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Summary: In this study of postmenopausal women in Malaysia, total adiposity was inversely associated with total BMD, while regional associations varied. No differences were detected across Malay, Chinese, and Indian ethnicities. Low BMD contributes substantially to morbidity and mortality, and increasing adiposity levels globally may be contributing to this. Purpose: To investigate associations of total and regional adiposity with bone mineral density (BMD) among a multi-ethnic cohort of postmenopausal women. Methods: Dual X-ray absorptiometry (DXA) imaging was undertaken for 1990 postmenopausal women without prior chronic diseases (30% Malay, 53% Chinese, and 17% Indian) from The Malaysian Cohort (TMC). The strength of the associations between standardized total and regional body fat percentages with total and regional BMD was examined using linear regression models adjusted for age, height, lean mass, ethnicity, education, and diabetes. Effect modification was assessed for ethnicity. Results: Women with a higher total body fat percentage were more likely to be Indian or Malay. Mean (SD) BMD for the whole-body total, lumbar spine, leg, and arm were 1.08 (0.11), 0.96 (0.15), 2.21 (0.22), and 1.36 (0.12) g/cm2, respectively. Total body and visceral fat percentage were inversely associated with total BMD (− 0.02 [95% CI − 0.03, − 0.01] and − 0.01 [− 0.02, − 0.006] g/cm2 per 1 SD, respectively). In contrast, subcutaneous and gynoid fat percentages were positively associated with BMD (0.007 [0.002, 0.01] and 0.01 [0.006, 0.02] g/cm2, respectively). Total body fat percentage showed a weak positive association with lumbar BMD (0.01 [0.004, 0.02]) and inverse associations with leg (− 0.04 [− 0.06, − 0.03]) and arm (− 0.02 [− 0.03, − 0.02]) BMD in the highest four quintiles. There was no effect modification by ethnicity (phetero > 0.05). Conclusion: Total adiposity was inversely associated with total BMD, although regional associations varied. There was no heterogeneity across ethnic groups suggesting adiposity may be a risk factor for low BMD across diverse populations. [ABSTRACT FROM AUTHOR]

Relative Energy Deficiency in Sport (REDs) is a syndrome describing the relationship between prolonged and/or severe low energy availability and negative health and performance outcomes. The high energy expenditures incurred during training and competition put endurance athletes at risk of REDs. The objective of this study was to investigate differences in bone quality in winter endurance athletes classified as either low-risk versus at-risk for REDs. Forty-four participants were recruited (M = 18; F = 26). Bone quality was assessed at the distal radius and tibia using high resolution peripheral quantitative computed tomography (HR-pQCT), and at the hip and spine using dual X-ray absorptiometry (DXA). Finite element analysis was used to estimate bone strength. Participants were grouped using modified criteria from the REDs Clinical Assessment Tool Version 1. Fourteen participants (M = 3; F = 11), were classified as at-risk of REDs (≥ 3 risk factors). Measured with HR-pQCT, cortical bone area (radius) and bone strength (radius and tibia) were 6.8%, 13.1% and 10.3% lower (p = 0.025, p = 0.033, p = 0.027) respectively, in at-risk compared with low-risk participants. Using DXA, femoral neck areal bone density was 9.4% lower in at-risk compared with low-risk participants (p = 0.005). At-risk male participants had 21.9% lower femoral neck areal bone density (via DXA) than low-risk males (p = 0.020) with no significant differences in females. Overall, 33.3% of athletes were at-risk for REDs and had lower bone quality than those at low-risk. [ABSTRACT FROM AUTHOR]

Trabecular microarchitecture contributes to bone strength, but its role in bone stress injury (BSI) risk in young healthy adults is unclear. Tibial volumetric BMD (vBMD), geometry, and microarchitecture, whole-body areal BMD, lean and fat mass, biochemical markers of bone metabolism, aerobic fitness, and muscle strength and power were measured in 201 British Army male infantry recruits (age 20.7 [4.3] years, BMI 24.0 ± 2.7 kg·m2) in week one of basic training. Tibial scans were performed at the ultra-distal site, 22.5 mm from the distal endplate of the non-dominant leg using High Resolution Peripheral Quantitative Computed Tomography (XtremeCT, Scanco Medical AG, Switzerland). Binary logistic regression analysis was performed to identify associations with lower body BSI confirmed by MRI. 20 recruits (10.0%) were diagnosed with a lower body BSI. Pre-injured participants had lower cortical area, stiffness and estimated failure load (p = 0.029, 0.012 and 0.011 respectively) but tibial vBMD, geometry, and microarchitecture were not associated with BSI incidence when controlling for age, total body mass, lean body mass, height, total 25(OH)D, 2.4-km run time, peak power output and maximum dynamic lift strength. Infantry Regiment (OR 9.3 [95%CI, 2.6, 33.4]) Parachute versus Line Infantry, (p ≤ 0.001) and 2.4-km best effort run time (1.06 [95%CI, 1.02, 1.10], p < 0.033) were significant predictors. Intrinsic risk factors, including ultradistal tibial density, geometry, and microarchitecture, were not associated with lower body BSI during arduous infantry training. The ninefold increased risk of BSI in the Parachute Regiment compared with Line Infantry suggests that injury propensity is primarily a function of training load and risk factors are population-specific. [ABSTRACT FROM AUTHOR]

Purpose: Electrocardiogram (ECG) QRS voltages correlate poorly with left ventricular mass (LVM). Body composition explains some of the QRS voltage variability. The relation between QRS voltages, LVM and body composition in endurance athletes is unknown. Methods: Elite endurance athletes from the Pro@Heart trial were evaluated with 12-lead ECG for Cornell and Sokolow-Lyon voltage and product. Cardiac magnetic resonance imaging assessed LVM. Dual energy x-ray absorptiometry assessed fat mass (FM) and lean mass of the trunk and whole body (LBM). The determinants of QRS voltages and LVM were identified by multivariable linear regression. Models combining ECG, demographics, DEXA and exercise capacity to predict LVM were developed. Results: In 122 athletes (19 years, 71.3% male) LVM was a determinant of the Sokolow-Lyon voltage and product (β = 0.334 and 0.477, p < 0.001) but not of the Cornell criteria. FM of the trunk (β = − 0.186 and − 0.180, p < 0.05) negatively influenced the Cornell voltage and product but not the Sokolow-Lyon criteria. DEXA marginally improved the prediction of LVM by ECG (r = 0.773 vs 0.510, p < 0.001; RMSE = 18.9 ± 13.8 vs 25.5 ± 18.7 g, p > 0.05) with LBM as the strongest predictor (β = 0.664, p < 0.001). DEXA did not improve the prediction of LVM by ECG and demographics combined and LVM was best predicted by including VO2max (r = 0.845, RMSE = 15.9 ± 11.6 g). Conclusion: LVM correlates poorly with QRS voltages with adipose tissue as a minor determinant in elite endurance athletes. LBM is the strongest single predictor of LVM but only marginally improves LVM prediction beyond ECG variables. In endurance athletes, LVM is best predicted by combining ECG, demographics and VO2max. [ABSTRACT FROM AUTHOR]

Objective: Our study's purpose was to determine the most reliable Hounsfield unit (HU) measurement method to reflect bone mineral density (BMD) on cervical spine computed tomography (CT) and to identify any factors that influence these results.Materials and Methods: We retrospectively analyzed 439 consecutive patients with mild head and neck injuries. Mean HU values of the C2-C7 vertebra were determined on each sagittal, coronal, and axial CT image. Correlation patterns were analyzed between the HU value and corresponding dual-energy X-ray absorptiometry (DXA) in the lumbar vertebra (T-score) and femoral neck (T-score). A sub-group analysis was performed according to patient age, sex, and degree of spinal degeneration.Results: The correlation coefficients for HU and DXA ranged from 0.52 to 0.65 in all cervical segments. A simple linear regression analysis revealed the following formula: T-score = 0.01 × (HU) - 4.55. The mean HU values for osteopenia and osteoporosis were 284.0 ± 63.3 and 231.5 ± 52.8, respectively. The ROC curve indicated that the HU method has a sensitivity of 89.2% and specificity of 88.7% to diagnose osteoporosis. The HU measurement showed a high correlation value (range: r = 0.64-0.70) with spine DXA score regardless of the degree of degeneration or patient age or sex.Conclusion: HU values using the upper two cervical vertebrae (C2 and C3) reflected a more reliable BMD level than other segments. Additionally, the HU of cervical CT provided reliable information regardless of measurement plane, age or sex, and degree of degeneration. [ABSTRACT FROM AUTHOR]

The accurate age at death assessment of unidentified adult skeletal individuals is a critical research task in forensic anthropology, being a key feature for the determination of biological profiles of individual skeletal remains. We have previously shown that the age-related decrease of bone mineral density (BMD) in the proximal femur could be used to assess age at death in women (Navega et al., J Forensic Sci 63:497–503, 2018). The present study aims to generate models for age estimation in both sexes through bone densitometry of the femur and radiogrammetry of the second metacarpal. The training sample comprised 224 adults (120 females, 104 males) from the "Coimbra Identified Skeletal Collection," and different models were generated through least squares regression and general regression neural networks (GRNN). The models were operationalized in a user-friendly online interface at https://osteomics.com/DXAGE2/. The mean absolute difference between the known and estimated age at death ranges from 9.39 to 13.18 years among women and from 10.33 to 15.76 among men with the least squares regression models. For the GRNN models, the mean absolute difference between documented and projected age ranges from 8.44 to 12.58 years in women and from 10.56 to 16.18 years in men. DXAGE 2.0 enables age estimation in incomplete and/or fragmentary skeletal remains, using alternative skeletal regions, with reliable results. [ABSTRACT FROM AUTHOR]

