How can we measure bone quality?

Three-dimensional-printed replica models of bone for experimentally decoupling trabecular bone properties contribution to ultrasound propagation parameters

A detailed investigation of the relationship between ultrasonic (US) properties and trabecular bone microstructure is difficult because of the great variability in the bone loss process. The aim of this work was twofold. First, to verify by compressive tests that the three-dimensional (3D)-printer is able to produce precisely and repeatedly "bone replica models" of different size and density. Following, replicas of the original specimens with two different polymers and thinned trabeculae models were used to investigate US properties (speed of sound, SOS, and backscatter coefficient), aiming to deconvolute the influence of material properties on ultrasound characteristics. The results revealed that matrix material properties influence only the magnitude of the backscatter coefficient, whereas the characteristic undulated patterns are related to the trabecular structure. Simulation of perforation and thinning of cancellous bone, associated with bone loss, showed that SOS and mechanical properties were reduced perfectly linearly with apparent density when structure deteriorated. The 3D-printed bone replicas have the potential to enable systematic investigations of the influence of structure on both acoustical and mechanical properties and evaluate changes caused by bone loss. The development of replicas from materials with properties close to those of bone will permit quantitative conclusions for trabecular bone.

Meta-Analysis of Genome-Wide Association Studies Identifies Three Loci Associated With Stiffness Index of the Calcaneus

The stiffness index (SI) from quantitative ultrasound measurements is a good indicator of BMD and may be used to predict the risk of osteoporotic fracture. We conducted a genomewide association study (GWAS) for SI using 7742 individuals from the Taiwan Biobank, followed by a replication study in a Korean population (n = 2955). Approximately 6.1 million SNPs were subjected to association analysis, and SI-associated variants were identified. We further conducted a meta-analysis of Taiwan Biobank significant SNPs with a Korean population-based cohort. Candidate genes were prioritized according to epigenetic annotations, gene ontology, protein-protein interaction, GWAS catalog, and expression quantitative trait loci analyses. Our results revealed seven significant single-nucleotide polymorphisms (SNPs) within three loci: 7q31.31, 17p13.3, and 11q14.2. Conditional analysis showed that three SNPs, rs2536195 (CPED1/WNT16), rs1231207 (SMG6), and rs4944661 (LOC10050636/TMEM135), were the most important signals within these regions. The associations for the three SNPs were confirmed in a UK Biobank estimated BMD GWAS; these three cytobands were replicated successfully after a meta-analysis with a Korean population cohort as well. However, two SNPs were not replicated. After prioritization, we identified two novel genes, RAB15 and FNTB, as strong candidates for association with SI. Our study identified three SI-associated SNPs and two novel SI-related genes. Overall, these results provide further insight into the genetic architecture of osteoporosis. Further studies in larger East Asian populations are needed. © 2019 American Society for Bone and Mineral Research.

Peak Bone Mass and Quantitative Ultrasound Bone Properties in Young Adulthood: A Study in the PEAK-25 Cohort of Women

Peak bone mass is normally reached in the third decade of life. Previously, in the population-based PEAK-25 cohort (n = 1061, age 25.5 ± 0.2), we demonstrated that bone mineral density in the population-based PEAK-25 cohort is comparatively high; therefore, this study aimed to determine if the calcaneus microarchitecture mirrored this. In the process, we describe normative quantitative ultrasound (QUS) values for 25-yr-old women and the relationship between QUS values and extremes of body weight. QUS variables speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index were measured. Young adult values were based on the manufacturer-supplied QUS reference values. Analyses were performed in the cohort as a whole, and additionally, to understand the relationship between body weight and QUS values in young women, the variables were categorized into octiles for weight or body mass index (BMI) and the lowest and highest octiles were compared. In the cohort, SOS values, reflecting bone density, were higher (108 ± 18%), whereas BUA values, reflecting bone complexity, were lower (90 ± 14%) compared to the young adult reference population. SOS did not correlate with body weight or BMI. In the cohort, overall correlations between BUA weight, and BMI were small and positive (Pearson's r coefficients 0.261 and 0.197, respectively; p < 0.001), although in the low-weight group, r coefficients were higher (r = 0.313 and 0.268; p < 0.05). In contrast, in the high-weight group, correlation with BUA values tended to be small, negative, and nonsignificant. Correlation between QUS and dual-energy X-ray absorptiometry-measured bone mineral density was low to moderate and significant at all skeletal sites (r = 0.37-0.52). Whereas coefficients tended to be higher in the low-weight group, the reverse was apparent for the low-BMI group. In these 25-yr-old women, a comparatively high dual-energy X-ray absorptiometry-measured bone mass is offset by less complex bone structures assessed by QUS. This may have implications for later osteoporosis assessment and future fracture risk.

