, calcium intake, and vitamin D levels. In addition the median Z-scores in females [−1.40 (−0.57 to −1.82)] was significantly poorer than the male [−0.50 (0.20 to −1.3)] counterparts, p-value <0.001. Multiple regression analysis showed that overall body fat percent (p-value 0.016) and visceral fat percent (p-value 0.029) were the only significant negative predictors to the calcaneal bone quality index (BQI) values.ConclusionAdolescent lifestyle patterns can influence young adult bone strength. The young Pakistani females exhibited significantly lower dietary intakes and more inadequate bone parameters compared to males. Our data suggest that total body and visceral fat percent are the predominant negatively associated determinant of bone strength for this cohort. Calcaneal ultrasound can be utilized for mass screening of young adults for identification of low BMD.

The Effects of Ivacaftor on Bone Density and Microarchitecture in Children and Adults with Cystic Fibrosis.

Cystic fibrosis (CF) transmembrane conductance (CFTR) dysfunction may play a role in CF-related bone disease (CFBD). Ivacaftor is a CFTR potentiator effective in improving pulmonary and nutritional outcomes in patients with the G551D-CFTR mutation. The effects of ivacaftor on bone health are unknown. To determine the impact of ivacaftor on bone density and microarchitecture in children and adults with CF. Prospective observational multiple cohort study. Outpatient clinical research center within a tertiary academic medical center. Three cohorts of age-, race-, and gender-matched subjects were enrolled: 26 subjects (15 adults and 11 children) with CF and the G551D-CFTR mutation who were planning to start or had started treatment with ivacaftor within 3 months (Ivacaftor cohort), 26 subjects with CF were not treated with ivacaftor (CF Control cohort), and 26 healthy volunteers. All treatments, including Ivacaftor, were managed by the subjects' pulmonologists. Bone microarchitecture by high-resolution peripheral quantitative computed tomography (HR-pQCT), areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry (DXA) and bone turnover markers at baseline, 1, and 2 years. Cortical volume, area, and porosity at the radius and tibia increased significantly in adults in the Ivacaftor cohort. No significant differences were observed in changes in aBMD, trabecular microarchitecture, or estimated bone strength in adults or in any outcome measures in children. Treatment with ivacaftor was associated with increases in cortical microarchitecture in adults with CF. Further studies are needed to understand the implications of these findings.

Dmp1Cre-directed knockdown of parathyroid hormone-related protein (PTHrP) in murine decidua is associated with a life-long increase in bone mass, width, and strength in male progeny.

Parathyroid hormone-related protein (PTHrP, gene name Pthlh) is a pleiotropic regulator of tissue homeostasis. In bone, Dmp1Cre-targeted PTHrP deletion in osteocytes causes osteopenia and impaired cortical strength. We report here that this outcome depends on parental genotype. In contrast to our previous report using mice bred from heterozygous (flox/wild type) Dmp1Cre.Pthlhf/w parents, adult (16-week-old and 26-week-old) flox/flox (f/f) Dmp1Cre.Pthlhf/f mice from homozygous parents (Dmp1Cre.Pthlhf/f(hom) ) have stronger bones, with 40% more trabecular bone mass and 30% greater femoral width than controls. This greater bone size was observed in Dmp1Cre.Pthlhf/f(hom) mice as early as 12 days of age, when greater bone width was also found in male and female Dmp1Cre.Pthlhf/f(hom) mice compared to controls, but not in gene-matched mice from heterozygous parents. This suggested a maternal influence on skeletal size prior to weaning. Although Dmp1Cre has previously been reported to cause gene recombination in mammary gland, milk PTHrP protein levels were normal. The wide-bone phenotype was also noted in utero: Dmp1Cre.Pthlhf/f(hom) embryonic femurs were more mineralized and wider than controls. Closer examination revealed that Dmp1Cre caused PTHrP recombination in placenta, and in the maternal-derived decidual layer that resides between the placenta and the uterus. Decidua from mothers of Dmp1Cre.Pthlhf/f(hom) mice also exhibited lower PTHrP levels by immunohistochemistry and were smaller than controls. We conclude that Dmp1Cre leads to gene recombination in decidua, and that decidual PTHrP might, through an influence on decidual cells, limit embryonic bone radial growth. This suggests a maternal-derived developmental origin of adult bone strength. © 2021 American Society for Bone and Mineral Research (ASBMR).