The comprehension of trabecular bone damage processes could be a crucial hint for understanding how bone damage starts and propagates. Currently, different approaches to bone damage identification could be followed. Clinical approaches start from dual X-ray absorptiometry (DXA) technique that can evaluate bone mineral density (BMD), an indirect indicator of fracture risk. DXA is, in fact, a two-dimensional technology, and BMD alone is not able to predict the effective risk of fractures. First attempts in overcoming this issue have been performed with finite element (FE) methods, combined with the use of three-dimensional high-resolution micro-computed tomographic images. The purpose of this work is to evaluate damage initiation and propagation in trabecular vertebral porcine samples using 2D linear-elastic FE models from DXA images and 3D linear FE models from micro-CT images. Results show that computed values of strains with 2D and 3D approaches (e.g., the minimum principal strain) are of the same order of magnitude. 2D DXA-based models still remain a powerful tool for a preliminary screening of trabecular regions that are prone to fracture, while from 3D micro-CT-based models, it is possible to reach details that permit the localization of the most strained trabecula. [ABSTRACT FROM AUTHOR]

Purpose of Review: The purpose of this review is to inform researchers and clinicians with the most recent imaging techniques that are employed (1) to opportunistically screen for osteoporosis and (2) to provide a better understanding into the disease etiology of osteoporosis. Recent Findings: Phantomless calibration techniques for computed tomography (CT) may pave the way for better opportunistic osteoporosis screening and the retroactive analysis of imaging data. Additionally, hardware advances are enabling new applications of dual-energy CT and cone-beam CT to the study of bone. Advances in MRI sequences are also improving imaging evaluation of bone properties. Finally, the application of image registration techniques is enabling new uses of imaging to investigate soft tissue-bone interactions as well as bone turnover. Summary: While DXA remains the most prominent imaging tool for osteoporosis diagnosis, new imaging techniques are becoming more widely available and providing additional information to inform clinical decision-making. [ABSTRACT FROM AUTHOR]

Purpose: Uncemented stems in primary total hip replacement (THR) are concerning in the elderly due to ectatic femoral canals and cortical thinning resulting in higher incidence of fracture and subsidence in this population. To obviate this concern, the authors developed a technique using autologous impaction bone grafting to achieve a better fitting femoral stem. The aim of this randomised clinical trial was to assess the efficacy of the technique.Methods: From 2013 to 2015, a total of 98 consecutive participants (100 primary THR procedures) were inducted into a single-institution, single-blinded, randomised clinical trial assessing, with radiostereometric analysis (RSA), the efficacy of autologous impaction bone grafting in uncemented primary THR compared with traditional uncemented primary THR technique. The primary outcome measure was femoral component migration using RSA. Secondary outcomes were post-operative proximal femoral bone density (using DEXA), hip function and quality of life using Oxford Hip Score (OHS) and Short Form-12 Health Survey (SF-12), hip pain and patient satisfaction.Results: There was no difference in femoral component stability (p > 0.5) or calcar resorption between the Graft and No Graft Groups at two years. There was also no difference in OHS, SF-12, pain or satisfaction between the Graft and No Graft Groups at two years (p > 0.39).Conclusions: Autologous impaction bone grafting in uncemented primary THR has shown its short-term post-operative outcomes to be equivalent to standard uncemented technique, whilst offering a better fit in patients who are between femoral stem sizes.Australian Clinical Trial Registration Number: ACTRN12618000652279. [ABSTRACT FROM AUTHOR]

This study has been undertaken in order to describe the bone mass distribution of the dry human radius via dual x-ray absorptiometry (DXA) with a Norland XR-800 densitometer machine. A sample of 39 dry radius bones was used. Two projections were made: antero-posterior and lateral, and five regions of interest were selected. The bone densities and the bone mineral contents of the various regions of the radius in the two projections were compared using Student's t tests for paired samples, with statistically significant differences being found in all of the values, except in the proximal extremity (P Ext). The area of greatest bone mineral content (BMC) was the medial diaphysis (M Diaph), followed by the distal extremity (D Ext), with the lowest value being found in the proximal extremity (P Ext). As for bone mineral density (BMD), a great symmetry is observed if we take the mean point of the longitudinal axis as a reference, with it being distributed from highest to lowest from the central part to the extremities. A correlation study of the BMD and BMC values between the segments themselves and with the total, in both positions, provides us with a high correlation (p ≤ 0.01), with the highest correlation value being found for the proximal diaphysis (P Diaph) region, indicating the heterogeneous nature of the distribution of the radius bone mass. Bone densitometry via DXA is useful in order to establish an overview of the structural construction of the human radius. [ABSTRACT FROM AUTHOR]

Objectives: To study bone mineral density (BMD) and standard serum biochemical indices among newly diagnosed and already diagnosed cases of Celiac Disease (CD) on gluten free diet for at least one year.Methods: This hospital based analytic, observational study was done at a tertiary care centre, from April 2013 through June 2014. Thirty six children (20 females) with untreated CD at diagnosis (Group A) and 36 age and sex matched children on gluten-free diet for at least one year (Group B) were studied. Serum measurements of biochemical bone health indices and BMD, assessed by dual X-ray absorptiometry, were obtained.Results: BMD Z-score was significantly low in newly diagnosed celiac patients. Patients on gluten free diet had higher BMD Z-score as compared to newly diagnosed patients (-2.02 vs. -0.65 respectively, p < 0.001). BMD Z-score was high in GI symptom patients as compared to non-GI symptom patients (-0.46+/-0.89 vs. - 0.88 = +/-0.94) in Group B. In female patients BMD Z-score was comparatively low as compared to male patients in both groups but difference was not significant. In Group A the mean serum calcium level was lower than the patients in Group B (8.72 + 0.73 vs. 9.34 + 0.65, p < 0.001). S. calcium levels were not correlated with bone mineral density (BMD) in both groups (P value >0.05).Conclusions: Children with CD are at risk for reduced BMD. Strict gluten-free diet significantly improves bone mineralization. Early diagnosis and treatment of celiac disease during childhood may protect CD patients from osteoporosis. [ABSTRACT FROM AUTHOR]

Objectives To define the prevalence of unsuspected vertebral fracture in older women undergoing screening dual X-ray absorptiometry (DXA) using vertebral fracture assessment (VFA), to assess the impact of VFA on patient management by providing additional information to BMD and FRAX ® , and to assess the agreement between VFA and standard lateral spine radiography. Materials and methods The IRB approved the study protocol. Medical records and VFA images of consecutive women aged ≥ 60 years referred for screening DXA during August 2009 to July 2010 were retrospectively reviewed. Those with known conditions potentially affecting bone metabolism or severe scoliosis were excluded. The fracture risk was estimated using FRAX ® . An agreement on the presence and type of vertebral fracture was conducted on a subset of 30 subjects. Results Of 634 eligible women, unsuspected vertebral fractures were identified in 153, resulting in an overall prevalence (95% confidence interval [CI]) of 24.1% (20.8–27.6%) and 17.4% (20.8–27.6%) for fractures of any grade and of grade 2–3, respectively. Among non-osteoporotic, low-risk women, the detection of vertebral fracture changed the diagnosis in 17.3% and treatment in 11.1%, demonstrating the impact of VFA. The agreements between VFA and radiography for T11-L4 vertebrae were 0.64–1. Conclusions The prevalence of unsuspected vertebral fracture as defined by VFA was significant in women aged ≥ 60 years referred for screening DXA. By showing vertebral fractures in low-risk non-osteoporotic subjects, VFA appeared to have clinical impact. Its agreement with radiographs for the detection of vertebral fracture was moderate to good. [ABSTRACT FROM AUTHOR]

Summary: This study assessed distal femur and lumbar spine bone mineral density (BMD) Z-scores in children with cerebral palsy. BMD z-score was lower in non-ambulatory than in ambulatory children. Somewhat surprisingly, among ambulatory children, those with better walking abilities had higher BMD z-score than those with more impaired walking ability. Introduction: Children with cerebral palsy (CP) have increased risk for low bone mineral density (BMD). The aim was to explore the difference in BMD at the distal femur and lumbar spine between ambulatory and non-ambulatory children with CP and the relationship between vitamin D status and BMD. Methods: Fifty-one children (age range 8-18 years; 20 girls) with CP participated. Their BMD Z-scores were measured in the lumbar spine and the distal femur using dual X-ray absorptiometry, and 25-hydroxy-vitamin D (25-OHD) concentrations were measured in serum. Children with GMFCS level I-III were defined as 'walkers' while children with level IV-V were defined as 'non-walkers. Results: Non-walkers had lower mean BMD Z-scores (range −1.7 to −5.4) than walkers at all sites (range −0.8 to −1.5). Among walkers, BMD Z-scores at the distal femur were lower in those with GMFCS level II than with level I ( p values < 0.004). A similar difference was found between the affected and unaffected limb in children with hemiplegia. Mean 25-OHD concentration was 45 nmol/L (SD = 18); lower in walkers (mean = 41 nmol/L; SD = 18) than in non-walkers (mean = 53 nmol/L; SD = 19; p = 0.041). There were no correlations between 25-OHD and BMD z-scores. Conclusions: The main predictor of low BMD Z-scores in the distal femur was the inability to walk, but the results suggest that the degree of the neuromotor impairment may also be a significant predictor. Vitamin D status did not correlate with BMD z-scores. [ABSTRACT FROM AUTHOR]

