Calcaneal Stiffness Research Articles

Effect of denosumab on inflammation and bone health in active Charcot foot: A phase II randomised controlled trial

AimsWe aimed to investigate the effect of denosumab on pedal bone health and clinical resolution in active Charcot foot (CN). MethodsThis multicentre open-label phase 2 randomised controlled trial recruited adults with diabetes mellitus and active CN within 3 months of onset. Participants were randomised to standard care alone, or with denosumab 60 mg subcutaneously. Denosumab was administered at baseline and again at 6 months, unless foot temperature had normalised (i.e. <2 °C compared to contralateral foot). Co-primary outcomes were change in calcaneal Stiffness Index and foot temperature normalisation over 18 months. ResultsTwelve participants per group were analysed; mean age 58 ± 11 years, 83 % male and 92 % had type 2 diabetes. Active CN duration was median 8 (IQR 7–12) weeks. Ninety-two percent were Eichenholtz stage 1 and 96 % involved the midfoot. After 1-month, median decline in Stiffness Index was less in the denosumab verses standard care group (0.5 [IQR −1.0 to 3.9] vs −2.8 [−8.5 to −1.0], p = 0.008). At 18-months, 92 % of the denosumab group attained foot temperature normalisation versus 67 % of the standard care group (p = 0.13). ConclusionsDenosumab ameliorated the early decline in calcaneal Stiffness Index associated with active CN. However, no difference in normalisation of foot temperature was observed.

Association between walking speed and calcaneus stiffness index in older adults.

The aim here is to examine the association between objectively measured usual walking speed (UWS) and bone status in community-dwelling older Chinese. This is a cross-sectional study of a population of 1528 adults (817 females, mean age 68.5 ± 5.3; 711 males, mean age 69.1 ± 5.2) aged 60-79, living in communities in Shanghai. Walking speed was assessed using a 4-m walk test at a usual-pace walking speed a walking speed at which the subject felt relaxed-and bone status measured by quantitative ultrasound (QUS). The health-related characteristics of participants include family background, physical activity level, chronic disease, smoking and alcohol consumption, frequency of falls, vitamin intake, and hormone therapy. Multiple linear regression is used to analyses any association between UWS and bone status, adjusting for confounding factors showing a significant association between faster UWS and a higher calcaneal stiffness index (SI) (p < 0.01). Comparing the lowest quartile of the data set with the highest at UWS, a high SI is achieved with 5.34 (95% CI = 3.22, 7.46) (p < 0.01), after adjusting for confounders. An increase of 1dm/s was associated with a 0.91 (95% CI = 0.53, 1.29) increase in SI. This relationship for most subgroups is consistent. Our findings suggest that UWS can be a sensitive indicator of calcaneal bone loss among an older population.

Comparison of quantitative ultrasonography and dual X-ray absorptiometry for bone status assessment in South African children living with HIV.

Children living with HIV (CLHIV) have decreased bone mineral content (BMC) and density (BMD), increasing risk for fracture and future osteoporosis. While DXA is the gold-standard for bone assessments, it lacks availability in resource-constrained settings (RCS). Quantitative ultrasound (QUS) offers an alternative owing to its portability, low cost, ease of handling, and lack of ionizing radiation. While QUS has detected reduced bone quality in CLHIV, the relationship between QUS and DXA in this population remains unexplored. At baseline and 12 months, BMC and BMD of the whole body, lumbar spine, and radius were measured by DXA in a longitudinal cohort of CLHIV in Johannesburg, South Africa. Calcaneal speed of sound (SOS) and broadband ultrasound attenuation (BUA) and radius SOS were obtained by QUS, and calcaneal stiffness index (SI) was calculated. Spearman correlations, with and without HIV stratification, were performed between QUS and DXA measurements at each visit and for absolute difference in measurements between visits. At baseline and 12-months, calcaneal BUA and SI displayed strong positive correlations with DXA, with only modest correlations between radial QUS and DXA at baseline. Longitudinal measures of QUS did not correlate with DXA. At both baseline and 12-months, individuals with DXA whole-body BMD z-score < -1 displayed significantly lower calcaneal BUA and SI. Cross-sectionally, calcaneal QUS correlates strongly with whole body DXA and may represent a viable diagnostic alternative in RCS. Longitudinally, the two methods do not correlate well, possibly reflecting that each method assesses distinct aspects of bone architecture.

