Radius Bone Mineral Density Research Articles

260 Are Type 1 Diabetes Children and Adolescents at Risk for An Impaired Bone Mineralization?

Aim: Diabetic adolescents, particularly girls, often show poor metabolic control. The aim of this study is to investigate whether glycemic control (GC) during puberty has an influence on radial trabecular bone mineral density (BMD) at the final growth. Methods: We studied 52 adolescent type 1 diabetes mellitus (DM1) (24 females) at the end of puberty. Median (range) age was 18.4 (17.2-24.8). Duration of diabetes ranged between 1.4-19.9 years (median 9.1). Trabecular BMD of the distal radius was investigated using peripheral quantitative computed tomography (XCT-2000, Stratec, Germany). Mean glycosylated hemoglobin (HbA1c) in the last 4 years (13.8±3.9 measurements per patient) was calculated as GC parameter. We recruited 44 healthy controls (C) (32 females; similar age range). Results: In males DM1 and C subjects had similar height, weight, body mass index (BMI), trabecular BMD and age-adjusted trabecular BMD values (Z-score). Female DM1 patients had a significant higher BMI Z-score (0.51±0.84 vs. -0.11±0.95; p=0.01) and a significant lower trabecular BMD (175.7±30.6 vs. 195.2±32.7mg/cm2; p=0.03) and Z-score (-0.55±0.87 vs. 0.03±0.92; p=0.02). Only 2 DM1 females and none of the males had a trabecular BMD Z-score < -2. Mean HbA1c was significantly higher in female patients (8.68±1.19 vs. 7.83±1.24%; p=0.02). HbA1c ranged between 6.0-10.8% and was negatively correlated with trabecular BMD Z-score (r=-0.15; p=0.3), but correlation was not significant. Conclusions: Whereas diabetes type 1 females, compared to healthy controls, have a lower trabecular bone mineralization at the end of puberty, the majority of adolescent DM1 patients have a trabecular BMD within normal range.

Pathway-based genome-wide association analysis identified the importance of regulation-of-autophagy pathway for ultradistal radius BMD

Wrist fracture is not only one of the most common osteoporotic fractures but also a predictor of future fractures at other sites. Wrist bone mineral density (BMD) is an important determinant of wrist fracture risk, with high heritability. Specific genes underlying wrist BMD variation are largely unknown. Most published genome-wide association studies (GWASs) have focused only on a few top-ranking single-nucleotide polymorphisms (SNPs)/genes and considered each of the identified SNPs/genes independently. To identify biologic pathways important to wrist BMD variation, we used a novel pathway-based analysis approach in our GWAS of wrist ultradistal radius (UD) BMD, examining approximately 500,000 SNPs genome-wide from 984 unrelated whites. A total of 963 biologic pathways/gene sets were analyzed. We identified the regulation-of-autophagy (ROA) pathway that achieved the most significant result (p = .005, qfdr = 0.043, pfwer = 0.016) for association with UD BMD. The ROA pathway also showed significant association with arm BMD in the Framingham Heart Study sample containing 2187 subjects, which further confirmed our findings in the discovery cohort. Earlier studies indicated that during endochondral ossification, autophagy occurs prior to apoptosis of hypertrophic chondrocytes, and it also has been shown that some genes in the ROA pathway (e.g., INFG) may play important roles in osteoblastogenesis or osteoclastogenesis. Our study supports the potential role of the ROA pathway in human wrist BMD variation and osteoporosis. Further functional evaluation of this pathway to determine the mechanism by which it regulates wrist BMD should be pursued to provide new insights into the pathogenesis of wrist osteoporosis. © 2010 American Society for Bone and Mineral Research.