Objective: To evaluate bone mineral density using dual X-ray absorptiometry in Juvenile Idiopathic Arthritis (JIA) patients and factors affecting it, if any. Methods: A cross sectional study was conducted by enrolling thirty five patients of JIA and age and sex matched controls. Bone Mineral Density (BMD) and Z score of whole body, total body less head, lumbar spine and distal radius were obtained and adjusted for age, sex, weight and BMI in both cases and controls. Dietary intake of calcium, vitamin D intake, sunlight exposure, weight bearing physical activity, age of onset, duration of disease, disease activity score and treatment received (prednisolone and methotrexate) were recorded. Results: BMD was significantly lower among patients as compared to controls. Decreased dietary intake of vitamin D and calcium, decreased weight bearing physical activity and sunlight exposure were the major factors for low BMD. Use of steroid also decreased BMD to some extent, whereas use of methotrexate, disease duration and severity did not have a significant correlation with BMD. Conclusions: Apart from disease control, it is important to improve the dietary intake of calcium, vitamin D and encourage more physical activities and exposure to sunlight in JIA patients. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the value of dual X-ray absorptiometry (DXA) in comparison to non contrast computed tomography (NCCT) density as possible predictors of upper urinary tract stone disintegration by shock wave lithotripsy (SWL). This study included 100 consecutive patients, with solitary renal stone 0.5–2 cm or upper ureteral stone up to 1 cm. DXA to calculate stone mineral density (SMD) and stone mineral content (SMC) was done. NCCT was performed to measure Hounsfield units (HU). SWL was performed with an electromagnetic lithotripsy, plain X-ray documented disintegration after SWL. Successful treatment was defined as stone free or complete fragmentation after 1 or 2 sessions of SWL. The impact of patients age, sex, body mass index, stone laterality, location, volume, length, mean SMC and SMD, HU and Hounsfield density (HD), skin to stone distance (SSD) and number of shock waves were evaluated by univariate and multivariate analysis. Only 76 patients were available for follow-up. Success of disintegration was observed in 50 out of 76 patients (65.8 %). On multivariate analysis, SMC and number of shock wave were the significant independent factors affecting SWL outcome ( p = 0.04 and p = 0.000, respectively). SMC as detected by DXA is a significant predictor of success of stone disintegration by SWL. SMC measured by DXA is more accurate than HU measured by CT. Patients with high stone mineral content (SMC greater than 0.65 g) should be directly offered another treatment option. [ABSTRACT FROM AUTHOR]

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Objective: To investigate the lumbar spinal morphology in patients with and without osteoporosis by comparing the endplate changes, intervertebral disc changes, and vertebral heights. Design: This is a retrospective study. Medical records of the 3,530 patients admitted to the Physical Medicine and Rehabilitation outpatient clinics with low back pain between August 2010 and August 2011 were retrospectively reviewed. A total of 64 patients of whom 57 were females (89.1 %) and seven were males (10.9 %) were included in the study. Participants were divided into an osteoporosis group, an osteopenia group, and a nonosteoporotic control group, according to bone mineral densities. Results: In this study, mid heights of L3, L4, and L5 vertebrae were found to be higher in the normal group than in both the osteopenic and osteoporotic groups. Mid part heights of L1-2, L2-3, and L5-S1 intervertebral discs were significantly lower in the normal group when compared to the osteopenic and osteoporotic groups. End-plate marrow abnormality was detected in L1 lower end plate in 75 % of normal subjects, 40.6 % of osteopenics, and 25 % of osteoporotics. Statistically significant difference in the presence of Schmorl nodes in L5 vertebra lower end plates was present between groups; 58.3 % of normals, 34.4 % of osteopenics and 15 % of osteoporotics had Schmorl nodes in L5 vertebra lower end plates. There was a significant difference regarding disc degeneration and intradiscal gas presence in L5-S1 intervertebral discs between groups; 66.7 % of normals, 28.1 % of osteopenics, and 25 % of osteoporotics had severe disc degeneration and intradiscal gas was present in L5-S1 intervertebral discs. Conclusions: Significant changes in morphology of the lumbar spine and intervertebral discs were found. It was revealed that the effects of osteoporosis are not limited to the bone but also present in the intervertebral discs. Mid heights of intervertebral discs were higher in the osteoporotic and osteopenic groups when compared to normal subjects along with the lowered mid heights of lumbar vertebrae. It was also observed that stronger vertebral bones were associated with more disc and vertebral degeneration. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the bone mineral density (BMD) in familial Mediterranean fever (FMF) and to search the effects of genetic factors, family history of FMF and types of clinical attacks on BMD. Forty-four attack-free patients with FMF and 36 healthy voluntary subjects were included in the study. BMD measurements of lumbar spine and left proximal femur were performed by dual energy X-ray absorptiometry (DEXA). There was no statistically significant difference between patient and control groups regarding median values of lumbar BMD ( P = 0.06), lumbar T ( P = 0.08) and Z ( P = 0.12) scores, femoral neck BMD ( P = 0.13), femoral T ( P = 0.22) and Z ( P = 0.16) scores and total femur BMD ( P = 0.14), T ( P = 0.19) and Z ( P = 0.27) scores. Patients with negative FMF family history had significantly lower femoral neck BMD ( P = 0.018), femoral neck T ( P = 0.009) and Z ( P = 0.01) scores and total femur BMD ( P = 0.033) than patients with positive FMF family history. There was no significant difference among the groups regarding mutation characteristic and types of attacks in lumbar BMD, T and Z scores, femoral neck BMD, T and Z scores and total femur BMD, T and Z scores ( P > 0.05). We found that the bone loss of patients with FMF is not different from that of the controls. The increased bone loss in the patients with negative family history for FMF should be further investigated with larger patient groups taking into consideration of the risk factors related to family history for osteoporosis. [ABSTRACT FROM AUTHOR]

Summary: Advancing maternal age has been related to increased risk of fetal death and morbidity, as well as higher fracture risk during childhood, in the offspring. In the present study, we demonstrate that advancing maternal age is independently associated with reduced bone mass in the young adult male offspring. Introduction: In Sweden the maternal age in both primi- and multipara mothers has steadily increased during the last three decades. It has been previously reported that advancing maternal age increases the risk of fetal death, but also of morbidity in the offspring, such as chromosome abnormalities, leukemia, diabetes mellitus type 1, and schizophrenia. Whether or not maternal age influences peak bone mass has not been reported. The aim of the present study was to investigate whether a high maternal age was associated with lower peak bone mass, as measured using DXA in a large cohort of male offspring [the Gothenburg Osteoporosis and Obesity Determinants study (GOOD)]. Methods: Through the Swedish multi-generation register, we identified the mothers of 1,009 GOOD study subjects. From the Swedish medical birth register detailed information about the medical circumstances at the time of child birth were obtained, including maternal and offspring anthropometrics (birth height and weight), maternal age, and smoking habits, parity and length of pregnancy. Results: Maternal age was inversely correlated to areal BMD (aBMD) at the total body ( r =−0.07, p = 0.03) and the lumbar spine ( r =−0.09, p < 0.01). Using a linear regression model (with covariates including current physical activity, smoking, calcium intake, weight, present height and birth height, total body lean and fat mass in the offspring, and length of pregnancy), we found that maternal age negatively independently predicted lumbar spine aBMD ( β =−0.08, p < 0.01) in the male offspring. Conclusions: In conclusion, our results suggest that advancing maternal age could negatively affect bone mass in young adult men. [ABSTRACT FROM AUTHOR]

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Introduction: Periprosthetic bone remodelling after total hip replacement may contribute to aseptic loosening of the prosthesis. The selection between cemented and uncemented fixation of the stem is mainly determined by patient's age, general constitution and CT scan-estimated bone quality; intra-operative observation may ultimately influence the choice of the fixation method. The influence of cemented versus uncemented stem fixation on periprosthetic bone remodelling around the uncemented cup has, to our knowledge, never been studied until now. Methods: A total of 75 patients received intra-operatively manufactured stem prostheses and a standard hydroxy apatite-coated pinnacle cup. The pre-operative CT scans provides guidance for the bone quality and hence the type of stem fixation: cemented or uncemented. The influence of either type of stem fixation on periprosthetic bone remodelling around the cup and the stem was measured by bone mineral density at 6 weeks, and 3, 6 and 12 months after surgery. Results: Early changes in bone mineral density were noted. The type of stem fixation had an influence on the bone remodelling of the femur and also of the pelvis. The caudal part of the acetabulum was subject to a greater loss in BMD at 12 months in the group with cemented stem fixation. Changes at 12 months correlated with the changes measured at any time point. Conclusions: The selection of the stem implant and its type of fixation in the femoral cavity (cemented or uncemented fixation) seems to have an impact on the bone mineral density of the acetabulum. Long-term clinical follow-up is required to draw conclusions regarding the influence on prosthesis survival. [ABSTRACT FROM AUTHOR]