Characteristics of healthy German children and adolescents across tertiles of calcaneal stiffness index

AimIdentifying risk factors for low bone stiffness index (SI) might be one crucial strategy for osteoporosis prevention. Purpose was to characterize healthy schoolchildren across tertiles of SI.Subject and methodsIn 248 girls (13.4 ± 1.9 years, BMI: 20.2 ± 4.8 kg/m2) and 231 boys (13.6 ± 1.7 years, BMI: 19.3 ± 3.3 kg/m2), the following parameters were assessed: calcaneal SI (quantitative ultrasound), body composition (bioelectrical impedance analysis), Bone Healthy Eating Index (BoneHEI; food frequency questionnaire), and physical activity level (PAL; activity questionnaire). Participants were classified according to age- and sex-specific SI tertiles (low, medium, and high). Between-group comparisons were achieved by Kruskal–Wallis-H-tests (α = 0.05).ResultsGirls with low SI had significantly lower body mass (49.2 ± 16.7 vs 54.8 ± 12.2 kg; p < 0.01), BMI (19.6 ± 5.4 vs 21.3 ± 3.9 kg/m2; p < 0.0001), fat-free mass (36.3 ± 8.3 vs 39.5 ± 6.0 kg; p < 0.01), and fat mass (23.7 ± 9.1 vs 26.8 ± 7.2%; p < 0.05) compared to those with high SI. In boys, significant differences between low and high SI were obtained for PAL (1.49 ± 0.12 vs 1.56 ± 0.14; p < 0.01). BoneHEI was not significantly different between tertiles in both sexes.ConclusionGirls with low body mass and boys with low PAL have a higher risk for low SI. Schoolchildren should strive for normal body mass and perform regular physical activity.

Endurance running prevents the age-related decline of calcaneal bone stiffness.

Previous investigations have found that endurance runners have higher bone mineral density and other bone quality variables in mechanically loaded bones. However, it is unknown if endurance running might counteract the decline in bone stiffness that occurs with age. The purpose of this study was to compare calcaneus bone stiffness of endurance runners of different ages to age-matched controls. In a descriptive cross-sectional study, 182 endurance-trained male runners and 116 healthy untrained male controls underwent an ultrasonographic assessment of the calcaneus bone in the right and left heels. Calcaneal bone stiffness was calculated from assessments of the broadband ultrasound attenuation and the speed of sound. The line of best fit for the association between age and calcaneus stiffness was different between marathoners and controls (Z = - 2.1, P = 0.02). A two-way ANCOVA (condition × age) with body mass, and body mass index as covariates, revealed that there were main effects of condition (F = 26.8, P < 0.01) and age (F = 4.2, P < 0.01) for calcaneus stiffness, with a significant interaction between these two factors (F = 2.8, P = 0.03). The post hoc analysis revealed that calcaneus stiffness was significantly higher in marathoners of 40-44years (121.5 ± 18.2 vs 101.1 ± 21.3 arbitrary units [A.U.], P = 0.01), 45-49years (121.5 ± 19.7 vs 104.3 ± 13.4 A.U., P = 0.04), and > 50years (111.2 ± 17.9 vs 92.4 ± 16.0 A.U., P < 0.01) than their untrained counterparts of the same age with no statistically significant differences in the remaining age groups. Endurance runners of > 40years had higher values of calcaneus stiffness than controls, providing evidence to support the potential effect of endurance running to reduce the age-related decline on calcaneus bone stiffness.