NEUROMUSCULAR FITNESS IN EARLY LIFE AND ITS IMPACT ON BONE HEALTH IN ADULTHOOD: A SYSTEMATIC REVIEW.

ABSTRACTObjective: To systematically review the literature to verify the relationship between neuromuscular fitness indicators in childhood/adolescence and bone strength variables in adulthood.Data sources: A systematic review was conducted in PUBMED, SCOPUS, SPORTDiscus, Web of Science, PsycINFO, LILACS, and SciELO, covering the entire period until March 2019.Data synthesis: The search identified 1149 studies. After duplicity analysis and eligibility criteria, four studies were reported. In one study, baseline was childhood and, in the others, adolescence. In childhood, when adjusting the model for age and body mass index, a statistically significant relation was found for girls: standing long jump with quantitative ultrasound index (β=0.11; p<0.05) and with speed of sound (β=0.14; p<0.01). However, when controlling muscular performance in adulthood, the relationship was no longer significant. In adolescence, coefficients ranged from 0.16 for neuromotor battery and bone mineral density (BMD) in the lumbar region to 0.38 for hanging leg lift test and BMD of arms. The explained variance varied between 2% (bent arm hang for BMD total) and 12% (hanging leg-lift for BMD arms), therefore, a higher performance in neuromuscular fitness in adolescence was associated with better bone strength in adulthood.Conclusions: In adults, bone strength variables showed significant correlation from low to moderate magnitude with neuromuscular fitness indicators in adolescence, but not in childhood, after controlling for adult performance in neuromuscular fitness. However, there is limited evidence to support the neuromuscular fitness in early life as a determinant of bone strength in adulthood.

Evaluation of Bone Architecture and Bone Strength in Adults With Hypophosphatasia (HPP)

Evaluation of Bone Architecture and Bone Strength in Adults With Hypophosphatasia (HPP)

The microbial metagenome and bone tissue composition in mice with microbiome-induced reductions in bone strength.

The genetic components of microbial species that inhabit the body are known collectively as the microbiome. Modifications to the microbiome have been implicated in disease processes throughout the body and have recently been shown to influence bone. Prior work has associated changes in the microbial taxonomy (phyla, class, species, etc.) in the gut with bone phenotypes but has provided limited information regarding mechanisms. With the goal of achieving a more mechanistic understanding of the effects of the microbiome on bone, we perform a metagenomic analysis of the gut microbiome that provides information on the functional capacity of the microbes (all microbial genes present) rather than only characterizing the microbial taxa. Male C57Bl/6 mice were subjected to disruption of the gut microbiota (ΔMicrobiome) using oral antibiotics (from 4 to 16 weeks of age) or remained untreated (n = 6-7/group). Disruption of the gut microbiome in this manner has been shown to lead to reductions in tissue mechanical properties and whole bone strength in adulthood with only minor changes in bone geometry and density. ΔMicrobiome led to modifications in the abundance of microbial genes responsible for the synthesis of the bacterial cell wall and capsule; bacterially synthesized carbohydrates; and bacterially synthesized vitamins (B and K) (p < 0.01). Follow up analysis focused on vitamin K, a factor that has previously been associated with bone health. The vitamin K content of the cecum, liver and kidneys was primarily microbe-derived forms of vitamin K (menaquinones) and was decreased by 32-66% in ∆Microbiome mice compared to untreated animals (p < 0.01). Bone mineral crystallinity determined using Raman spectroscopy was decreased in ∆Microbiome mice (p = 0.01). This study illustrates the use of metagenomic analysis to link the microbiome to bone phenotypes and provides preliminary findings implicating microbially synthesized vitamin-K as a regulator of bone matrix quality.