Summary: In this large population-based study, walking was assessed twice yearly for a week, each time by pedometer, had consistent clinically important associations with hip areal bone mineral density (aBMD) in both sexes which appears most important in those over 65 years of age suggesting that walking becomes more important with increasing age. Introduction: Walking is advocated as a preventative strategy for osteoporosis but the evidence is conflicting in females and lacking in males. The aim of this population-based longitudinal study in community dwelling older people ( n = 875) was to determine the association between pedometer determined ambulatory activity (PAA) and bone mass. Methods: Bone mass was assessed as aBMD at the hip and spine using dual X-ray absorptiometry. Steps per day were measured using pedometers for 1 week on four occasions at least 6 months apart. Data were analysed using linear mixed models. Results: At baseline, PAA was positively associated with hip aBMD. An age interaction was present with steps having a stronger association for those aged over 65 years. Longitudinally, the effect of steps on hip aBMD was constant, but not additive over time. For those over 65 years, the difference in hip aBMD between the lowest and highest steps quartiles ranged from 3.1% to 9.4%. With regard to the spine, the relationship between daily steps and spine aBMD was modified by sex. For males; there was no significant relationship between steps and spine aBMD. However, for females, higher steps were associated with higher spine aBMD with the effect being constant over time but not additive. There was no evidence of a threshold effect. Conclusion: In conclusion, pedometer-determined ambulatory activity has consistent clinically important associations with hip aBMD in both sexes which appears most important in those over 65 years of age. The associations for spine aBMD were both weaker and inconsistent suggesting site specificity. [ABSTRACT FROM AUTHOR]

Summary: This study for the first time investigates the association of bone mineral density (BMD) with angiographically determined coronary atherosclerosis in men. Our data show that the prevalence of low BMD is very high in men undergoing coronary angiography. However, neither osteopenia nor osteoporosis is associated with an increased prevalence of angiographically determined coronary atherosclerosis. Introduction: The association of low BMD with angiographically determined coronary atherosclerosis in men is unknown. Methods: We enrolled 623 consecutive men undergoing coronary angiography for the evaluation of established or suspected coronary artery disease (CAD). BMD was assessed by dual X-ray absorptiometry. CAD was diagnosed in the presence of any coronary artery lumen narrowing at angiography; coronary stenoses with lumen narrowing ≥50% were considered significant. Results: From the total study cohort (mean age of 64 ± 11 years), 207 patients (33.2%) had osteopenia and 65 (10.4%) had osteoporosis; at angiography, CAD was diagnosed in 558 patients (89.6%) and 403 (64.7%) had significant coronary stenoses. In multivariate logistic regression analysis neither osteopenia nor osteoporosis was associated with an increased prevalence of CAD (adjusted odds ratios (ORs) = 0.71 [95% confidence interval 0.40–1.23]; p = 0.222 and 1.03 [0.38–2.80]; p = 0.955, respectively) or with significant coronary stenoses (OR 0.74 [0.52–1.07], p = 0.112 and 0.72 [0.41–1.26]; p = 0.251, respectively). Also, as a continuous variable, BMD was not associated with angiographically diagnosed CAD. Conclusions: The prevalence of low BMD is very high in men undergoing coronary angiography. However, low BMD is not associated with angiographically determined coronary atherosclerosis in men. [ABSTRACT FROM AUTHOR]

The utility of vertebral fracture assessment (VFA) by DXA to detect prevalent vertebral fracture in a multicenter setting was investigated by comparison to conventional radiography. While limited by lower image quality, overall performance of VFA was good but had a tendency to miss mild prevalent fractures. In osteoporosis clinical trials standardized spine radiographs are used to detect vertebral fractures as a study endpoint. Lateral spine imaging with dual X-ray absorptiometry (DXA) scanners, known as vertebral fracture assessment (VFA) by DXA, presents a potential alternative to conventional radiography with lower radiation dose and greater patient convenience. We investigated in a multicenter setting the ability of VFA to detect fractures in comparison with conventional radiography. The study examined 203 postmenopausal women who had imaging of the spine by DXA and radiography. Three radiologists experienced in vertebral fracture assessment independently read the VFA scans and radiographs using the Genant semiquantitative method on two occasions. Analyzing the data from all readable vertebrae, the kappa statistic, sensitivity, and specificity ranged from 0.64–0.77, 0.65–0.84, and 0.97–0.98, respectively. Considering only moderate and severe fractures improved the kappa statistic (0.80–0.91) and sensitivity (0.70–0.86). While image quality of VFA is inferior to radiography, the detection of vertebral fractures using visual scoring is feasible. However, VFA underperformed due to unreadable vertebrae and reduced sensitivity for mild fractures. Nevertheless, VFA correctly identified most moderate and severe vertebral fractures. Despite this limitation, VFA by DXA provides an important tool for clinical research. [ABSTRACT FROM AUTHOR]

In this study adaptations in body composition, physical fitness and metabolic health were examined during 21 weeks of endurance and/or strength training in 39- to 64-year-old healthy women. Subjects (n = 62) were randomized into endurance training (E), strength training (S), combined strength and endurance training (SE), or control groups (C). S and E trained 2 and SE 2 + 2 times in a week. Muscle strength and maximal oxygen uptake (VO(2)max) were measured. Leg extension strength increased 9 +/- 8% in S (P < 0.001), 12 +/- 8% in SE (P < 0.001) and 3 +/- 4% in E (P = 0.036), and isometric bench press 20% only in both S and SE (P < 0.001). VO(2)max increased 23 +/- 18% in E and 16 +/- 12% in SE (both P < 0.001). The changes in the total body fat (dual X-ray absorptiometry) did not differ between groups, but significant decreases were observed in E (-5.9%, P = 0.022) and SE (-4.8%, P = 0.005). Lean mass of the legs increased 2.2-2.9% (P = 0.004-0.010) in S, SE and E. There were no differences between the groups in the changes in blood lipids, blood pressure or serum glucose and insulin. Total cholesterol and low-density lipoprotein cholesterol decreased and high-density lipoprotein cholesterol increased in E. Both S and SE showed small decreases in serum fasting insulin. Both endurance and strength training and their combination led to expected training-specific improvements in physical fitness, without interference in fitness or muscle mass development. All training methods led to increases in lean body mass, but decreases in body fat and modest improvements in metabolic risk factors were more evident with aerobic training than strength training. [ABSTRACT FROM AUTHOR]

Osteoporosis is a multifactorial disorder that requires advanced diagnostic evaluation tools. It should not be considered to be an inevitable disease entity or as a logical consequence of the physiological ageing process. Osteoporosis can be diagnosed and – more importantly – properly treated. It is therefore incomprehensible that most of the patients with diagnosed osteoporosis do not receive a specific pharmacotherapeutic treatment. Since orthopedic trauma surgeons most often see a patient with an osteoporosis-associated fracture on a first-hand basis, they, after providing adequate treatment of the fracture, must play a key role in initiating the primary diagnostics and therapy according to national or international guidelines for patients with previous osteoporotic fractures. Treatment should be closely coordinated with general practitioners so that a continuation of the therapy initiated in the hospital can be guaranteed. Basic measures for fracture prevention, including dietary supplements of calcium and vitamin D, should be recommended and implemented for all patients, whereas only those patients with the diagnosis of a manifest osteoporosis should receive a specific pharmacotherapy. Antiresorptive and anabolic drugs that are licensed for the treatment of men or postmenopausal women with osteoporosis have been shown to effectively reduce the incidence of vertebral and non-vertebral fractures. An evaluation of the treatment efficiency should also be performed, such as routine clinical re-evaluation and the measuring of the bone mineral density by dual X-ray absortiometry, every 18–24 months after the initiation of the pharmacotherapy. [ABSTRACT FROM AUTHOR]

Unlabelled: Multiple skinfold anthropometry (MSA) and bioelectrical impedance analysis (BIA) are useful as clinically non-invasive, inexpensive and portable techniques, although it is not clear if they can be used interchangeably in the same patient to routinely assess her/his body composition. In order to compare BIA, MSA and DXA in the estimation of lean body mass (LBM) of a pediatric obese population, 103 obese [body mass index (BMI) > 97th percentile] children (median age: 11 years; range: 5.4-16.7 years) underwent nutritional evaluation. After an overnight fast, the subjects' anthropometric measurements were performed by the same investigator: body weight (BW), height, skinfold thickness (four sites); fat body mass (FBM) using Brook or Durnin equations and dual X-ray absorptiometry (DXA). BIA was performed using a bioelectrical impedance analyzer (Analicor-Eugedia, 50 kHz) and Houtkooper's equation to calculate LBM. Linear regression analysis was performed to evaluate the relationship between the prediction of LBM by MSA, DXA and BIA. The differences between the three techniques were analysed using Student's t-test for paired observations and the Bland and Altmann method. A considerable lack of agreement was observed between DXA- and BIA-LBM (delta = -4.37 kg LBM; delta-2sigma = -11.6 kg LBM; delta+2sigma = +2.8 kg LBM); between DXA- and MSA-LBM (delta = -1.72 kg LBM; delta-2sigma = -8.2 kg LBM; delta+2sigma = +4.8 kg LBM) and between BIA- and MSA-LBM (delta = -2.65 kg LBM; delta-2sigma = -10.5 kg LBM; delta+2sigma = +5.2 kg LBM).Conclusion: In obese children, DXA, BIA and MSA should not be used interchangeably in the assessment of LBM because of an unacceptable lack of agreement between them. The discrepancies between methods increase with the degree of obesity. [ABSTRACT FROM AUTHOR]