Cylinders or walls? A new computational model to estimate the MR transverse relaxation rate dependence on trabecular bone architecture

OBJECTIVE

Bone density is distributed in a complex network of interconnecting trabecular plates and rods that are interspersed with bone marrow. A computational model to assess the dependence of the relaxation rate on the geometry of bone can consider the distribution of bone material in the form of two components: cylinders and open walls (walls with gaps). We investigate whether the experimentally known dependence of the transverse relaxation rate on the trabecular bone structure can be usefully interpreted in terms of these two components.

MATERIALS AND METHODS

We established a computer model based on an elementary computational cell. The model includes a variable number of open walls and infinitely long cylinders as well as multiple geometric parameters. The transverse relaxation rate is computed as a function of these parameters. Within the model, increasing the trabecular spacing with a fixed trabecular radius is equivalent to thinning the trabeculae while maintaining constant spacing.

RESULTS

Increasing the number of cylinder and wall gap elements beyond their nearest neighbors does not change the transverse relaxation rate. Although the absolute contribution to the relaxation due to open walls is on average more important than that due to cylinders, the latter drops off rapidly. The change on transverse relaxation rate is larger for changing cylinder geometry than for changing wall geometry, as it can be seen from the effect on the relaxation rate when trabecular spacing is varied, compared to varying the size of wall gaps.

CONCLUSION

Our results provide strong evidence that trabecular thinning, which is associated with increasing age, decreases the relaxation rates. The effect of thinning plates and rods on the transverse relaxation can be understood in terms of simple cylinders and open walls. A reduction in the relaxation rate can be seen as an indication of thinning cylinders, corresponding to reduced bone stability and ultimately, osteoporosis.

Interrelationships between tooth properties and biochemical bone turnover markers investigated on six-month-old pig model

The aim of the study was to determine interrelationships between bone tissue metabolism indices and morphological, biomechanical and densitometric properties of hard dental tissues. First primary maxillary incisor from 6-month-old pigs (N=27) was evaluated in terms of weight and length. Mean volumetric tooth mineral density, total tooth volume, enamel total volume, enamel volumetric mineral density, dentine total volume and dentine volumetric mineral density were estimated with the use of quantitative computed tomography and micro computed tomography techniques. Tooth mineral density and tooth mineral content were evaluated with the use of dual-energy X-ray absorptiometry. Microhardness of enamel was measured using Vicker's test. Evaluations of total calcium, ionized calcium, magnesium, phosphorus, alkaline phosphatase, bone alkaline phosphatase, osteocalcin, C-terminal telopeptide of type-I collagen (CTX), insulin-like growth factor-1, growth hormone and parathyroid hormone were performed in plasma and serum samples. Pearson's correlation coefficients were determined between all the investigated variables, and P<0.05 was considered as statistically significant. The obtained results have shown mainly mutual dependences between biochemical indicators of bone metabolism. Evaluation of CTX concentration in serum of pigs has shown the highest predictive value in relation to morphological, densitometric and biomechanical properties of teeth.

Pharmacological evaluation of LiuWei Zhuanggu Granules in rats

Many commonly consumed foods, herbs and spices contain a complex array of naturally occurring bioactive molecules called phytochemicals, which may confer health benefits. In this study, the impact of LiuWei Zhuanggu Granules (LWZGG) on mineral metabolism in osteopenia development was evaluated. Results showed that serum estrogen, bone gla protein (BGP), and calcitonin (CT) levels, bone Ca, Zn and Cu levels, femur, lumbar vertebrae and trabecular bone density, tibia maximum stress and maximum bending strength were increased, and serum parathyroid hormone (PTH), serum and urine Ca, Zn and Cu levels were decreased in rat bone. It can be concluded that LWZGG is useful to improve bone quality in ovariectomized (OVX) rats.