Association between self-reported walking speed and calcaneal stiffness index in postmenopausal Japanese women

BackgroundOsteoporosis and related fractures, a worldwide public health issue of growing concern, is characterized by compromised bone strength and an increased risk of fracture. Here we show an association between self-reported walking speed and bone mass among community-dwelling postmenopausal Japanese women aged 50 years and older.Design; cross-sectional studySetting and Participants; The survey population included 1008 postmenopausal women 50–92 years of age residing in rural communities.MethodsSelf-reported walking speed was ascertained by asking the participants: “Is your walking speed faster than others of the same age and sex?” to which participants responded “yes (faster)” or “no (moderate/slower).” Calcaneal stiffness index was measured.ResultsWomen with a faster self-reported walking speed were younger and had a lower BMI, higher stiffness index, and higher grip strength than women with a slower walking speed. Multiple linear regression analysis adjusted for age, BMI, grip strength, comorbidity, current smoking, and alcohol drinking status showed a significant association between faster self-reported walking speed and higher calcaneal stiffness index (p < 0.001).ConclusionsOur findings suggest that questionnaires of walking speed may be useful for predicting bone mass and that a fast self-reported walking may benefit bone health in postmenopausal women.

Impact of physical activity, anthropometric, body composition, and dietary factors on bone stiffness in German university students.

Bone density in the young-adult life is associated with risk for osteoporosis in later life. Next to genetic factors, lifestyle seems to play an important role for bone health. Aim of the study was to clarify the relationship between various lifestyle factors and bone parameters in university students. In 233 women and 52 men (age: 22.7±3.1 vs. 24.0±3.2 years; BMI: 22.2±2.9 vs. 24.2±3.1 kg∙m-2) the following parameters were assessed: calcaneal Stiffness Index ([SI]; quantitative ultrasound), body composition (bioelectrical impedance analysis), actual and past physical activity level ([PAL]; standardized questionnaire), and food/nutrient intake (3-day dietary record). Sex differences (Mann-Whitney-U-tests), relationships between SI and lifestyle factors (Spearman's rank correlation), and the influence of the factors on the variance of SI (multiple linear regression) were tested (α=0.05). 6.9% of the women and 5.8% of the men were classified as osteopenic (-2.5< T score <-1). Significant correlations between SI and BMI, absolute fat mass and fat-free mass, actual PAL, and physical activity during adolescence were found in women (r=0.18-0.24, all P<0.05), but not in men. Food/nutrient parameters did not significantly correlate with bone outcomes (P>0.05). In multiple regression analysis physical activity during adolescence, actual PAL, and BMI explained 8% of the variance of SI (P<0.0001): SI=32.2+3.5∙physical activity during adolescence [1: very low, 2: low, 3: medium, 4: high, 5: very high] +28.5∙PAL+0.8∙BMI [kg∙m-2]. Parameters of physical activity seem to be more important for bone health than nutrition factors. Therefore, high levels of physical activity during childhood, adolescence, and early-adult life are highly recommended to improve bone parameters.

Influence of badminton practice on calcaneal bone stiffness and plantar pressure

ABSTRACTObjectives: The aim of this study was to analyze the plantar pressures and bone stiffness of the calcaneus in badminton players compare to healthy participants, as well as to detect possible asymmetries and chronic adaptations derived from the prolonged practice of badminton.Methods: Twenty-two badminton players (35.2 ± 13.6 years, 169.4 ± 8.2 cm, 67.6 ± 13.7 kg) and 30 healthy controls (32.2 ± 12.8 years, 170.7 ± 9.5 cm, 66.25 ± 14.84 kg) volunteered to participate in this investigation. A Footwork® Pro pressure platform was used to study plantar pressures and an Achilles® bone scanner was used to record the bone stiffness of the calcaneus. The variables analyzed were plantar surface, percentage of force per area (forefoot and hindfoot), distance between the center of pressure and the projection of the center of mass in standing, and calcaneal bone stiffness.Results: The values of bone stiffness of the calcaneus were higher in badminton players than control group in the dominant lower limb (Badminton = 114.32 ± 18.97 U.A. vs. Control = 102.07 ± 16.36 U.A.; p = 0.019) and non-dominant lower limb (Badminton = 115.12 ± 21.95 U.A. vs Control = 101.37 ± 15.72 U.A.; p = 0.014). Badminton players showed asymmetric values in mean pressure (dominant = 35.41 ± 6.05 Kpa vs. non-dominant = 39.21 ± 6.54 Kpa; p = 0.011) and distance among center of pressure of each foot and center of mass (dominant = 11.28 ± 1.65 cm vs. non-dominant = 10.48 ± 1.63 cm; p = 0.025).Conclusions: The calcaneal stiffness of the badminton players was higher than control group, which places badminton in the category of osteogenic sports. The badminton players showed an asymmetric pattern during the static balance, which may be an indicative of asymmetries derived from the continued practice of badminton.