Objective:To identify the proportion of weight lost as fat-free mass (FFM) by various weight loss interventions.Methods:Medline and Embase were systematically searched for reliable measurements of FFM before and after weight loss of >10 kg and eligible data were pooled. In a fixed effect model of % FFM loss/weight loss (%FFML), linear regression analysis was used to determine the influence of degree of caloric restriction, exercise, magnitude of weight loss, initial body mass index (BMI) and type of surgery.Results:Data were included from 26 cohorts treated with dietary and behavioral interventions and 29 cohorts of bariatric surgery patients. The degree of caloric restriction was positively associated with %FFML (r 2=0.31, P=0.006) and in three randomized controlled trials exercise was shown to decrease %FFML. Compared with laparoscopic adjustable gastric banding (LAGB), biliopancreatic diversion (BPD) and roux en Y gastric bypass (RYGB) caused greater loge (natural log) %FFML (r 2=0.453, P<0.001). Differences in loge %FFML between surgical procedures were independent of initial BMI and magnitude of weight loss.Conclusions:The degree of caloric restriction, exercise and rate of weight loss influence the proportion of weight lost as FFM after non-surgical interventions. For surgical interventions, BPD and RYGB result in greater %FFML than LAGB.International Journal of Obesity (2007) 31, 743–750. doi:10.1038/sj.ijo.0803483; published online 31 October 2006 [ABSTRACT FROM AUTHOR]

Introduction: Previous studies suggesting different effects of diet on post-menopausal bone loss may have given conflicting results because they sometimes failed to exclude confounding conditions or used imprecise methodology. Design: To identify dietary determinants of bone loss from the lumbar spine after menopause in women not taking hormone replacement who developed no evidence of spondylotic or sclerotic degenerative disease, forty-three women were followed with repeated (mean = 12) measurements of bone mineral density (BMD) at L2-4 for 11–14 years. Eleven developed evidence suggestive of degenerative disease and were excluded. Diet was assessed at the beginning of the study and 2.5 years later using 3-day and 7-day periods of weighed intakes. Nutrients estimated were: carbohydrate, fat, protein, fibre, calcium, magnesium, iron, phosphorus, copper, zinc and six vitamins. We tested the ability of diet to predict post-menopausal bone loss using stepwise regression. Results: Each woman's BMD change was described by a single coefficient after log transformation of the BMD data. The best model for BMD loss including dietary factors alone had two significant determinants: daily energy or protein (p=0.0003) intake was adverse, while dietary iron (p=0.002) was predictive of bone maintenance, an effect that persisted if iron was expressed as a ratio to energy intake. Adding body mass index to the model increased the goodness of fit (R²adj rose from 0.33 to 0.42) without affecting the statistical significance of the dietary determinants. Conclusions: Diet may influence bone loss after menopause, with dietary iron (or an associated factor) possibly having a protective effect on bone at the spine. [ABSTRACT FROM AUTHOR]

Objective:To evaluate whether polymorphisms in the peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PPARGC1A) gene were related to body fat in Asian Indians.Methods:Three polymorphisms of PPARGC1A gene, the Thr394Thr, Gly482Ser and +A2962G, were genotyped on 82 type 2 diabetic and 82 normal glucose tolerant (NGT) subjects randomly chosen from the Chennai Urban Rural Epidemiology Study using PCR-RFLP, and the nature of the variants were confirmed using direct sequencing. Linkage disequilibrium (LD) was estimated from the estimates of haplotypic frequencies using an expectation–maximization algorithm. Visceral, subcutaneous and total abdominal fat were measured using computed tomography, whereas dual X-ray absorptiometry was used to measure central abdominal and total body fat.Results:None of the three polymorphisms studied were in LD. The genotype (0.59 vs 0.32, P=0.001) and allele (0.30 vs 0.17, P=0.007) frequencies of Thr394Thr polymorphism were significantly higher in type 2 diabetic subjects compared to those in NGT subjects. The odds ratio for diabetes (adjusted for age, sex and body mass index) for the susceptible genotype, XA (GA+AA) of Thr394Thr polymorphism, was 2.53 (95% confidence intervals: 1.30–5.04, P=0.009). Visceral and subcutaneous fat were significantly higher in NGT subjects with XA genotype of the Thr394Thr polymorphism compared to those with GG genotype (visceral fat: XA 148.2±46.9 vs GG 106.5±51.9 cm2, P=0.001; subcutaneous fat: XA 271.8±167.1 vs GG 181.5±78.5 cm2, P=0.001). Abdominal (XA 4521.9±1749.6 vs GG 3445.2±1443.4 g, P=0.004), central abdominal (XA 1689.0±524.0 vs GG 1228.5±438.7 g, P<0.0001) and non-abdominal fat (XA 18763.8±8789.4 vs GG 13160.4±4255.3 g, P<0.0001) were also significantly higher in the NGT subjects with XA genotype compared to those with GG genotype. The Gly482Ser and +A2962G polymorphisms were not associated with any of the body fat measures.Conclusion:Among Asian Indians, the Thr394Thr (G → A) polymorphism is associated with increased total, visceral and subcutaneous body fat.International Journal of Obesity (2006) 30, 884–891. doi:10.1038/sj.ijo.0803228; published online 31 January 2006 [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the association between grip strength change and bone health according to menopausal status . A random sample of 971 pre- to postmenopausal women from the Kuopio Osteoporosis Risk Factor and Prevention (OSTPRE) study cohort was measured with dual X-ray absorptiometry in the lumbar spine (LS) and femoral neck (FN) and grip strength with pneumatic squeeze dynamometer at baseline (1989–1991), 5 years (1994–1997), and 10 years (1999–2001). Fractures were recorded based on self-reports and validated from medical records. Women were divided into two groups according to change in grip strength quartile from baseline to 5-year follow-up: not improved ( n = 735) and improved ( n = 236). In the total population, the greatest bone loss was observed in perimenopausal (beginning of menopause during follow-up, n = 311) women [ P < 0.001 vs. premenopausal women ( n = 139)], and it declined in postmenopausal ( n = 521) women [ P < 0.001 by analysis of covariance (ANCOVA)]. The perimenopausal bone loss rate was significantly lower in women in the improved group in comparison to the not improved group ( P < 0.01) in contrast to the pre- and postmenopausal groups ( P > 0.05). Accordingly, there was a greater decline in perimenopausal LS and FN T-scores in the improved group vs. the not improved group over the first 5-year follow-up interval ( P < 0.05 by ANCOVA) and remained unchanged over the 10-year follow-up. In perimenopausal women, there was a trend toward higher fracture-free survival rate in the improved group (82%) vs. the not improved group (88%) after 10 years. Adjustments did not change the results. In conclusion, maintenance of grip strength is associated with menopausal bone loss and future fractures. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the associations between grip strength change and postmenopausal bone loss. The study population, 622 peri- and postmenopausal women, was a random sample of the OSTPRE-study cohort ( n =13,100) in Kuopio, Finland. Bone mineral density (BMD) at the lumbar spine (LS) and femoral neck (FN) was measured with dual X-ray absorptiometry and grip strength with a pneumatic squeeze dynamometer at baseline in 1989–1991, at the 5-year follow-up in 1994–1997 and at the 10-year follow-up in 1999–2001. Women were divided into three groups according to the change in age-grouped grip strength quartile they belonged to in each measurement ( n in 5-year/10-year follow-up): “decreased” ( n =150/ n =140), “maintained” ( n =314/ n =320) and “improved” ( n =158/ n =162). Women within the improved group had significantly lower bone loss at both FN and LS in comparison to the other two groups after 10 years of follow-up ( P <0.01). Furthermore, in HRT non-users ( n =305) the difference between the improved group and maintained group was only modest ( P =0.04). In contrast, in HRT users ( n =310) the mean annual BMD change among the improved group was positive (bone gain 0.11%/year) and differed significantly in comparison to modest bone loss in the decreased and maintained groups in both LS and FN ( P <0.01). The linear trend between grip strength quartile change and LS/FN bone loss was significant in HRT users ( P <0.001) in contrast to HRT non-users ( P =NS) in the linear regression model. Any of these differences were not affected by adjustments for age, weight, height and other potential confounders. In conclusion, the present study suggests that improvement in age-grouped grip strength quartile is strongly associated with axial bone loss among postmenopausal women. This effect seemed to interact positively with estrogen repletion status. These results encourage performing further clinical studies on associations between muscle strength changes and bone loss. [ABSTRACT FROM AUTHOR]