Middle School Recreational Sport Participation as a Determinant of Adult Muscle and Bone Strength

Physical activity during adolescence promotes the development of skeletal strength and muscle function. Musculoskeletal adaptations result from mechanical forces common in sporting activities. Recent studies have reported strong positive correlations between muscle power and bone strength (Janz, 2015, Yingling, 2017). PURPOSE: To determine if participation in middle school sports (self-report questionnaire) resulted in greater muscle and bone strength later in life. METHODS: 79 participants, 41 female and 38 male (age (yrs) 29.2 + 10.8, height (cm) 166.5 + 9.2, body fat (%) 24.6 + 9.3) performed a Relative Grip Strength (RGS) test using a hand grip dynamometer, 1 Repetition Maximum leg extension test (1RM), and a vertical jump test. Peak Power (PP) was calculated from jump height (Sayers, 1999). Peripheral Quantitative Computed Tomography (pQCT) was used to measure bone strength (polar Strength-Strain Index (SSIp)) in the cortical region of the tibia and radius. A questionnaire completed by participants stated “Did you participate in recreational sports during middle school (Grades 6-8)?” Welch’s t-test determined differences in the muscle function tests and bone strength measures based on middle-school sports participation. RESULTS: 55 individuals participated in recreational sports during middle school, 16 individuals did not. Those who participated in sports during middle school had an average relative PP of 55.41 W/kg, RGS of 6.46 N/kg, 1RM of 2.86 RW/BM, radial SSIp of 279.31 mm3, and tibial SSIp of 2036.13 mm3. Individuals that did not participate in recreational sports during middle school had an average PP of 49.12 W/kg, RGS of 5.58 N/kg, 1RM of 2.45RW/BM, radial SSI of 268.49 mm3, tibial SSI of 1957.50 mm3. Middle school sports participation resulted in significantly greater PP (p = 0.008), RGS (p = 0.010) and 1RM (p = 0.018) but no differences were found for bone strength in either the radius or tibia. CONCLUSIONS: Adolescence is a key time for bone and muscle strength adaptation. However, the results suggest that self report of middle school recreational sport involvement may not be an optimal way to predict muscle and bone strength in adulthood. . Evaluating past activity by survey has limitations with self-reported activity including the inability to determine the intensity of activity.

Contribution of High School Sport Participation to Young Adult Bone Strength

Nearly 8 million American adolescents participate in sports. Participation declines in young adulthood. This study assessed longitudinal effects of high school sport participation and muscle power on young adult bone strength. Two hundred twenty-eight young adults from the Iowa Bone Development Study completed an interscholastic sport participation questionnaire. Current physical activity (PA) behaviors were assessed via questionnaire. Dual x-ray absorptiometry assessed hip areal bone mineral density and was used with hip structure analysis to estimate femoral neck section modulus and hip cross-sectional area. Peripheral quantitative computed tomography provided strength-strain index and bone strength index at 38% and 4% midshaft tibial sites, respectively. Vertical jump estimated muscle power at 17 yr. Sex-specific multiple linear regression predicted young adult bone outcomes based on sport participation groups. Mediation analysis analyzed the effects of muscle power on relationships between sport participation and bone strength. At follow-up, males participating in any interscholastic sport had greater bone strength than males who did not participate in sport. The explained variability in bone outcomes was 2% to 16%. Females who participated in sports requiring muscle power had greater bone strength than females who did not participate in sports or females who participated in nonpower sports (explained variability was 4%-10%). Muscle power mediated 24.7% to 41% of the effect of sport participation on bone outcomes in males and 19.4% to 30% in females. Former male interscholastic sport participants and female interscholastic power sport participants have stronger bones than peers even when adjusting for current PA. Muscle power did not fully explain differences in all bone outcomes, suggesting that sport participation has additional bone health benefits.

The development of inter-strain variation in cortical and trabecular traits during growth of the mouse lumbar vertebral body.