Effect of self-reported walking difficulty on bone mass and bone resorption marker in Japanese people aged 40years and over.

BackgroundThis study aimed to examine the association of walking difficulty with bone mass or bone turnover among community-dwelling Japanese people aged 40 years and older.MethodsWe studied 1097 community-dwelling Japanese people aged 40 years and older (379 men and 718 women) who were invited to participate in periodic health examinations in 2006–2009. Walking difficulty was defined as having difficulty walking 100 m on a level surface (self-administered questionnaire). Calcaneal stiffness index (bone mass) was measured by quantitative ultrasound. Spot urine samples were collected, and urinary N-terminal cross-linking telopeptide of type I collagen (NTx) was measured. Values were corrected for creatinine (Cre) concentration.ResultsThe prevalence of walking difficulty was significantly higher in women than in men (7.4 vs. 3.4 %, p = 0.011) and significantly increased with age in men (p for trend = 0.02) and women (p for trend <0.001). In univariate analysis, men and women with walking difficulty were older (p < 0.001) and had a lower stiffness index (p < 0.001), compared with those without walking difficulty. Among women, individuals with walking difficulty had significantly higher urinary NTx/Cre than those without walking difficulty (p < 0.001); however, this was not so among men (p = 0.39). Multiple regression analysis adjusted for age, weight, and menopausal status showed a significant association between walking difficulty and lower stiffness index in men (p = 0.004) and women (p = 0.005). In women, walking difficulty was significantly associated with higher NTx/Cre (p = 0.001), but not in men (p = 0.35).ConclusionsWalking difficulty may contribute to low bone mass in both sexes but might cause high bone turnover in women only.

A cross-sectional study to evaluate the association of hyperbilirubinaemia on markers of cardiovascular disease, neurocognitive function, bone mineral density and renal markers in HIV-1 infected subjects on protease inhibitors

Background: Ongoing inflammation in controlled HIV infection contributes to non-AIDS comorbidities. High bilirubin appears to exhibit an anti-inflammatory effect in vivo. We therefore examined whether increased bilirubin in persons with HIV was associated with differences in markers of inflammation and cardiovascular, bone, renal disease, and neurocognitive (NC) impairment.Methods: This cross-sectional study examined inflammatory markers in individuals with stable HIV infection treated with two nucleoside reverse transcriptase inhibitors and a boosted protease inhibitor. Individuals recruited were those with a normal bilirubin (NBR; 0–17 μmol/L) or high bilirubin (>2.5 × upper limit of normal). Demographic and anthropological data were recorded. Blood and urine samples were taken for analyses. Pulse wave velocity (PWV) measurement, carotid intimal thickness (CIT), and calcaneal stiffness (CSI) were measured. Males were asked to answer a questionnaire about sexual function; NC testing was performed using CogState.Results: 101 patients were screened, 78 enrolled (43 NBR and 35 HBR). Atazanavir use was significantly higher in HBR. Whilst a trend for lower CIT was seen in those with HBR, no significant differences were seen in PWV, bone markers, calculated cardiovascular risk (Framingham), or erectile dysfunction score. VCAM-1 levels were significantly lower in the HBR group. HBR was associated with lower LDL and triglyceride levels. NBR was associated with a calculated FRAX significantly lower than HBR although no associations were found after adjusting for tenofovir use. No difference in renal markers was observed. Component tests of NC testing revealed differences favouring HBR but overall composite scores were similar.Discussion: High bilirubin in the context of boosted PI therapy was found not to be associated with differences in with the markers examined in this study. Some trends were noted and, on the basis of these, a larger, clinical end point study is warranted.