Three-dimensional accurate evaluation of the geometry of the proximal femur may be helpful for hip fracture risk evaluation. The purpose of this study was to apply and validate a stereo-radiographic 3D reconstruction method of the proximal femur, using contours identification from biplanar DXA images. Twenty-five excised human proximal femurs were investigated using a standard DXA unit. Three-dimensional personalized models were reconstructed using a dedicated non-stereo corresponding contours (NSCC) algorithm. Three-dimensional CT-scan reconstructions obtained on a clinical CT-scan unit were defined as geometric references for the comparison protocol, in order to assess accuracy and reproducibility of the 3D stereo-radiographic reconstructions. The precision of a set of 3D geometric parameters (femoral-neck axis length, mid-neck cross-section area, neck-shaft angle), obtained from stereo-radiographic models was also evaluated. This study shows that the NSCC method may be applied to obtain 3D reconstruction from biplanar DXA acquisitions. Applied to the proximal femur, this method showed good accuracy as compared with high-resolution personalized CT-scan models (mean error = 0.8 mm). Moreover, precision study for the set of 3D parameters yielded coefficients of variation lower than 5%. This is the first study providing 3D geometric parameters from standard 2D DXA images using the NSCC method. It has good accuracy and reproducibility in the present study on cadaveric femurs. In vivo prospective studies are needed to evaluate its discriminating potential on hip fracture risk prediction. [ABSTRACT FROM AUTHOR]

The DMS Lexxos is the first cone-beam dual X-ray absorptiometry (DXA) system capable of performing bone mineral density (BMD) measurements of the spine and hip. By using a two-dimensional (2-D) detector array rather than the linear array used with conventional fan-beam DXA systems, image acquisition time on Lexxos is only 1.5 s. However, the need to correct for the large signal from scattered radiation reaching the detector is a potential source of error in cone-beam DXA. The aim of this clinical evaluation of the Lexxos bone densitometer was to investigate the relative accuracy of cone-beam BMD measurements compared with conventional DXA by performing anin vivocross-calibration study with an established fan-beam system, the Hologic QDR-4500. Spine (L1-L4) and hip BMD measurements were performed in 135 patients (111 women, 24 men) referred for a bone densitometry examination. Duplicate Lexxos measurements were performed in 27 female patients to evaluate precision. On average, Lexxos spine and femoral neck BMD measurements were 2% lower than those on the QDR-4500, whereas total hip BMD was 5% higher. Larger differences were found for the trochanter and Ward’s triangle regions. For all sites, Lexxos BMD measurements showed a strong linear relationship with those measured on the QDR-4500 with correlation coefficients in the ranger= 0.95 to 0.97 for the clinically important spine, femoral neck, and total hip regions. The root mean standard error (RMSE) between Lexxos and QDR-4500 BMDs ranged from 0.037 g/cm2 for the femoral neck to 0.060 g/cm2 for the spine, whereas Lexxos precision was 1.3% for total hip, 2.0% for femoral neck, and 2.3% for spine BMD. Although for the hip BMD sites the RMSE and precision of Lexxos measurements were similar to studies of pencil-beam and fan-beam DXA systems, the results for the spine were poorer than expected. The findings of this study suggest that Lexxos corrects accurately for the effects of scattered radiation at the detector, but that the precision of spine BMD measurements may be limited by involuntary patient movement between the high and low energy X-ray exposures. [ABSTRACT FROM AUTHOR]

The high precision and stable calibration of dual X-ray absorptiometry (DXA) scanners have led to their widespread use in longitudinal studies for research and the follow-up of individual patients who are receiving treatment for osteoporosis. However, difficulties in maintaining the continuity of the bone mineral density (BMD) calibration scale can arise when an old DXA system is replaced by a newer model. We report the results of an in vivo cross-calibration study performed when a GE-Lunar Prodigy fan-beam system replaced a DPX-L pencil-beam scanner. Lumbar spine and hip DXA scans were performed in 133 patients (104 female, 29 male) attending long-term BMD monitoring. On average, lumbar spine BMD measurements on the two systems agreed closely, with Prodigy values 1% lower than those on the DPX-L. However, after allowing for this difference, the root mean square error (RMSE) of 0.037 g/cm2 was larger than in previous cross-calibration studies reported in the literature, and was 3 times the value expected from the precision of the BMD measurements. Mean femoral neck BMD also agreed closely between the two systems, although for Prodigy, the spread of measurements was 10% smaller than that for the DPX-L. For the trochanter and Ward’s triangle regions, mean BMD was 4% and 6% lower, respectively, on the Prodigy system, and the results were affected by a similar compression of the range of values. RMSE values were 0.037 g/cm2, 0.044 g/cm2, and 0.044 g/cm2, respectively, for the femoral neck, trochanter, and Ward’s triangle sites. When the high value of the RMSE was investigated, it was found that for lumbar spine BMD, patient body weight and the difference between the two systems in the percentage fat reported in the soft tissue reference region explained 40% of the variance. This enabled equations to be developed that significantly improved the agreement between scans performed on the two systems. Smaller improvements were obtained for the femur BMD measurements. [ABSTRACT FROM AUTHOR]

The aims of this study were to: (a) examine differences in speed of sound (SOS) between the right (SOS(R)) and left (SOS(L)) radius; (b) detect bone loss following proximal forearm fracture by SOS measurement at the radius; and (c) compare SOS(L) and bone mineral density (BMD) of one-third, mid-distal, ultra-distal and total region of the left radius. Two hundred eighty-seven Caucasian women (mean age 60.4+/-6.7 years) participated in this study. All subjects were right-handed. Twenty-seven women (mean age 63.6+/-8.0 years) had suffered a high-energy fracture of the right or left forearm. The SOS was assessed using a quantitative ultrasound device, whereas BMD was measured by dual energy X-ray absorptiometry (DXA). The SOS(R) was significantly higher than SOS(L) (4047.5+/-121.0 vs 4026.3+/-113.4 m/s; p<0.001). The contralateral absolute difference was 1.94% (95% confidence intervals: 1.73-2.15%). In women who had suffered a fracture of their right forearm, SOS(R) was not significantly higher than SOS(L )(3989.9+/-141.8 vs 3985.0+/-151.1 m/s), whereas the bilateral difference was reduced to 1.45%. In women with a previous fracture of the left forearm, SOS(R) was significantly higher than SOS(L) (4076.9+/-92.8 vs 3992.6+/-124.0 m/s; p<0.01) and the bilateral difference was increased to 2.61%. Of the 260 subjects without fracture, 155 had greater SOS in the right radius, 102 had greater SOS in the left radius and 3 patients had equal values of SOS in both bones. Calculated correlations between SOS and BMD were weak to moderate ( r=0.27-0.41; p<0.0001 for all comparisons). The SOS measurements should be performed on both radial bones. A high-energy forearm fracture results in a decrease in SOS measured at the radius. Radial-bone SOS measurements cannot predict forearm BMD. [ABSTRACT FROM AUTHOR]

The diagnosis of osteoporosis is generally based on the assessment of bone mineral content with dual X-ray absorptiometry (DXA) but does not account for the spatial distribution and inherent material properties of the tissue. Peripheral quantitative computed tomography (pQCT) permits one to measure the compartment-specific density and geometry-based parameters of cortical bone. Quantitative ultrasound (QUS) parameters are associated with material properties of cortical bone. The purpose of this study was to test the hypothesis that pQCT and cortical QUS provide additional information to DXA in predicting structural strength of the distal radius. The intact right arm and the isolated left radius were harvested from 70 formalin-fixed cadavers (age 79±11 years). The bone mineral content (BMC) was assessed with DXA at the radial metaphysis and shaft. pQCT was also used at the metaphysis and the shaft, while QUS was employed only at the shaft. The failure loads of the radius were assessed by use of a 3-point bending test (isolated radius) and a complex fall simulation (intact arm). The BMC (DXA) displayed a correlation of r=0.96 with the failure moments in 3-point bending (P<0.001). The correlation between failure load and geometry-based parameters (pQCT) ranged from r=0.85 to r=0.96 and was r=0.64 for the speed of sound (QUS) (P <0.001). Cortical thickness (pQCT) improved the prediction marginally (r=0.964) in combination with DXA. For the fall simulation, the correlation coefficients were r=0.76 for BMC (DXA) of the shaft, r=0.83 for metaphyseal bone content (pQCT), r=0.55 for QUS, and ranged from r=0.59 to r=0.74 for geometry-based parameters at the shaft (pQCT). pQCT and QUS parameters provided no significant improvement versus DXA alone. Measurement of bone mass by DXA or pQCT thus appears to be sufficient as a surrogate of mechanical strength and fracture risk of the distal radius. [ABSTRACT FROM AUTHOR]

