Femoral neck-shaft angle and climate-induced body proportions.

OBJECTIVES: Declination in femoral neck-shaft angle (NSA) is commonly linked to an increased level of physical activity during life. More recently, however, research suggests that lower NSA might also be explained, in part, as the mechanical consequence of differences in ecogeographic body proportions. This study tests the proposed link between NSA and climatic-induced body proportions, using relative body mass (RBM), throughout the course of development. MATERIALS AND METHODS: NSA and RBM were collected for 445 immature remains from five geographic locations. NSA and RBM were standardized for age-effects. ANOVA was used to examine when population differences emerged in both NSA and RBM. Regression analyses were used to examine the pattern of relationship between NSA and RBM. RESULTS: Populations differ significantly in NSA and RBM before skeletal maturity, and these differences occur early in life. While both NSA and RBM change over the course of development, no significant relationship was found between NSA and RBM for any sample, or any age category (p = .244). DISCUSSION: Individuals who have relatively greater relative body mass do not necessarily have lower NSA. Population differences in NSA were found to be variable, while differences in RBM remained consistent across the developmental span. Taken together, these results suggest that regardless of body proportions, the degree of declination of NSA is presumed to be similar among individuals with similar gait and ambulatory behaviors. Conversely, populations differ in RBM from birth, and these differences are consistent throughout development. These two measures likely are responsive to diffing stimuli, and any potential relationship is likely complex and multifactorial.

Yerba Mate (Ilex paraguariensis) consumption is associated with higher bone mineral density in postmenopausal women.

Yerba Mate (Ilex paraguariensis) tea consumption is higher in Argentina and other South American countries than those of coffee or tea (Camellia sinensis). The effects of Yerba Mate on bone health have not previously been explored. From a program for osteoporosis prevention and treatment, postmenopausal women who drank at least 1 L of Yerba Mate tea daily during 4 or more years (n=146) were identified, and matched by age and time since menopause with an equal number of women who did not drink Yerba Mate tea. Their bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and femoral neck. Yerba Mate drinkers had a 9.7% higher lumbar spine BMD (0.952 g/cm(2) versus 0.858 g/cm(2): p<0.0001) and a 6.2% higher femoral neck BMD (0.817 g/cm(2) versus 0.776 g/cm(2); p=0.0002). In multiple regression analysis, Yerba Mate drinking was the only factor, other than body mass index, which showed a positive correlation with BMD at both the lumbar spine (p<0.0001) and the femoral neck (p=0.0028). Results suggest a protective effect of chronic Yerba Mate consumption on bone.

Baseline glucocorticoid dose and bone mineral density response with teriparatide or alendronate therapy in patients with glucocorticoid-induced osteoporosis.

OBJECTIVE: This post-hoc analysis studied the effect of baseline glucocorticoid dose on the 18-month bone mineral density (BMD) response to teriparatide 20 microg/day or alendronate 10 mg/day in 387 patients with glucocorticoid-induced osteoporosis (GIO) from a randomized, double-blind trial. METHODS: Lumbar spine (LS), femoral neck (FN), and total hip (TH) BMD were measured at baseline and 18 months. Mean baseline glucocorticoid dose was categorized as low (< or = 5 mg/day), medium (> 5 and < 15 mg/day), or high (> or = 15 mg/day). RESULTS: Baseline LS, FN, and TH BMD were similar between groups, and between glucocorticoid dose categories within each group. LS BMD increases at the low, medium, and high glucocorticoid doses were 8.1%, 6.6%, and 4.6%, respectively, with teriparatide, and 3.6%, 2.8%, and 2.3% with alendronate. Analyzed as a continuous variable, higher glucocorticoid doses had a negative, but non-significant, effect on the percentage increase in LS BMD in both groups. Glucocorticoid dose did not significantly affect FN or TH BMD increases in either group. Across the 3 glucocorticoid dose categories, the overall LS BMD increases were different for both treatments combined (p = 0.033), but the relative differences between the treatment groups were not different (interaction, p = 0.52). CONCLUSION: Teriparatide and alendronate increased LS and hip BMD across a range of baseline glucocorticoid doses. LS BMD increases with teriparatide were greater in the low-dose category than in the high-dose category. Overall LS BMD increases were significantly greater with teriparatide compared with alendronate, which may reflect the respective anabolic and antiresorptive mechanisms of action. Clinical Trial Registry Number: NCT00051558.