Impact of physical activity, sedentary behaviour and muscle strength on bone stiffness in 2-10-year-old children-cross-sectional results from the IDEFICS study.

BackgroundPhysical activity (PA), weight-bearing exercises (WBE) and muscle strength contribute to skeletal development, while sedentary behaviour (SB) adversely affects bone health. Previous studies examined the isolated effect of PA, SB or muscle strength on bone health, which was usually assessed by x-ray methods, in children. Little is known about the combined effects of these factors on bone stiffness (SI) assessed by quantitative ultrasound. We investigated the joint association of PA, SB and muscle strength on SI in children.MethodsIn 1512 preschool (2- < 6 years) and 2953 school children (6–10 years), data on calcaneal SI as well as on accelerometer-based sedentary time (SED), light (LPA), moderate (MPA) and vigorous PA (VPA) were available. Parents reported sports (WBE versus no WBE), leisure time PA and screen time of their children. Jumping distance and handgrip strength served as indicators for muscle strength. The association of PA, SB and muscle strength with SI was estimated by multivariate linear regression, stratified by age group. Models were adjusted for age, sex, country, fat-free mass, daylight duration, consumption of dairy products and PA, or respectively SB.ResultsMean SI was similar in preschool (79.5 ± 15.0) and school children (81.3 ± 12.1). In both age groups, an additional 10 min/day in MPA or VPA increased the SI on average by 1 or 2 %, respectively (p ≤ .05). The negative association of SED with SI decreased after controlling for MVPA. LPA was not associated with SI. Furthermore, participation in WBE led to a 3 and 2 % higher SI in preschool (p = 0.003) and school children (p < .001), respectively. Although muscle strength significantly contributed to SI, it did not affect the associations of PA with SI. In contrast to objectively assessed PA, reported leisure time PA and screen time showed no remarkable association with SI.ConclusionThis study suggests that already an additional 10 min/day of MPA or VPA or the participation in WBE may result in a relevant increase in SI in children, taking muscle strength and SB into account. Our results support the importance of assessing accelerometer-based PA in large-scale studies. This may be important when deriving dose–response relationships between PA and bone health in children.

Association between vitamin D status and serum parathyroid hormone concentration and calcaneal stiffness in Japanese adolescents: sex differences in susceptibility to vitamin D deficiency.

There is currently insufficient information on serum 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) concentrations, and bone mineral status in healthy adolescents to allow reference values to be set. This study aimed to provide comparable data on vitamin D status in Japanese adolescents and to assess sex differences in susceptibility to vitamin D insufficiency. Serum 25OHD and PTH concentrations were measured in 1,380 healthy adolescents (aged 12-18years). Subjects completed a questionnaire on exercise history, diet, and lifestyle factors. Calcaneal stiffness was evaluated by quantitative ultrasound. Serum 25OHD concentrations in boys and girls were 60.8±18.3 and 52.8±17.0nmol/L, respectively. Approximately 30% of boys and 47% of girls had suboptimal 25OHD concentrations (<50nmol/L). Serum PTH concentration was negatively correlated with serum 25OHD concentration in boys, but negatively correlated with calcium intake rather than serum 25OHD in girls. In contrast, the increment in calcaneal stiffness as a result of elevation of serum 25OHD was higher in girls than in boys. As vitamin D deficiency is common in Japanese adolescents, it was estimated that intakes of ≥12 and ≥14μg/day vitamin D would be required to reach 25OHD concentrations of 50nmol/L in boys and girls, respectively. Moreover, the results of the present study indicate that vitamin D deficiency has a greater association with calcaneal stiffness in girls than in boys.

Impact of NRTI backbone on renal, bone and cardiovascular markers in HIV-infected individuals receiving a boosted protease inhibitor.