OBJECTIVE:: To compare the long-term compliance and effects of two low-fat diets differing in carbohydrate to protein ratio on body composition and biomarkers of cardiovascular disease risk in obese subjects with hyperinsulinemia. DESIGN:: Outpatient, parallel, clinical intervention study of two groups of subjects randomly assigned to either a standard protein (SP; 15% protein, 55% carbohydrate) or high-protein (HP; 30% protein, 40% carbohydrate) diet, during 12 weeks of energy restriction (~6.5?MJ/day) and 4 weeks of energy balance (~8.3?MJ/day). Subsequently, subjects were asked to maintain the same dietary pattern for the succeeding 52 weeks with minimal professional support. SUBJECTS:: A total of 58 obese, nondietetic subjects with hyperinsulinemia (13 males/45 females, mean age 50.2?y, mean body mass index (BMI) 34.0?kg/m2, mean fasting insulin 17.8?mU/l) participated in the study. MEASUREMENTS:: Body composition, blood pressure, blood lipids, fasting glucose, insulin, CRP and sICAM-1 were measured at baseline and at weeks 16 and 68. Urinary urea/creatinine ratio was measured at baseline, week 16 and at 3 monthly intervals thereafter. RESULTS:: In total, 43 subjects completed the study with similar dropouts in each group (P=0.76). At week 68, there was net weight loss (SP -2.9±3.6%, HP -4.1±5.8%; P<0.01) due entirely to fat loss (P<0.001) with no diet effect. Both diets significantly increased HDL cholesterol concentrations (P<0.001) and decreased fasting insulin, insulin resistance, sICAM-1 and CRP levels (P<0.05). Protein intake was significantly greater in HP during the initial 16 weeks (P<0.001), but decreased in HP and increased in SP during 52-week follow-up, with no difference between groups at week 68, indicating poor long-term dietary adherence behaviour to both dietary patterns. CONCLUSION:: Without active ongoing dietary advice, adherence to dietary intervention is poor. Nonetheless, both dietary patterns achieved net weight loss and improvements in cardiovascular risk factors.International Journal of Obesity (2004) 28, 661-670. doi:10.1038/sj.ijo.0802617 Published online 9 March 2004 [ABSTRACT FROM AUTHOR]

Dual X-ray absorptiometry (DXA), which is the most commonly used method for the diagnosis and followup of human bone health, is known to produce accurate estimates of bone mineral density (BMD). However, high costs and problems with availability may prevent its use for mass screening. The objective of the present study was to estimate BMD values for healthy persons and those with conditions known to be associated with BMD, using artificial neural networks (ANN). An ANN was used to quantitatively estimate site-specific BMD values in comparison with reference values obtained by DXA (i. e. BMDspine, BMDpelvis, and BMDtotal). Anthropometric measurements (i. e. sex, age, weight, height, body mass index, waist-to-hip ratio, and the sum of four skinfold thicknesses) were fed to the ANN as independent input variables. The estimates based on four input variables were generated as output and were generally identical to the reference values for all studied groups. We believe the ANN is a promising approach for estimating and predicting site-specific BMD values using simple anthropometric measurements. [ABSTRACT FROM AUTHOR]

The objective of the present report was to develop mathematical prediction formulae for the lumbar spine, pelvis and total bone mineral density (BMD) based on the osteoporosis risk factors age and BMI in healthy and cirrhotic postmenopausal women. The study population comprised 20 postmenopausal cirrhotic women (late PM cirrhotic women), 20 postmenopausal healthy women matched for age and BMI (late PM healthy women), and 19 younger postmenopausal healthy women matched for BMI (early PM healthy women). Segmental and total bone mineral content and BMD, total bone-free lean body mass and total fat mass were measured for all women using dual X-ray absorptiometry (DXA). The prediction formulae for late PM cirrhotic women had higher cumulative correlation coefficients (r=0.71, p=0.05 for spine BMD, r=0.84, p=0.013 for pelvis BMD, and r=0.89, p=0.004 for total BMD) than those for early PM healthy women (r=0.64, p=0.015 for spine BMD, r=0.69, p=0.002 for pelvis BMD, and r=0.62, p=0.022 for total BMD) and late PM healthy women (r=0.29, p=NS for spine BMD, r=0.39, p=NS for pelvis BMD, and r=0.54, p=NS for total BMD). The mathematical formulae based on the variables age and BMI were capable of predicting lumbar spine BMD, pelvis BMD, and total BMD by DXA for the three groups of postmenopausal women. [ABSTRACT FROM AUTHOR]

This 64-week prospective cohort trial evaluated the effects of 20-mg oestradiol implants, replaced every 4 months, in healthy postmenopausal women aged 45–65 years. Of 20 implant and 14 control subjects who remained in the trial at 32 weeks, 13 implant and seven controls continued to 64 weeks, with no baseline differences between completing and dropout subjects. At 64 weeks, implant subjects displayed increases of 5.4–7.6% in spine and hip bone mineral density (p<0.05 versus controls). The abdominal fat-to-lean soft tissue ratio decreased by 18% in implant subjects (p<0.001), but did not change in controls (p<0.05 implants versus controls). Neither group displayed significant changes in weight, %fat or appendicular skeletal muscle mass. The 32-week data were consistent with these results. Hence, oestradiol implant therapy can reduce abdominal adiposity and could lower the risk of obesityrelated metabolic disorders. [ABSTRACT FROM AUTHOR]

The distal radius is an important site for the early detection of patients at risk for fracture. Since measuring bone strength in vivo is not possible, we evaluated which bone assessment method of the forearm would best predict failure load of the distal radius and computed a factor of risk for wrist fracture (Φwrist). Thirty-eight cadaveric forearm specimens were measured by five different techniques to assess bone density, bone mineral content, geometry and trabecular structure at the distal forearm. The bone assessment techniques included dual-energy X-ray absorptiometry (DXA) of the radius, peripheral quantitative computed tomography (pQCT) of the 4% and 20% distal sites of the radius, DXA of the phalanges, digital X-ray radiogrammetry of the forearm (DXR-BMD), and quantitative ultrasound of the radius. The failure load of each excised radius was determined by simulating a fall on an outstretched hand. The pQCT measurements of polar stress-strain index and cortical content explained the greatest portion of variance in failure load (r2=0.82–0.85). Bone mineral content measures were generally better predictors of failure load (r2=0.53–0.85) than the corresponding volumetric or areal bone mineral density values (r2=0.22–0.69) measured by either pQCT or DXA. Multiple regression analysis showed that the addition of a bone geometry measure improved the ability of a bone density measure alone to predict failure load. There was high variability in the ability of different techniques and different variables within a given technique to predict failure load. Estimates of the factor of risk for wrist fracture (Φwrist) revealed that the women in this study would have been likely to fracture their distal radius upon falling from a standing height (Φwrist=1.04), whereas the men would have likely withstood the impact without fracturing their wrist (Φwrist=0.79). [ABSTRACT FROM AUTHOR]

In this study we aimed to establish the dual-energy X-ray absorptiometry (DXA) bone mineral density (BMD) reference values of healthy Turkish women and men residing in Izmir, western Turkey. We examined 347 women and 119 men (age range 20-80 years) who did not have any known risk factor that might affect bone mass. The BMD measurements were performed by Hologic QDR 4500 W Elite DXA instrument from the lumbar spine (L1-L4) and non-dominant hip. In women the mean BMD (g/cm(2))+/-standard deviation (SD) of the normal reference group between 20 and 39 years of age was 0.963+/-0.121 g/cm(2) in the lumbar spine and 0.891+/-0.119 g/cm(2) in total femoral region. The percentages of annual and total BMD losses in women between 30 and 80 years of age were 0.74 and 29% at spinal level and 0.65 and 26% in femoral region, respectively. The average BMD of the normal men's group between 20 and 39 years of age was 0.996+/-0.111 g/cm(2) in the lumbar spine and 1.025+/-0.110 g/cm(2) in femoral region. The percentages of annual and total BMD losses were 0.33 and 13% at spinal level and 0.50 and 20% in femoral region, respectively. In conclusion, like the values reported from mid-Anatolian region of Turkey, the BMD values of Turkish women and men residing in Izmir, western Anatolia, are also lower than in most European countries with regard to US and preinstalled Hologic values. [ABSTRACT FROM AUTHOR]

: The aim of the current study was to estimate the embryo/fetus radiation doses and risks associated with spinal and hip dual X-ray absorptiometry (DXA) scans performed on the pregnant mother. The results were compared with the embryo/fetus dose from a thoracolumbar radiograph and pelvic radiograph. Posteroanterior (PA) lumbar spine and proximal femur scans during the first, second and third trimesters were performed on a phantom simulating pregnancy at the three trimesters of gestation. All scans were carried out using a Hologic 1000/W pencil beam DXA unit. Moreover, embryo/fetus doses from a (a) thoracolumbar radiograph and (b) pelvic radiograph were estimated for all periods of gestation using the same phantom. Radiation doses were measured using thermoluminescent dosimeters. The dose reduction achievable by shielding the embryo/fetus with a protective apron during DXA scans was studied for all trimesters of gestation. The embryo/fetus doses during the first trimester were measured to be 1.7 mGy and 2.7 mGy for the PA spine and femur DXA scan, respectively, for an embryo/fetus located 8.5 cm from the anterior maternal surface. The risk of excess fatal cancer was 0.2 per million unborn children irradiated in utero for measurements of the spine and 0.3 per million unborn children for measurements of the femur. The embryo/fetus doses during the second and third trimesters were 2.7 mGy and 4.9 mGy respectively for the scans of the lumbar spine. The risk of childhood fatal cancer was 0.3 per million for the second trimester and 0.5 per million for the third trimester. The embryo/fetus radiation doses during the second and third trimesters were estimated as 1.4 mGy and 1.0 mGy respectively for the examinations of the proximal femur. The risk of childhood fatal cancer was 0.1 per million for both trimesters. The use of the apron resulted in a very small change in the dose absorbed by the embryo/fetus. The embryo/fetus dose associated with both DXA modes investigated in the current study is at least 700 times lower in comparison with embryo/fetus dose from a thoracolumbar or pelvic radiograph in all periods of gestation. In conclusion, the embryo/fetus dose in bone density measurements of spine and femur using pencil beam DXA is lower than the average daily natural background in the United States of 8 mGy. The health provider can decide whether a DXA scanning is beneficial to a pregnant woman, taking into account the potential radiation risks to the embryo/fetus presented in the current study. [ABSTRACT FROM AUTHOR]