Age-related changes in cortical and trabecular traits have been well studied; however, very little is known about how these bone tissues co-develop from day 1 of postnatal growth to establish functional structures by adulthood. In this study, we aimed to establish how cortical and trabecular tissues within the lumbar vertebral body change during growth for three inbred mouse strains that express wide variation in adult bone structure and function. Bone traits were quantified for lumbar vertebral bodies of female A/J, C57BL/6J (B6), and C3H/HeJ (C3H) inbred mouse strains from 1 to 105days of age (n = 6-10 mice/age/strain). Inter-strain differences in external bone size were observed as early as 1day of age. Reciprocal and rapid changes in the trabecular bone volume fraction and alignment in the direction of axial compression were observed by 7days of age. Importantly, the inter-strain difference in adult trabecular bone volume fraction was established by 7days of age. Early variation in external bone size and trabecular architecture was followed by progressive increases in cortical area between 28 and 105days of age, with the greatest increases in cortical area seen in the mouse strain with the lowest trabecular mass. Establishing the temporal changes in bone morphology for three inbred mouse strains revealed that genetic variation in adult trabecular traits were established early in postnatal development. Early variation in trabecular architecture preceded strain-specific increases in cortical area and changes in cortical thickness. This study established the sequence of how cortical and trabecular traits co-develop during growth, which is important for identifying critical early ages to further focus on intervention studies that optimize adult bone strength.

Re-evaluation of Pleistocene and Holocene long bone robusticity trends with regards to age-at-death estimates and size standardization procedures

Long-term trends in robusticity of lower limb bones in the genus Homo through the Pleistocene until the present have been proposed, which have been interpreted as a consequence of decreasing levels of mobility and activity patterns, changes in lifestyle, and environmental factors. There has also long been evidence that skeletal strength increases over an individual's lifespan. This increase is caused by continuous bone remodeling that optimizes the structure of a bone to resist mechanical loadings and creates a balance between endosteal resorption and subperiosteal apposition. However, none of the previous studies of temporal trends in robusticity has considered both processes and analyzed how individual age-related robusticity might influence higher-level temporal trends. This paper therefore explores temporal trends in robusticity of lower limb long bones within the genus Homo and considers how individual ages-at-death can confound published evolutionary trends, given the fact that some aspects of relative bone strength tend to increase over individual lifespans. Cross-sectional diaphyseal properties of the midshaft and proximal femur and midshaft tibia of Pleistocene and early Holocene individuals, together with data on age-at-death are used to analyze changes in relative bone strength relative to individuals' ages and evolutionary time. The results show increasing bone strength in adulthood until the fourth decade and then a slight decrease, an observation that conforms to previously published results on recent human populations. However, no significant impact of age-at-death on the trends along an evolutionary trajectory has been detected. The evolutionary trends in femoral and tibial relative strength can be described as fluctuating, probably as a consequence of changing mobility patterns, environmentally and technologically influenced behaviors, and demographic processes. The differences between evolutionary trends published in several studies are explained primarily as a result of different ways of standardizing cross-sectional parameters for size, and differences in sample composition.

Early Trabecular Development in Human Vertebrae: Overproduction, Constructive Regression, and Refinement.

Early bone development may have a significant impact upon bone health in adulthood. Bone mineral density (BMD) and bone mass are important determinants of adult bone strength. However, several studies have shown that BMD and bone mass decrease after birth. If early development is important for strength, why does this reduction occur? To investigate this, more data characterizing gestational, infant, and childhood bone development are needed in order to compare with adults. The aim of this study is to document early vertebral trabecular bone development, a key fragility fracture site, and infer whether this period is important for adult bone mass and structure. A series of 120 vertebrae aged between 6 months gestation and 2.5 years were visualized using microcomputed tomography. Spherical volumes of interest were defined, thresholded, and measured using 3D bone analysis software (BoneJ, Quant3D). The findings showed that gestation was characterized by increasing bone volume fraction whilst infancy was defined by significant bone loss (≈2/3rds) and the appearance of a highly anisotropic trabecular structure with a predominantly inferior–superior direction. Childhood development progressed via selective thickening of some trabeculae and the loss of others; maintaining bone volume whilst creating a more anisotropic structure. Overall, the pattern of vertebral development is one of gestational overproduction followed by infant “sculpting” of bone tissue during the first year of life (perhaps in order to regulate mineral homeostasis or to adapt to loading environment) and then subsequent refinement during early childhood. Comparison of early bone developmental data in this study with adult bone volume values taken from the literature shows that the loss in bone mass that occurs during the first year of life is never fully recovered. Early development could therefore be important for developing bone strength, but through structural changes in trabecular microarchitecture rather than bone mass.

Adult bone strength of children from single-parent families: the Midlife in the United States Study.