Bone mineral density and bone fracture in male patients receiving long-term suppressive levothyroxine treatment for differentiated thyroid carcinoma

Studies on the effect of exogenous subclinical thyrotoxicosis on bone mineral density (BMD) in male patients treated with suppressive doses of levothyroxine for differentiated thyroid carcinoma (DTC) are not conclusive. In order to evaluate BMD (in femoral neck, lumbar spine, and distal radius) and bone fractures in men under long-term suppressive treatment with levothyroxine for DTC, we conducted a cross-sectional, retrospective study in 33 Caucasian men (mean±SD age: 56±14years) under treatment for DTC. The control group comprised 33 healthy age- and body mass index-matched male volunteers. BMD was assessed by dual-energy X-ray absorptiometry (DXA). Bone turnover biomarkers (calcium, phosphate, alkaline phosphatase, PTH, vitamin D, urinary calcium, and N-Telopeptide/creatinine index) and testosterone were determined. Previous bone fractures were evaluated with a questionnaire and X-ray images of thoracic and lumbar vertebrae. Patients were treated for a mean duration of 15±5years. No differences were found between patients and controls in bone turnover biomarkers or areal BMD, T-scores or Z-scores in all sites evaluated. No earlier fractures or pain episodes were registered in either group and the incidence of asymptomatic vertebral fractures did not differ significantly between patient (18.8%) and control groups (16.7%), (P=0.9). In conclusion, long-term suppressive treatment with levothyroxine in men with DTC does not appear to exert deleterious effects on bone mineral density or increase the prevalence of fracture.

A Cross-Sectional Evaluation of the Effect of Risperidone and Selective Serotonin Reuptake Inhibitors on Bone Mineral Density in Boys

The aim of the present study was to investigate the effect of risperidone-induced hyperprolactinemia on trabecular bone mineral density (BMD) in children and adolescents. Medically healthy 7- to 17-year-old males chronically treated, in a naturalistic setting, with risperidone were recruited for this cross-sectional study through child psychiatry outpatient clinics between November 2005 and June 2007. Anthropometric measurements and laboratory testing were conducted. The clinical diagnoses were based on chart review, and developmental and treatment history was obtained from the medical record. Volumetric BMD of the ultradistal radius was measured using peripheral quantitative computed tomography, and areal BMD of the lumbar spine was estimated using dual-energy x-ray absorptiometry. Hyperprolactinemia was present in 49% of 83 boys (n = 41) treated with risperidone for a mean of 2.9 years. Serum testosterone concentration increased with pubertal status but was not affected by hyperprolactinemia. As expected, bone mineral content and BMD increased with sexual maturity. After adjusting for the stage of sexual development and height and BMI z scores, serum prolactin was negatively associated with trabecular volumetric BMD at the ultradistal radius (P < .03). Controlling for relevant covariates, we also found treatment with selective serotonin reuptake inhibitors (SSRIs) to be associated with lower trabecular BMD at the radius (P = .03) and BMD z score at the lumbar spine (P < .05). These findings became more marked when the analysis was restricted to non-Hispanic white patients. Of 13 documented fractures, 3 occurred after risperidone and SSRIs were started, and none occurred in patients with hyperprolactinemia. This is the first study to link risperidone-induced hyperprolactinemia and SSRI treatment to lower BMD in children and adolescents. Future research should evaluate the longitudinal course of this adverse event to determine its temporal stability and whether a higher fracture rate ensues.

Changes in trabecular microarchitecture in postmenopausal women on bisphosphonate therapy

Purpose In addition to bone mineral density (BMD), trabecular microstructure contributes to skeletal strength. Our goal was to examine changes in trabecular microstructure in women on therapy. Materials and methods We followed 10 postmenopausal women receiving a bisphosphonate, risedronate (35 mg once weekly), over 12 months and examined trabecular microarchitecture with high resolution wrist MR images (hr-MRI). MRI parameters included bone volume/total volume (BV/TV), surface density (representing plates), curve density (representing rods), surface-to-curve ratio and erosion index (depicting deterioration). We assessed BMD of the spine, hip and radius and markers of bone turnover. Results Women had been receiving bisphosphonate therapy for 43 ± 9 months (mean ± SD) prior to the first MRI. Indices of hr-MRI demonstrated improvement in surface-to-curve ratio (13.0%) and a decrease in erosion index (12.1%) consistent with less deterioration (both p < 0.05). BMD of the spine, hip and radius and markers of bone turnover remained stable. Parameters of hr-MRI were associated with 1/3 distal radius BMD (correlation coefficient 0.71 to 0.86, p < 0.05). Discussion We conclude that hr-MRI of the radius demonstrates improvements in trabecular microstructure not appreciated by conventional BMD and provides additional information on parameters that contribute to structural integrity in patients on antiresorptive therapy.