IntroductionWe have previously shown in the SSAT 044 study that unconjugated hyperbilirubinaemia in subjects receiving a boosted protease inhibitor (PI/r) has limited impact on renal, cardiovascular (CV) and bone biomarkers, as well as on neurocognitive performance, relative to those receiving PI/r with a normal bilirubin. We present here a secondary analysis comparing markers in those receiving abacavir- vs tenofovir- based antiretroviral therapy (ART).Materials and MethodsThis cross-sectional study included 101 HIV-1 infected individuals stable (HIV RNA<50 cps/ml, >6 months) on antiretroviral regimens including tenofovir (TDF)/emtricitabine or abacavir/lamivudine plus a ritonavir boosted PI.ResultsForty-three subjects had normal bilirubin (NBR) levels and 35 had high bilirubin (>2.5 times upper limit); the remaining 23 patients had intermediate bilirubin levels or violated the protocol. The mean age of participants was 48 years; 93% were male and 84% Caucasian; 22 received ABC-based therapy and 78 TDF. No differences were seen in cardiovascular markers: Framingham (10-year risk % median, IQR): ABC 8.1, 5.6–15.3; TDF 9.5, 4.8–13.4 (p=ns); pulse wave velocity and carotid intimal thickness also showed no significant differences. No differences were seen in bone parameters: Calcaneal Stiffness Index (median score, IQR): ABC −0.5, −0.8 to 0.8; TDF −0.5, 1.4–0.4 (p=ns); 10 year FRAX score (% median, IQR): ABC 5.0, 2.4–6.2; TDF 3.6, 2.5–5.8 (p=ns). There were differences in renal parameters as shown in Table 1. We show statistically significant differences in urine protein/creatinine ratio (uPCR) (10 vs 7; p=0.004) and urine albumin/creatinine ratio (uACR) (15 vs 8; p=0.002), with both being higher in the TDF group.ConclusionsTenofovir use is associated with excess loss of proteins including those typically resorbed in the renal tubule. Abacavir use was not associated with an increase in biomarkers of CV risk or vascular dysfunction.

Influence of birth weight on calcaneal bone stiffness in Belgian pre-adolescent children

The aim of this study was to investigate the relation between birth weight and calcaneal bone stiffness in a large sample of Belgian, healthy, preadolescent children. Participants were 827 children (3.6–11.2 years, 51.6 % boys) from the Belgian cohort of the IDEFICS study. Birth weight was obtained using a parental questionnaire, and quantitative ultrasound (QUS) measurements were performed to determine calcaneal broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) using the Lunar Achilles device. Average birth weights were 3435.7 ± 512.0 g for boys and 3256.9 ± 471.1 g for girls. Average calcaneal QUS measurements were 89.6 ± 24.0 (23.3–153.9) dB/MHz for BUA, 1621.4 ± 49.6 (1516.3–1776.5) m/s for SOS, and 92.8 ± 15.6 (49.0–163.0) for SI. Birth weight was positively associated with BUA (r = 0.13, p = 0.002) and SOS (r = –0.16, p < 0.001). The associations remained after correcting for age and sex in multiple regression analyses but disappeared after correcting for anthropometric covariates. Our findings suggest that birth weight, as a rough proxy indicator for genetic and environmental influences during intrauterine life, is associated with BUA and SOS in preadolescent children and may therefore influence the risk of osteoporosis later in life. Further studies using QUS are needed to investigate the consistency of the results of this study.

Sclerostin in institutionalized elderly women: associations with quantitative bone ultrasound, bone turnover, fractures, and mortality.

To evaluate the association between levels of circulating sclerostin (an emerging biomarker and important regulator of bone formation) and laboratory parameters of bone and mineral metabolism, bone mineral density and quality measured using quantitative ultrasound (QUS), fracture risk, and mortality. Prospective cohort study. Austrian nursing homes (N = 95). Female nursing home residents aged 70 and older (mean 84 ± 6; N = 539). Serum sclerostin, bone turnover markers, and bone mineral density and quality were measured at baseline. Participants were followed for clinical fractures and all-cause mortality. Partial correlation analysis adjusted for age, weight, and renal function revealed a significant positive correlation between sclerostin levels and calcaneal stiffness and radial and phalangeal speed of sound (all P < .01) and a significant negative correlation between sclerostin levels and osteocalcin, serum C-terminal telopeptide of type I collagen, and parathyroid hormone (PTH; P < .05). After a mean follow-up of 27 ± 8 months, 139 participants (26%) had died and 64 had a hip or other nonvertebral fracture (12%). Sclerostin was not predictive of mortality. In women with a negative fracture history, it was significantly but not linearly associated with fracture risk. In institutionalized elderly women, there is a significant relationship between serum sclerostin levels and QUS indices, bone turnover, and PTH, but sclerostin was not strongly associated with important clinical outcomes. Thus, it remains unclear whether sclerostin is a clinically useful predictor of fractures or mortality, at least in this setting.