Bone health may be negatively impacted by childhood socio-environmental circumstances. We examined the independent associations of single-parent childhood and parental death or divorce in childhood with adult bone strength indices. Longer exposure to a single-parent household in childhood was associated with lower bone strength in adulthood. Because peak bone mass is acquired during childhood, bone health may be negatively impacted by childhood socio-environmental disadvantage. The goal of this study was to determine whether being raised in a single-parent household is associated with lower bone strength in adulthood. Using dual-energy X-ray absorptiometry data from 708 participants (mean age 57 years) in the Midlife in the United States Biomarker Project, we examined the independent associations of composite indices of femoral neck bone strength relative to load (in three failure modes: compression, bending, and impact) in adulthood with the experience of single-parent childhood and parental death or divorce in childhood. After adjustment for gender, race, menopause transition stage, age, and body mass index, each additional year of single-parent childhood was associated with 0.02 to 0.03 SD lower indices of adult femoral neck strength. In those with 9-16 years of single-parent childhood, the compression strength index was 0.41 SD lower, bending strength index was 0.31 SD lower, and impact strength index was 0.25 SD lower (all p values < 0.05). In contrast, parental death or divorce during childhood was not by itself independently associated with adult bone strength indices. The magnitudes of these associations were unaltered by additional adjustment for lifestyle factors and socioeconomic status in childhood and adulthood. Independent of parental death or divorce, growing up in a single-parent household is associated with lower femoral neck bone strength in adulthood, and this association is not entirely explained by childhood or adult socioeconomic conditions or lifestyle choices.

Time since onset of walking predicts tibial bone strength in early childhood

Bone strength in adulthood is known to be affected by health at birth and early childhood. Habitual bone loading is a primary determinant of bone strength in later childhood and adulthood. However, the effects of physical activity in early childhood (e.g. crawling, standing and walking) on bone strength are unknown. Fifty-three children (twenty-seven males) were included in a longitudinal study in their early infancy. Shortly after birth (0.3±0.3months), details of mass and height were obtained along with a pQCT scan at 20% distal–proximal tibia length. At 14.8±0.5months of age the same data were collected, along with details of age at onset of standing, crawling, supported and unsupported walking. Time since onset of walking unsupported was associated with greater bone mass, cortical bone area, pericortical circumference and polar moment of inertia of both total and cortical bone (all P<0.05). There were no significant associations between other physical activity timepoints and bone measures. Age at onset of walking was not significantly related to mass, length or bone measures at birth. The results suggest that time since attainment of independent walking — representing exposure of the tibia to the large reaction and muscular forces associated with locomotion — is a primary determinant of bone strength in early childhood. This finding raises the possible opportunity of physical activity interventions at young age in paediatric populations associated with low childhood bone strength and late walking (e.g. low birth weight, cerebral palsy and Down's Syndrome, etc.).

Compromised trabecular microarchitecture and lower finite element estimates of radius and tibia bone strength in adults with turner syndrome: A cross-sectional study using high-resolution–pQCT

Although bone mass appear ample for bone size in Turner syndrome (TS), epidemiological studies have reported an increased risk of fracture in TS. We used high-resolution peripheral quantitative computed tomography (HR-pQCT) to measure standard morphological parameters of bone geometry and microarchitecture, as well as estimated bone strength by finite element analysis (FEA) to assess bone characteristics beyond bone mineral density (BMD) that possibly contribute to the increased risk of fracture. Thirty-two TS patients (median age 35, range 20-61 years) and 32 healthy control subjects (median age 36, range 19-58 years) matched with the TS participants with respect to age and body-mass index were studied. A full region of interest (ROI) image analysis and a height-matched ROI analysis adjusting for differences in body height between groups were performed. Mean bone cross-sectional area was lower in TS patients in radius (-15%) and tibia (-13%) (both p < 0.01) whereas cortical thickness was higher in TS patients in radius (18%, p < 0.01) but not in tibia compared to controls. Cortical porosity was lower in TS patients at both sites (-32% in radius, -36% in tibia, both p < 0.0001). Trabecular integrity was compromised in TS patients with lower bone volume per tissue volume (BV/TV) (-27% in radius, -22% in tibia, both p < 0.0001), trabecular number (-27% in radius, -12% in tibia, both p < 0.05), and higher trabecular spacing (54% in radius, 23% in tibia, both p < 0.01). In the height-matched ROI analysis, differences remained significant apart from total area at both sites, cortical thickness in radius, and trabecular number in tibia. FEA estimated failure load was lower in TS patients in both radius (-11%) and tibia (-16%) (both p < 0.01) and remained significantly lower in the height-matched ROI analysis. Conclusively, TS patients had compromised trabecular microarchitecture and lower bone strength at both skeletal sites, which may partly account for the increased risk of fracture observed in these patients.