Association Among Serum Fetuin‐A Level, Coronary Artery Calcification, and Bone Mineral Densitometry in Maintenance Hemodialysis Patients

Patients with end-stage renal disease have a very high prevalence and extent of arterial calcification. A number of studies suggest that similar pathophysiologic mechanisms are responsible for development and progression of calcification of atherosclerotic plaque and bone formation. Fetuin-A is a potent calcification inhibitor and is expressed in bone, with not-yet well-defined functions. The aim of this study was to investigate the relation between bone mineral densitometry parameters, coronary artery calcification, and serum fetuin-A levels. In a cross-sectional design, we included 72 maintenance hemodialysis (HD) patients and 30 age- and gender-matched healthy controls. Serum fetuin-A levels were studied both in maintenance HD patients and healthy controls. Maintenance HD patients had radius, hip, and lumbar spine bone mineral density (BMD) assessed by dual-energy X-ray absorptiometry and coronary artery calcification score (CACS) measured by electron-beam computed tomography. The associations between site-specific BMD parameters, CACS, and serum fetuin-A levels were studied in maintenance HD patients. CACS, mass, and volume of plaques in coronary arteries were significantly higher in patients with a T-score below -2.5 than above in the proximal region of the radius, neck and trochanter of the femur, and the lumbar spine. Mean serum fetuin-A concentration was 0.636 +/- 0.118 g/L in maintenance HD patients and it was less than healthy controls (0.829 +/- 0.100 g/L, P < 0.0001). CACS, mass, and volume of plaques in coronary arteries correlated significantly with the serum fetuin-A levels. Moreover, significant positive correlations were shown between the serum fetuin-A levels, BMD values, and T-scores of proximal radius, neck, and trochanter of the femur, but not with the lumbar spine. The present study demonstrates an association between serum fetuin-A levels, coronary artery calcification, and bone mineral densities--except for the lumbar spine, in maintenance HD patients. However, the results should be interpreted with caution because of the cross-sectional design of the study.

Lower bone mineral density of forearm in postmenopausal patients with radiographic hand osteoarthritis

The association between clinical parameters and forearm bone mineral density (BMD) in postmenopausal females with radiographic hand OA has not been determined. We investigated the difference in forearm BMD between radiographic hand OA and non-radiographic hand OA, and also the association between clinical parameters of patients and the level of forearm BMD. A total of 180 postmenopausal patients with hand OA were enrolled in this study. We classified them into two groups according to the Kellgren-Lawrence (K-L) radiological grade, one with radiographic hand OA (K-L grade > or = 2) and the other with non-radiographic OA (K-L grade < 2) as controls. The number of nodal joints, swollen joints and tender joints were determined in the physical examination, and measures of BMD (g/cm(2)), Australian Canadian (AUSCAN) OA hand index, grip strength, pinch strength, and visual analogue scale (VAS) were also estimated. Patients with radiographic hand OA had lower distal radius BMD when compared with controls (0.35 +/- 0.06 vs. 0.40 +/- 0.05, P < 0.001). After adjusting for variables such as age, menopausal duration, number of nodal joints, and AUSCAN function index, the difference in BMD between the two groups was also significantly different (0.35 +/- 0.04 vs. 0.38 +/- 0.04, P < 0.001). For analysis of risk factors for forearm BMD in hand OA, age and K-L OA grade in total hand OA are considered risk factors, whereas age and menopause duration contribute to the forearm BMD in radiographic hand OA patients (P < 0.001, P = 0.002, respectively). The development of osteoporosis at the distal radius in radiographic hand OA is associated with older age (OR = 1.216, P = 0.002), lower BMI (OR = 0.777, P = 0.004) and lower stiffness in the AUSCAN OA index (OR = 0.505, P = 0.003). This study shows that the BMD levels of the distal radius in patients with radiographic hand OA are significantly lower when compared to those of controls. Forearm BMD levels are positively associated with age and K-L radiological grade in total hand OA, whereas age and menopausal duration are closely related with radiographic hand OA. The presence of osteoporosis in the distal radius in radiographic hand OA may be influenced by age, BMI, and stiffness on the AUSCAN index.