Determinants of bone mass and size in 7-year-old former term, late-preterm, and preterm boys.

UNLABELLED: When compared, full-term prepubertal boys had greater regional bone size, higher total body (TB) bone mineral content (BMC), and regional bone density than preterm boys but higher TB bone content area and regional BMC than late-preterm boys. Implications include follow-up bone assessment and preterm formula feeding in late-preterm boys. INTRODUCTION: This study was conducted to determine whether there are differences in bone mass and size among prepubertal boys born preterm (PT; < or =34 weeks gestation), late-preterm (LP; >34 and < or =37 weeks gestation), and at term (>37 weeks gestation) and to identify factors that are associated with bone mass and size in these children. METHODS: Total body (TB), spine and hip dual energy X-ray absorptiometry and tibia peripheral quantitative computed tomography measures were obtained on 24 boys aged 5.7 to 8.3 years. RESULTS: In multiple regression analysis adjusting for current weight, height, age, and jump power, term boys had greater cortical thickness (p = 0.03) and area (p = 0.01), higher trabecular volumetric bone mineral density (p = 0.05), TB bone mineral content (BMC; p = 0.007), and hip areal bone mineral density (aBMD; p = 0.01) than PT boys, and higher TB BMC (p = 0.01), TB bone area (p = 0.03), hip BMC (p = 0.02) and aBMD (p = 0.01), and femoral neck BMC (p = 0.05) and aBMD (p = 0.02) than LP boys. There were no differences in activity measures among gestation groups and no group-by-activity interactions. CONCLUSION: Term boys have greater bone size and mass than PT boys and higher bone mass than LP boys at several bone sites. Activity measures did not differ among gestation groups and did not explain bone differences.

Effect of high molecular weight water-soluble chitosan on the trabecular bone and thickness in ovariectomized rats.

High molecular weight water-soluble chitosan(WSC), having an average molecular weight of 300,000 Da and a degree of deacethylation over 90%, can be produced using a simple multi-step membrane separation process. In this study, the trabecular bone area and thickness in ovariectomized(OVX) rats decreased by almost 50% from those in sham-operated rats. WSC was evaluated for inhibition of the progress of bone loss induced by OVX rats. We measured bone histomorphometry in sham, OVX or WSC-administered OVX rats. From light microscopic analyses, a porous or erosive appearances were observed on the surface of trabecular bone of tibia in OVX rats, whereas those of the same bone in sham-operated rats were composed of fine particles. The trabecular bone area and trabecular thickness in OVX rats decreased by 50% from those in sham rats, these decreases were completely inhibited by administration of WSC at a concentration of 15 mg/kg/daily for 7 weeks. In this study, the mechanical strength in femur neck was significantly enhanced by the treatment of WSC for 7 weeks. In OVX rats, free T(3) was normal in all cases, whereas free T(4) was significantly increased. Although there was no difference between OVX and WSC-administered rats in T(3) level, we have found significant difference between them in T(4) level. These results strongly suggest that WSC is effective in preventing the development of bone loss induced by OVX in rats.

One year of oral calcium supplementation maintains cortical bone density in young adult female distance runners.

We conducted a double-blind, placebo-controlled, randomized trial to determine whether 1 year of supplemental calcium intake would augment hip [greater trochanter, GT, femoral neck (FN), total hip (TH)], spine (LS), and femoral mid-shaft (Fmr) BMD in female distance runners. Twenty-three women (age: 23.7 +/- 4.7 yrs, height: 165.6 +/- 6.3 cm, weight: 55.7 +/- 6.1 kg) were randomly assigned to receive either 1000 mg/d of supplemental calcium (N = 13) or placebo tablets (N = 10) for 1 year. BMD was determined by DXA (Hologic 1000-W) and tablet compliance by self-report logs. Compliance averaged 79% and 71% for supplement and placebo groups, respectively. Calcium supplementation did not affect hip or spine BMD, but did prevent loss at the femoral mid-shaft (GT: -0.5% vs. 0.2%, FN: 0.9% vs. 1.1%, TH: -0.3% vs. 0.2%, LS: 0.3% vs. 1.2%, Fmr: 0.1% vs. -1.8%, for calcium vs. placebo, respectively). We conclude that the addition of 800 mg/d of supplemental calcium to the diet of young adult female distance runners with habitual calcium intakes of approximately 1000 mg/d, prevents cortical but not trabecular bone loss.