Femoral neck geometry in overweight and normal weight adolescent girls

Being overweight is associated with increased bone mineral content, bone mineral density (BMD), and bone strength in adults. However, the effect of being overweight on bone strength during adolescence is poorly understood. The aim of this study was to compare femoral neck geometry in overweight and normal weight adolescent girls. This study included 22 overweight (BMI > 25 kg/m(2)) adolescent girls (15.4 +/- 2.4 years old) and 20 maturation-matched (15.2 +/- 1.9 years old) controls (BMI < 25 kg/m(2)). Body composition and BMD were assessed by dual-energy X-ray absorptiometry (DXA). To evaluate bone geometry, DXA scans were analyzed at the femoral neck by the hip structure analysis (HSA) program. Cross-sectional area (CSA), an index of axial compression strength, section modulus (Z), an index of bending strength, cross-sectional moment of inertia (CSMI), cortical thickness (CT), and buckling ratio (BR) were measured from bone mass profiles. Lean mass, body weight, fat mass, and BMI were higher in overweight girls compared to controls (P < 0.001). CSA, Z, and CSMI were higher in overweight girls compared to controls (P < 0.05; P < 0.01 and P < 0.01, respectively). CT and BR were not significantly different between the two groups. After adjustment for body weight, lean mass, or fat mass, using a one-way analysis of covariance (ANCOVA), there were no differences between the two groups (overweight and controls) regarding the HSA variables (CSA, Z, CSMI, CT, and BR). In conclusion, this study suggests that overweight adolescent girls have greater indices of bone axial and bending strength in comparison to controls at the femoral neck.

Birth weight predicts bone size in young adulthood at cortical sites in men and trabecular sites in women from The Gambia

Fracture risk is determined by bone mass, size and architecture. Birth weight (Bwt) is reported to predict adult bone mass and density. Early life environment may therefore be a determinant of bone strength in later life. However such evidence was obtained using dual energy X-ray absorptiometry (DXA), which is known to be dependent on size.We used peripheral quantitative computed tomography (pQCT) and DXA to investigate Bwt as a determinant of bone size and cross section area (CSA), bone mineral content (BMC) and volumetric bone mineral density (vBMD) and areal BMD (aBMD) independent of current weight, height and age. The study population consisted of 68 males and 52 nulliparous females aged 17 to 21years from Keneba, The Gambia. This population has a high prevalence of factors likely to influence skeletal development (poor nutrition, low calcium intake, late puberty and high physical activity).Measures of bone size and CSA, BMC and BMD were obtained using pQCT (Stratec 2000; at 4% and 66% radius; 4% and 50% tibia) and DXA (Lunar DPX; spine, hip, forearm and whole body). Sequential univariable (influence of Bwt on bone variables) and multivariable linear regression analyses (influence of Bwt on bone variables after adjusting for current height, weight and age) were used to investigate the independent effects of Bwt and attained size. Analyses were performed separately by sex.Bwt was a significant positive predictor of CSA at appendicular cortical sites in males and CSA and bone area at appendicular and most axial trabecular sites in females before and after adjustment for current height, weight and age. Bwt was not consistently related to BMC, vBMD or aBMD as measured by pQCT or DXA. Current weight was a positive predictor of aBMD and pQCT- and DXA-derived BMC in males and females. Height predicted aBMD and trabecular vBMD in males.In summary, Bwt significantly predicted attained CSA at cortical sites in males and at trabecular sites in females. Current weight was a positive predictor of BMC and aBMD in both sexes. This suggests that pre-natal factors affecting fetal growth may influence adult bone strength independently of post-natal factors.