Maternal plasma 25‐hydroxyvitamin D concentration and birthweight, growth and bone mineral accretion of Gambian infants

Maternal plasma 25‐hydroxyvitamin D concentration and birthweight, growth and bone mineral accretion of Gambian infants

Accuracy of volumetric bone mineral density measurement in high-resolution peripheral quantitative computed tomography

Accurate bone mineral density (BMD) quantification is critical in clinical assessment of fracture risk and in the research of age-, disease-, and treatment-related musculoskeletal changes. The development of high-resolution peripheral quantitative computed tomography (HR-pQCT) imaging has made possible in vivo assessment of compartmental volumetric BMD (vBMD) and bone micro-architecture in the distal radius and tibia. HR-pQCT imaging relies on a polychromatic X-ray source and therefore is subject to beam hardening as well as scatter artifacts. In light of these limitations, we hypothesize that the accuracy of HR-pQCT vBMD measurement in the trabecular compartment (vBMD trab) is not independent of bone density and geometry, but rather influenced by variations in trabecular bone volume fraction and cortical thickness. The goal of this study, therefore, was to evaluate the accuracy of HR-pQCT vBMD trab measurement in the radius and tibia, and to determine the dependence of this measurement on geometric and densitometric parameters. Our approach was to use a series of idealized hydroxyapatite (HA) phantoms with varying densities and geometries to quantify the accuracy of HR-pQCT analysis. Two sets of custom-made HA phantoms designed to mimic the distal tibia and distal radius were manufactured. Geometric and densitometric specifications were based on a dataset of healthy volunteers and osteopenic patients. Multiple beam hardening correction (BHC) algorithms were implemented and evaluated in their ability to reduce measurement error. Substantial errors in measured vBMD trab were found. Overestimation of vBMD trab increased proportional to cortical shell thickness and decreased proportional to insert density. The most pronounced vBMD trab overestimation therefore occurred in the phantoms with the lowest insert densities and highest shell thickness, where error was as high as 20 mg HA/cm 3 (33%) in the radius phantom and 25 mg HA/cm 3 (41%) in the tibia phantom. Error in vBMD trab propagates to the calculation of micro-architectural measures; 41% error in vBMD trab will produce 41% error in volume fraction (BV/TV) and trabecular thickness (Tb.Th), and 5% error in trabecular separation (Tb.Sp). BHC algorithms supplied by the manufacturer failed to eliminate these errors. Our results confirm that geometric and densitometric variations influence the accuracy of HR-pQCT vBMD trab measurements, and must be considered when interpreting data across populations or time-points.

Low volumetric BMD is linked to upper-limb fracture in pubertal girls and persists into adulthood: A seven-year cohort study

The aetiology of increased incidence of fracture during puberty is unclear. This study aimed to determine whether low volumetric bone mineral density (vBMD) in the distal radius is associated with upper-limb fractures in growing girls, and whether any such vBMD deficit persists into adulthood. Fracture history from birth to 20 years was obtained and verified by medical records in 1034 Finnish girls aged 10–13 years. Bone density and geometry at distal radius, biomarkers and lifestyle/behavioural factors were assessed in a subset of 396 girls with a 7.5-year follow-up. We found that fracture incidence peaked during puberty (relative risk 3.1 at age of 8–14 years compared to outside this age window), and 38% of fractures were in the upper-limb. Compared to the non-fracture cohort, girls who sustained upper-limb fracture at ages 8–14 years had lower distal radial vBMD at baseline (258.9 ± 37.5 vs. 287.5 ± 34.1 mg/cm 3, p = 0.001), 1-year (252.0 ± 29.3 vs. 282.6 ± 33.5 mg/cm 3, p = 0.001), 2-year (258.9 ± 32.2 vs. 289.9 ± 40.1 mg/cm 3, p = 0.003), and 7-year follow-ups (early adulthood, 307.6 ± 35.9 vs. 343.6 ± 40.9 mg/cm 3, p = 0.002). There was a consistent trend towards larger bone cross-sectional area in the fracture cohort compared to non-fracture. In a logistic regression model, lower vBMD ( p = 0.001) was the only significant predictor of upper-limb fracture during the period of 8–14 years. Our results indicate that low BMD is an important factor underlying elevated upper-limb fracture risk during puberty, and that low BMD in pubertal girls with fracture persists into adulthood. Hence low vBMD during childhood is not a transient deficit. Methods to monitor vBMD and to maximise bone mineral accrual and reduce risks of falling in childhood should be developed.