Relationship Between Markers of Body Fat and Calcaneal Bone Stiffness Differs Between Preschool and Primary School Children: Results from the IDEFICS Baseline Survey

The aim of this study was to investigate the relationship between markers of body fat and bone status assessed as calcaneal bone stiffness in a large sample of European healthy pre- and primary school children. Participants were 7,447 children from the IDEFICS study (spread over eight different European countries), age 6.1±1.8years (range 2.1-9.9), 50.5% boys. Anthropometric measurements (weight, height, bioelectrical impedance, waist and hip circumference, and tricipital and subscapular skinfold thickness) as well as quantitative ultrasonographic measurements to determine calcaneal stiffness index (SI) were performed. Partial correlation analysis, linear regression analysis, and ANCOVA were stratified by sex and age group: preschool boys (n=1,699) and girls (n=1,599) and primary school boys (n=2,062) and girls (n=2,087). In the overall study population, the average calcaneal SI was equal to 80.2±14.0, ranging 42.4-153. The results showed that preschool children with higher body fat had lower calcaneal SI (significant correlation coefficients between -0.05 and -0.20), while primary school children with higher body fat had higher calcaneal SI (significant correlation coefficients between 0.05 and 0.13). After adjusting for fat-free mass, both preschool and primary school children showed an inverse relationship between body fat and calcaneal stiffness. To conclude, body fat is negatively associated with calcaneal bone stiffness in children after adjustment for fat-free mass. Fat-free mass may confound the association in primary school children but not in preschool children. Muscle mass may therefore be an important determinant of bone stiffness.

Quantitative ultrasound and radiographic absorptiometry are associated with vertebral deformity in Japanese Women: the Hizen–Oshima study

We evaluated the ability of heel quantitative ultrasound (QUS) and metacarpal radiographic absorptiometry (RA) to identify subjects with vertebral deformities in Japanese women aged ≥40. Both QUS and RA were associated with vertebral deformities, and the estimated prevalence at each T-score widely varied with age. Heel QUS and metacarpal RA have been used for screening patients to evaluate risk of osteoporotic fractures. The aim of this study was to evaluate the ability of QUS and RA to identify women with vertebral deformities in 570 Japanese women aged ≥40, and to estimate the prevalence of vertebral deformity at each T-score. Calcaneal QUS and metacarpal RA were performed. Radiographic vertebral deformities were assessed by quantitative morphometry, defined as vertebral heights more than 3 SD below the normal mean. The receiver operating characteristic analysis showed that both calcaneal stiffness index (SI) and metacarpal bone mineral density (BMD) were associated with vertebral deformities. Using the T-score of -2.5 as a cutoff value, the specificity and sensitivity for identifying individuals with vertebral deformities was 65% and 83% for calcaneal SI, and 40% and 88% for metacarpal BMD, respectively. The prevalence of vertebral deformity was estimated using age-adjusted logistic regression models. Women with calcaneal SI T-score of -2.5 had a 2% estimated probability of vertebral deformity at age 40, and 22% at age 80. For metacarpal BMD T-score of -2.5, estimated probability was less than 1% at age 40, and 27% at age 80. Both calcaneal SI and metacarpal BMD were associated with prevalence of vertebral deformity. Furthermore, the prevalence widely varied with age at any given bone value.