Physiotherapie und Bewegung bei Osteoporose und Folgeerkrankungen

Osteoporosis is defined by decreased bone strength and increased susceptibility to fracture. Fractures and their consequences are the clinical manifestation of osteoporosis. Acute and chronic pain, functional limitations including permanent impairment and the need for long-term care may be caused by osteoporotic fractures. The aim of osteoporosis treatment is to prevent fractures by bone strengthening. The aims of rehabilitation in patients with osteoporosis are to reduce pain, maximize the level of musculoskeletal function, particularly following fractures, decrease risk of falls and optimize quality of life and independence. Certain sports and exercises greatly promote skeletal development in children and adolescents and augment bone strength in adults. Physiotherapy and therapeutic exercise may relieve pain, increase musculoskeletal function and form an important part of fall management.

Peripubertal estrogen levels and physical activity affect femur geometry in young adult women

The growing skeleton is particularly responsive to exercise around the time of puberty, suggesting a possible role for estrogen in mechanical adaptation in young women. We assessed femoral neck strength index at age 17 in young women with varying adolescent physical activity levels and E2 levels in the first 3 years after menarche. The results indicate that both E2 levels in the first year after menarche and adolescent physical activity are positively associated with bone strength in young adulthood, such that hormone levels may modify human osteogenic responses to exercise. It is well established that physical activity contributes to bone strength in young females, but less is known about how peripubertal estrogen affects skeletal responses to exercise. We used data from 84 participants in the Penn State Young Women's Health Study to test the prediction that young women who (1) had higher E2 levels during the first year after menarche or (2) were more physically active in adolescence will have greater bone strength at the end of adolescence. Subjects were divided into tertiles of physical activity and of E2 level in the first, second, and third postmenarchal years, and femoral strength was calculated from dual-energy X-ray absorptiometry scans of the proximal femur using hip structure analysis. At age 17, subjects with the highest E2 levels in year 1 after menarche had 5-14% greater strength in the narrow neck and intertrochanteric region, and the most active subjects had 10-11% greater strength in the femoral narrow neck vs. less active girls. This study suggests that both physical activity and peripubertal estrogen have important influences on young adult bone strength and that hormone levels may be mediators of human osteogenic responses to exercise.

Prediction of Dominant Skeletal Mass with Different Tests of Lower Limb Dominance

The site-specific effects of bone loading are evident when observing the effect of upper limb dominance on bone mass. For instance, studies of the upper extremity bones of tennis players have revealed greater bone mineral density (BMD) of the dominant arm. However, bone strength is commonly examined in the lower limbs, where the determination of lower limb dominance is not as straightforward as for the upper limbs. Clinicians and researchers often expressly scan the non-dominant limb. PURPOSE: To compare the ability of a selection of questionnaires and physical tests to predict lower limb dominance in terms of bone strength in adults. METHODS: We recruited 40 healthy men and women (20 M; 20 F) aged 18 to 30 years inclusive. Participants completed the Waterloo Footedness Questionnaire (WFQ) and answered a series of dominance-related questions. Several physical challenges were also performed, including a hop distance test, step recovery test, and tests for cerebral lateralization. Bilateral calcaneal broadband ultrasound attenuation (BUA) (QUS-2, Quidel, USA) and femoral neck (FN) BMD (XR-36, Norland, USA) were measured from all subjects. RESULTS: The WFQ, task-related side dominance questions and the step recovery test showed significant negative relationships for both FN and calcaneal mass (r = −0.35-−0.47, p < 0.03). The relationships between measures of dominance were high for some (e.g. step recovery test vs task-related side dominance questions and self-determined dominant foot vs WFQ; r = 0.64-0.75, p = 0.001), but non-significant for others (e.g. dominant hop distance test vs step recovery test and WFQ vs dominant hop distance). Regression analysis revealed that none of the tests could predict the strongest heel, whereas the step recovery test predicted 22% of the variance in determination of dominant FN BMD. Addition of task-related side dominance questions and the WFQ enhanced prediction to 44% of the variance in FN dominance determination. CONCLUSIONS: Self-determined functional side dominance is not a good predictor of skeletal strength dominance. In fact, analysis suggests that functional side dominance is inversely related to skeletal side dominance.