The study assessed the precision, sensitivity, and specificity of a recently developed peripheral dual-energy X-ray absorptiometry (DXA) scanner, applied to the calcaneus, in the identification of individuals with osteoporosis at axial sites by DXA. Two hundred and two women, aged 55.2 ± l3.7 years (mean ± SD), participated in the study. The precisions (coefficient of variation) of measurements in vitro (0.48%) and in vivo (1.40%) were very good. The in vivo precision was independent of the operator, foot size, foot width, weight, height, and body mass index. Calcaneus BMD correlated moderately (r = 0.494–0.690, P <0.001) with axial BMD measurements by DXA. Using the World Health Organization (WHO) criterion for defining osteoporosis (T score ? -2.5) the specificity of the calcaneus to identify patients with osteoporosis at total hip, femoral neck, spine, or any of these axial sites was excellent (97.0%, 97.0%, 96.5%, and 97.1%, respectively); however, the sensitivity was poor (58.8%, 36.4%, 21.8%, and 20.3%, respectively). Therefore, the WHO criterion is not appropriate for DXA calcaneus. Based on femoral neck BMD for detection of osteoporosis, a more appropriate calcaneus T score threshold would be -1.4 by analyses of receiver-operator characteristic curves; this might serve to select those patients who might appropriately be referred for axial DXA. [ABSTRACT FROM AUTHOR]

Quantitative computed tomography (QCT) was compared to dual X-ray absorptiometry (DXA) measured in the lumbar spine of 508 European women defined as normal without fracture (NoF), or osteoporotic (OP), with either vertebral fracture (VF), or peripheral fracture (PF). The correlations between QCT and DXA BMD measurements were significantly different in normal and in osteoporotic patients, indicating that the two exams do not measure the same bone aspects. According to ROC curves results, QCT Z-scores separate OP from NoF with better sensitivity than all other measurements. A threshold to differentiate OP from NoF was chosen at Z-score = -1 for DXA-BMD and -1.5 for QCT-BMD. VF patients showed a highly significant decrease in BMD by DXA or QCT. PF patients revealed measurements lower than those of normal subjects but greater than those of VF, calling into question the idea of a diffuse osteoporosis causing nonvertebral fractures that is measurable by spinal DXA or QCT. DXA is weakly dependent upon age, and T-score or Z-score are equivalent for evaluating osteoporosis. QCT depends greatly upon age, and Z-score appears to be more efficient. [ABSTRACT FROM AUTHOR]

Metastatic bone disease is an important clinical problem which has proven difficult to study because of a lack of noninvasive investigative modalities. Here we show that dual-energy X-ray absorptiometry (DXA) scanning provides clinically useful information about the status of metastatic bone lesions in cancer patients undergoing palliative treatment. In the study group of 21 patients, a significant increase in metastatic bone mineral density (BMD) was confirmed in prostate ( n=14) relative to breast ( n=7) cancer patients. With respect to the prostate cancer cohort, further increases in lesional BMD were evident in all evaluable patients in whom biochemical progression occurred; conversely, lesional BMD declined in patients who had a partial response to therapy. BMD of uninvolved bone decreased with all types of androgen-deprivation therapy regardless of whether patients responded or relapsed. We conclude that BMD changes in both lesional and uninvolved bone are readily detectable in metastatic prostate cancer, and propose that DXA scanning represents a promising new approach to monitoring the natural history and therapeutic course of this disease. [ABSTRACT FROM AUTHOR]

: The accurate identification of prevalent vertebral fractures is important in both the clinical and research setting as they are associated with increased risk of further fracture and irreversible clinical consequences. This study reports a direct comparison of prevalent vertebral deformity identification using X-ray absorptiometry (XA) scans, acquired on a dual-energy X-ray absorptiometry (DXA) machine, and conventional radiographs in a diverse group of 161 postmenopausal women, ranging from healthy subjects with normal bone mineral density (BMD) to osteoporotic subjects with multiple vertebral deformities. Deformities were identified by a trained operator by visual assessment of the XA scans (VXA) and semiquantitatively by an experienced radiologist on the conventional radiographs (XSQ). Subjects were recruited prospectively and were triaged according to their VXA results into normal, equivocal and definite deformity groups. VXA and XSQ demonstrated good agreement (96.3%, κ= 0.79) in classifying vertebrae as normal or deformed in the 1978 of 2093 vertebrae deemed analyzable on both the XA scans and conventional radiographs. VXA showed good sensitivity (91.9%) in the identification of moderate/severe XSQ deformities and an excellent negative predictive value (98.0%) was produced when VXA was used to distinguish subjects without vertebral deformities from those with possible or definite deformities on a per subject basis. The majority of disagreement between the two methods resulted from different classification of mild wedge and endplate deformities and the poor visualization of upper thoracic vertebrae on the XA scans. Agreement improved, particularly on a per subject basis, when analysis was restricted to the vertebral levels from L4 to T7. Visual triage of XA scans by a trained operator would seem to be swift, convenient and cost-effective method, with excellent negative predictive value, to distinguish subjects with very low risk of vertebral deformities from those with possible deformities. These ‘normal’ subjects can then be excluded prior to performing conventional radiographs and further time-consuming and costly methods of vertebral deformity assessment such as XSQ by an experienced radiologist and/or quantitative morphometry. VXA may prove useful in the clinical evaluation of patients at risk of osteoporosis as an adjunct to BMD scans or in the selection of subjects for osteoporosis-related clinical trials. [ABSTRACT FROM AUTHOR]

: On radiation safety grounds there is concern about the morbidity attributable to routine radiographs of the spine for the identification of new fractures in large-scale trials of fracture prevention. However, the role of the potentially safer low-radiation-dose technique of vertebral morphometry performed by third generation dual-energy X-ray absorptiometry equipment requires evaluation for use in clinical trials. We have therefore investigated the short-term inter-scan imprecision as well as the imprecision attributable to different-day analyses by the same operator and differences in analyses by different operators. The volunteer subjects were participants in a pilot study for a randomized controlled trial of hormone replacement therapy (Women”s International Study of long Duration Oestrogen after Menopause, WISDOM). Each subject had two morphometric X-ray analysis scans separated by 2–4 weeks. Exclusions were women with densitometrically defined osteoporosis, as defined by the WHO criterion, and women with a body mass index exceeding 30.9 kg/m2. On average, the women were 58.7 years of age and had bone mineral density values in the lumbar spine which were about 0.7 SD units higher than a reference US female age-matched population. Scans were assessed from vertebrae T7 through L4. In the study there were no clinically significant differences in performance between the Hologic QDR 4500A and the Lunar Expert XL equipment. Between-scan imprecision was significantly worse than imprecision attributable to reanalysis of the same scan by a different operator or the same operator after an interval. Vertebral level had an effect on measurement uncertainty, especially at the level of the diaphragm and at T7. Coefficients of variation, expressed as percentages of mean values, were better for absolute height measurements than for height ratios, ranging from 1.75% to 3.40% for the three heights measured on three separate machines and from 2.34% to 4.11% for the two height ratios. These results compared favorably with the equivalent figures from a parallel study of morphometry precision undertaken using standard lateral radiographs of the thoracic and lumbar spine (3.1–3.6% and 3.8–3.9%, respectively). We conclude that in trials of prevention therapy in women (or men) selected for not having osteoporosis, low-dose vertebral morphometry using the Hologic 4500A, the Lunar Expert XL or similar equipment is preferable on safety grounds to the classical technique based on standard radiographs, although conventional radiology may still be required in those with prevalent or incident deformities to exclude causes other than osteoporosis. The place of this low-dose technique in trials performed on patients with osteoporosis requires further study. [ABSTRACT FROM AUTHOR]

: The diagnostic use of BMD should be cautious as BMD is not an ideal measure of true bone density; it is not an ideal measure of bone strength; it does not predict fractures well; and it has inherent problems of accuracy and linearity. The limitations of BMD, based on the physical deficiencies of DXA, are further obscured by the introduction of T-scores. It is suggested that BMD and BMC, when used diagnostically and for fracture risk classification, be used after correction for body size and/or bone size, age and sex, and that measured values be evaluated in the light of established mean fracture incidence data. BMD is not a parameter of sufficient validity to be the sole indicator of present and future fracture risk. A low BMD should be regarded one of several fracture risk factors. It seems that there is a need to redefine the T-score based definition of osteoporosis. [ABSTRACT FROM AUTHOR]