Psychosocial Factors Influencing Calcium Intake and Bone Quality in Middle School Girls

Calcium intake has been associated with promoting bone health in children and adolescents, thus preventing osteoporosis later in life. Behavior change such as increased calcium intake, as well as physiological factors such as bone quality, may be facilitated by psychosocial and environmental factors. The purpose of this study was to identify pathways by which psychosocial factors influence calcium intake and bone quality in middle school girls. The study design was cross-sectional. Baseline data from the Incorporating More Physical Activity and Calcium in Teens (IMPACT) study, collected in 2001-2003, were used. IMPACT was a 1.5-year nutrition and physical activity intervention study, designed to improve bone density in 717 middle school girls in Texas. Main outcome measures were calcium intake determined using mean milligrams of calcium consumed per day and number of glasses of milk consumed per day, and bone quality determined using a calcaneal stiffness index. Confirmatory factor analysis and path analysis were performed to identify the direct and indirect pathways used by various psychosocial factors such as knowledge, self-efficacy, outcome expectations, and milk availability at home, to influence calcium intake and bone quality. Results showed that knowledge of osteoporosis and calcium-rich foods had an indirect effect on calcium intake, with outcome expectations as the mediating variable (β=.035 and β=.03, respectively; P<0.05). Calcium self-efficacy had a significant indirect effect on calcium intake, with outcome expectations as the mediator (β=.085, P<0.05). None of the variables significantly influenced bone quality. Thus, several direct and indirect pathways used to influence calcium intake among adolescent girls were identified. These findings are critical for the development of effective interventions to promote calcium intake in this population.

Polymorphisms of the Vitamin D Receptor Gene and Stress Fractures

Our aim was to evaluate the association between VDR polymorphisms and calcaneal Stiffness Index (SI) with stress fractures in a case control study including male military personnel. Thirty- two patients with stress fractures were matched with 32 uninjured healthy volunteers (controls), by gender, age, height, body weight, and level of physical activity. The two groups were genotyped for the FokI, BsmI, ApaI, and TaqI polymorphisms of the VDR gene with PCR-RFLP method. In addition, calcaneal SI was measured by heel quantitative ultrasound in both groups. Data were analyzed by chi-squared test and logistic regression analysis. The f allele was significantly more frequent in patients than in controls (p=0.013), while the B allele showed such a tendency without reaching statistical significance (p=0.052). Among the entire cohort, a 2.7-fold and a 2.0-fold increase in risk of stress fractures was associated with the f and B alleles (OR, 2.7, 95% CI, 1.2-5.9; p=0.014 and OR, 2.0, 95% CI, 1.0-4.1; p=0.053, respectively). No statistically significant association was found between the incidence of stress fractures and t or a alleles. Decreased T-scores were also associated with the presence of f and B alleles. Mean values of T-scores of SI were statistically significantly lower in patients than in controls (p=0.018). These results suggest that the FokI and BsmI polymorphisms of the VDR gene could be associated with increased risk of stress fractures among military personnel. Moreover, a low calcaneal SI could represent a measurable index of this increased risk.

Stress Fractures in Military Men and Bone Quality Related Factors

The aetiology of stress fractures is multifactorial, and many risk factors have been implicated. The aim of this study was to explore the relationship between stress fractures, factors and biochemical markers related to bone metabolism, and calcaneal stiffness index measured by quantitative ultrasound in a case control study including male military personnel beyond basic training. Thirty-two male patients with stress fractures were matched with 32 uninjured-healthy volunteers by age, height, body weight and level of physical performance. A questionnaire concerning the calcium intake, alcohol consumption and smoking was completed, the values of several biochemical markers were measured from blood samples, and calcaneal quantitative ultrasound was measured by heel ultrasound for all participants. Statistically significant higher levels of albumin (4.59 +/- 0.28 vs. 4.40 +/- 0.25, p = 0.006) and lower levels of serum osteocalcin (6.26 +/- 1.74 vs. 7.40 +/- 1.80, p = 0.012), mean values of T-scores (- 0.21 +/- 0.95 vs. 0.33 +/- 0.82, p = 0.018) and Z-scores (- 0.14 +/- 0.81 vs. 0.33 +/- 0.71, p = 0.016) were found among patients compared to controls. Based on the results, it seems that a decreased bone turnover and a low calcaneal stiffness index may be related to the incidence of stress fractures amongst male military personnel.