Vitamin K intake and bone mineral density in women and men.

BACKGROUND: Low dietary vitamin K intake has been associated with an increased risk of hip fracture in men and women. Few data exist on the association between dietary vitamin K intake and bone mineral density (BMD). OBJECTIVE: We studied cross-sectional associations between self-reported dietary vitamin K intake and BMD of the hip and spine in men and women aged 29-86 y. DESIGN: BMD was measured at the hip and spine in 1112 men and 1479 women (macro x +/- SD age: 59 +/- 9 y) who participated in the Framingham Heart Study (1996-2000). Dietary and supplemental intakes of vitamin K were assessed with the use of a food-frequency questionnaire. Additional covariates included age, body mass index, smoking status, alcohol use, physical activity score, and menopause status and current estrogen use among the women. RESULTS: Women in the lowest quartile of vitamin K intake (macro x: 70.2 microg/d) had significantly (P < or = 0.005) lower mean (+/- SEM) BMD at the femoral neck (0.854 +/- 0.006 g/cm(2)) and spine (1.140 +/- 0.010 g/cm(2)) than did those in the highest quartile of vitamin K intake (macro x: 309 microg/d): 0.888 +/- 0.006 and 1.190 +/- 0.010 g/cm(2), respectively. These associations remained after potential confounders were controlled for and after stratification by age or supplement use. No significant association was found between dietary vitamin K intake and BMD in men. CONCLUSIONS: Low dietary vitamin K intake was associated with low BMD in women, consistent with previous reports that low dietary vitamin K intake is associated with an increased risk of hip fracture. In contrast, there was no association between dietary vitamin K intake and BMD in men.

Does body size account for gender differences in femur bone density and geometry?

The extent to which greater bone strength in men is caused by proportionately greater bone mass versus bigger bone size is not clear, primarily because the larger overall body size of men has made direct comparisons of skeletal measures difficult. We examined gender differences in femur neck (FN) areal bone mineral density (BMD) values collected from 5,623 non-Hispanic whites aged 20+ years in the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994) before and after correction for measured height and weight. We supplemented the conventional areal BMD data (Hologic QDR 1000) with measurements of areal BMD and geometric properties (subperiosteal width, section modulus, and cortical thickness) made at narrow "cross-sectional" regions traversing the FN and the proximal shaft using a structural analysis program. Before body size adjustment, men had significantly higher values than women for all variables at the three measurement sites (p < 0.0001). Adjustment for body size reduced the differences between the sexes for all variables but had a greater effect on BMD (1-8% higher in men) than on geometry (5-17% higher in men). When examined by age, the sex discrepancy was significantly greater in the older group for all variables except subperiosteal widths. We conclude that although body size difference may account for most of the areal BMD difference between men and women, male bones are still bigger in ways that suggest greater bone strength. These differences may contribute importantly to lower fracture risk in men.

Patterns of sexual, bilateral and interpopulational variation in human femoral neck-shaft angles.

Data on femoral neck-shaft angles were collected for 30 modern, historic and prehistoric human population samples, and analysed with respect to sexual dimorphism, bilateral asymmetry, geographical patterning and general economic level. Although some samples had modest sexual dimorphism in this angle, and some individuals exhibited clear asymmetry, there were no consistent patterns of sexual or side differences across human populations. Similarly, there was no evidence for geographic differences, since broad regional groups lacked significant differences and mean angles were not correlated with latitude. However, there is a significant increase in mean neck-shaft angles across populations with an increasingly sedentary existence and with mechanisation. The last reflects the developmental plasticity of this feature with respect to habitual load levels during ontogeny of the hip region.