Upper limb bone mineral density and body composition measured by peripheral quantitative computed tomography in right-handed adults: The role of the dominance effect

To investigate the impact on bone and muscle of pathological conditions involving only one of the upper limbs, it is important to know the physiological differences due to the dominance effect. To evaluate any physiological differences between dominant and non-dominant upper limbs in terms of bone mineral density (BMD), muscle mass, and muscle density at different levels. The study considered 60 right-handed healthy adults, 30 men and 30 women. Cortical BMD, muscle area, and muscle density were investigated by pQCT-XCT-3000 Stratec at the proximal radius, trabecular and total BMD at the distal radius, and trabecular and cortical BMD at the second phalanx of the third finger. Hand grip strength was also measured. No significant differences in BMD were found between the dominant and non-dominant upper limbs at any of the sites considered, in men or women. Muscle density was also similar on the two sides, whereas muscle area at the proximal radius was significantly lower on the non-dominant side in both men [4177.5+/-475.1 vs 4009.3+/-552.7 mm2; Delta%: 4.1%; 95% confidence interval (CI) 1.7%-6.5%] and women (2903.9+/-470.9 vs 2720.3+/-411.7 mm2; Delta%: 6.1%; 95%CI 4.3%-7.9%). Hand grip strength proved greater on the right side in both men (48.5+/-8.8 vs 45.2+/-8.7 kg; Delta% 7.1; p<0.001) and women (29.1+/-4.3 vs 27.0+/-5.1 kg; Delta% 7.1; p<0.001). The dominance effect does not seem to influence trabecular or cortical BMD at any of the sites in the upper limb. Muscle density is not modified by dominance, while muscle area is reduced on the non-dominant side and this should be borne in mind when the effect of pathological conditions on the body composition of a single forearm is investigated.

Impact of alfacalcidol on bone mineral density (pQCT & DXA) of radius, tibia, spine and hip in postmenopausal alendronate treated women with reduced bone mass

Impact of alfacalcidol on bone mineral density (pQCT & DXA) of radius, tibia, spine and hip in postmenopausal alendronate treated women with reduced bone mass

Presentation of Asymptomatic Primary Hyperparathyroidism: Proceedings of the Third International Workshop

At the Third International Workshop on Asymptomatic Primary Hyperparathyroidism (PHPT) in May 2008, recent data on the disease were reviewed. We present the results of a literature review on issues arising from the clinical presentation and natural history of PHPT. Questions were developed by the International Task Force on PHPT. A comprehensive literature search for relevant studies was reviewed, and the questions of the International Task Force were addressed by the Consensus Panel. 1) Data on the extent and nature of cardiovascular involvement in those with mild disease are too limited to provide a complete picture. 2) Patients with mild PHPT have neuropsychological complaints. Although some symptoms may improve with surgery, available data remain inconsistent on their precise nature and reversibility. 3) Surgery leads to long-term gains in spine, hip, and radius bone mineral density (BMD). Because some patients have early disease progression and others lose BMD after 8-10 yr, regular monitoring (serum calcium and three-site BMD) is essential in those followed without surgery. Patients may present with normocalcemic PHPT (normal serum calcium with elevated PTH concentrations; no secondary cause for hyperparathyroidism). Data on the incidence and natural history of this phenotype are limited. 4) In the absence of kidney stones, data do not support the use of marked hypercalciuria (>10 mmol/d or 400 mg/d) as an indication for surgery for patients. 5) Patients with bone density T-score -2.5 or less at the lumbar spine, hip, or distal one third radius should have surgery.

Peripheral quantitative computed tomography is useful to monitor response to alendronate therapy in postmenopausal women

A forearm fracture (Colles' fracture) is often the first sign of osteoporosis and may suggest underlying skeletal fragility. Therefore, establishment of a more accurate and reliable method for the measurement of bone mineral density (BMD) at the distal radius would be beneficial for patients who suffer from osteoporosis. The objective of this study was to evaluate the usefulness of peripheral quantitative computed tomography (pQCT) to monitor the response to alendronate therapy at the distal radius in early postmenopausal Japanese women. Thirty-two early postmenopausal women who were diagnosed with osteoporosis or osteopenia were randomized to either alendronate or control treatment. We analyzed the BMD of the distal radius by pQCT, lumbar spine by dual-energy X-ray absorptiometry (DXA) and the biochemical markers of bone turnover (deoxypyridinoline) at baseline, 3, 6 and 12 months. The control group showed a significant decrease from baseline in the trabecular BMD of the radius at 12 months (3.5 +/- 3.7%; p < 0.01), whereas the alendronate group showed a significant increase (4.3 +/- 8.1%). The changes in the trabecular BMD of the radius between the alendronate and control groups were statistically different at 6 and 12 months (p < 0.01). However, in the total BMD at the diaphysis of the radius, no significant differences were seen in the changes in bone densities between the alendronate and control groups after 1 year of treatment. pQCT detected significant differences in BMD of the radius in early postmenopausal women after 1 year of treatment with alendronate. Collectively, our preliminary clinical trial showed that pQCT might be useful to monitor response to alendronate therapy, especially at the radius, and it might explain why alendronate prevents Colles' fracture.

Microscopic hematuria is associated with low bone mineral density in aged women and men

Little is known concerning renal or urological risk factors for osteoporosis. The aim of this study was to explore an association between urinalysis and bone mineral density (BMD) in 4,835 Japanese adults. Participants were 4,835 individuals (female 3,683; male 1,152) aged 50 years and over who received a health check-up between January 1995 and March 2006 in Japan. BMD of the distal radius and ulna of the non-dominant forearm was measured by the dual-energy X-ray absorptiometry (DXA) method using a DTX-200 Dexacare osteometer (Osteometer MediTech A/S, Rødovre, Denmark). Urine variables were protein, and red blood cells (RBCs) and white blood cells (WBCs) in urine sediment (categorized as <1, 1-4, 5-9, or >or=10 cells per high-power microscopic field). Average age was 58.9 years (SD 5.6) in women, and 60.5 years (SD 6.2) in men. Simple linear regression analysis showed that urinary RBCs were associated with BMD in women (beta = or-5.88 x 10(-3), R (2) = 0.004, p < 0.0001) and men (beta = or-1.34 x 10(-2), R (2) = 0.013, p = 0.0001). These associations held when possible confounders were adjusted (beta = or-2.05 x 10(-3), R (2) = 0.001, p = 0.0338 for women and beta =or -5.67 x 10(-3), R (2) = 0.006, p = 0.0163 for men). Microscopic hematuria is associated with forearm BMD in women and men aged 50 years and over. Further studies should be conducted to determine the mechanisms underlying this association.

84 Enhanced Characterization of the Thickness and Bone Mineral Density of the Radius and Tibia by Low-Frequency Guided-Wave Ultrasound

84 Enhanced Characterization of the Thickness and Bone Mineral Density of the Radius and Tibia by Low-Frequency Guided-Wave Ultrasound

Association Between Changes in Habitual Physical Activity and Changes in Bone Density, Muscle Strength, and Functional Performance in Elderly Men and Women

To investigate the long-term effects of habitual physical activity on changes in musculoskeletal health, functional performance, and fracture risk in elderly men and women. Ten-year prospective population-based study. Malmö-Sjöbo Prospective Study, Sweden. Participants were 152 men and 206 women aged 50, 60, 70, and 80 who were followed for 10 years. Distal radius bone mineral density (BMD) (single photon absorptiometry), upper limb muscle (grip) strength, balance, gait velocity, occupational and leisure-time activity, and fractures (interview-administered questionnaire) were reassessed after 10 years. Annual changes for all measures were compared between participants with varying habitual physical activity histories at baseline and follow-up: inactive-inactive (n=202), active-inactive (n=47), inactive-active (n=49), and active-active (n=60). Data for men and women were pooled, because there were no sex-by-activity group interactions. To detect possible differences in fracture incidence between the varying habitual activity groups, participants were classified into two activity groups based on their activity classification at baseline and follow-up: inactive:less active versus active:more active. The annual rate of bone loss was 0.6% per year less in individuals classified as active at both time points than in those classified as inactive at both time points (P<.01). Similar results were observed for balance, but there was no effect of varying habitual activity on changes in muscle strength or gait velocity. There were also no differences in fracture incidence between individuals categorized as active:more active and those categorized as inactive:less active during the follow-up (adjusted hazard ratio=0.90, 95% confidence interval (CI)=0.42-1.90). This study showed that elderly men and women who maintained a habitually active lifestyle over 10 years had lower bone loss and retained better balance than those who remained habitually inactive.

Habitual Site-Specific Upper Extremity Loading is Associated with Increased Bone Mineral of the Ultradistal Radius in Young Women

Osteoporosis and osteopenia are major contributors to the high incidence of fractures in older women. Habitual loading plays a crucial role in the acquisition and maintenance of bone. It may be possible to develop clinical interventions based on targeted modes of physical loading that can improve bone health and reduce fractures in women. If so, an important first step is determining the degree to which common fracture sites, such as the distal radius are responsive to habitual loading. The bone mineral density (BMD) and bone mineral content (BMC) of the ultradistal radius of 15 female gymnasts were compared with those of an age-matched, mass-matched, and height-matched control group. The hypothesis that the ultradistal radius BMD and BMC in gymnasts would be higher than those of the control group was tested using a 2 x 2 (left/right x group) repeated measures analysis of variance (MANOVA). After adjusting for the between-group difference in the influence of body mass, the gymnasts had 24% larger BMD and a 34% larger BMC at the ultradistal radii than the control group (p < 0.001). These results suggest that the ultradistal radius is responsive to the types and magnitudes of load encountered during gymnastics. A responsive distal radius is a necessary prerequisite to the development of loading-based interventions to increase ultradistal radius bone quality. Such interventions have the potential to significantly increase distal radius strength, thereby reducing the incidence of fracture.

Serum lipid profile: its relationship with osteoporotic vertebrae fractures and bone mineral density in Turkish postmenopausal women

The effect of the serum lipid levels on vertebral fractures and bone mineral density is not clear. A total of 107 postmenopausal women aged 45-79 examined by lumbar spine, hip and radius bone mineral density (BMD) measurements, lateral dorsal and lumbar spine radiographies, routine blood tests and serum lipids [total cholesterol (TC), triglyceride (TG), HDL-C, LDL-C, VLDL-C]. Demographic and lifestyle characteristics were collected. Eighty-nine radiographies with good technical properties were scored by the Kleerekoper method. Patients with vertebrae fractures had lower levels of TC, TG, LDL-C than the patients without vertebrae fractures. Total cholesterol level was the most prominent factor affecting the vertebral fracture existence. An increase of 1 mg/dl total cholesterol decreases the risk of vertebrae fracture by 2.2%. The existence of osteoporosis due to T score was not influencing the lipid values. TC and LDL-C were weakly associated with BMD at the forearm UD region after the adjustment for the possible confounders. This study shows that the serum lipids have impact on vertebrae fracture existence rather than BMD alterations.

Measurement of Trabecular Bone Microstructure Does Not Improve Prediction of Mechanical Failure Loads at the Distal Radius Compared with Bone Mass Alone

Bone mass predicts a high proportion of variability in bone failure strength but is known to overlap among subjects with and without fractures. Here, we tested the hypothesis that trabecular bone microstructure, determined with micro-computed tomography (microCT), can improve the prediction of experimental failure loads in the distal forearm compared with bone mass alone. The right forearm and left distal radius of 130 human specimens were examined. Bone mineral density (BMD) was measured with peripheral dual energy X-ray absorptiometry (DXA). The specimens were mechanically tested to failure in a fall configuration, with the hand, elbow, ligaments, and tendons intact. Cylindrical bone samples from the metaphysis of the contralateral distal radius were obtained adjacent to the subchondral bone plate and scanned with microCT. When analyzing the total sample, BMD of the distal radius displayed a correlation of r = 0.82 with mechanical failure loads. After excluding 21 specimens with no obvious radiological sign of fracture after the test, the correlation increased to r = 0.85. When only including 79 specimens with loco typico fractures, the correlation was r = 0.82. The microstructural parameters showed correlation coefficients with the failure loads of < or =0.55 and did not add significant information to DXA in predicting failure loads in multiple regression models. These findings suggest that, under experimental conditions of mechanically testing entire bones, measurement of bone microstructure does not improve the prediction of distal radius bone strength. Determination of bone microstructure may thus be less promising in improving the prediction of fractures than commonly assumed.