Locally administrated perindopril improves healing in an ovariectomized rat tibial osteotomy model

Angiotensin-converting enzyme inhibitors are widely prescribed to regulate blood pressure. High doses of orally administered perindopril have previously been shown to improve fracture healing in a mouse femur fracture model. In this study, perindopril was administered directly to the fracture area with the goal of stimulating fracture repair. Three months after being ovariectomized (OVX), tibial fractures were produced in Sprague–Dawley rats and subsequently stabilized with intramedullary wires. Perindopril (0.4 mg/kg/day) was injected locally at the fractured site for a treatment period of 7 days. Vehicle reagent was used as a control. Callus quality was evaluated at 2 and 4 weeks post-fracture. Compared with the vehicle group, perindopril treatment significantly increased bone formation, increased biomechanical strength, and improved microstructural parameters of the callus. Newly woven bone was arranged more tightly and regularly at 4 weeks post-fracture. The ultimate load increased by 66.1 and 76.9% (p<0.01), and the bone volume over total volume (BV/TV) increased by 29.9% and 24.3% (p<0.01) at 2 and 4 weeks post-fracture, respectively. These findings suggest that local treatment with perindopril could promote fracture healing in ovariectomized rats.

Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice

Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Mice deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1(-/-) mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1(-/-) mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm(2)) and strength (MPa) is diminished in Sod1(-/-) compared to WT mice. Femurs were obtained from male and female WT and Sod1(-/-) mice at 8months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1(-/-) mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1(-/-) mice compared to WT as well as between genders. These data indicate that increased oxidative stress, due to the deficiency of Sod1 is associated with decreased bone stiffness and strength and Sod1(-/-) mice may represent an appropriate model for studying disease processes in aging bone.

Du-Zhong (Eucommia ulmoides Oliv.) cortex extract prevent OVX-induced osteoporosis in rats

Du-Zhong, rich in polyphenolic compounds such as lignans, phenolic acid, and flavonoids, is a kidney-tonifying herbal medicine with a long history of safe use for treatment of bone fractures and joint diseases in China. In the present study, we examined whether Du-Zhong cortex extract (DZCE) with graded doses exerted its preventive effects on estrogen deficiency-induced osteoporosis. Eighty 3-month-old female Sprague-Dawley rats were used and randomly assigned into sham-operated group (Sham) and five ovariectomy (OVX) subgroups, i.e. OVX with vehicle (OVX); OVX with 17alpha-ethinylestradiol (E(2), 25 microg/kg/day); OVX with DZCE of graded doses (100, 300, or 500 mg/kg/day). Daily oral administration of DZCE or E(2) started on week 4 after OVX for 16 weeks. Treatment with DZCE at higher doses (300 or 500 mg/kg/day) was found to be able to significantly prevent OVX-induced decrease in biomechanical quality of femur such as maximum stress and Young's modulus. The mechanical changes were associated with the prevention of a further bone mineral density (BMD) decrease or even with some improvements in microarchitecture. DZCE dose-dependently inhibited total BMD decrease in the femur caused by OVX, which was accompanied by a significant decrease in skeletal remodeling, as was evidenced by the decreased levels of the bone turnover markers osteocalcin (OC), alkaline phosphatese (ALP), deoxypyridinoline (DPD), and urinary Ca and P excretions. muCT analysis of the femoral metaphysis showed that DZCE at the highest doses (500 mg/kg/day) significantly prevents decrease in bone volume/tissue volume (BV/TV), connect density (Conn.D), trabecula number (Tb.N) and trabecula thickness (Tb.Th), and increase in trabecula separation (Tb.Sp) and structure model index (SMI) in OVX rats. We conclude that 16 weeks of DZCE treatment improves bone biomechanical quality through modifications of BMD, and trabecular microarchitecture without hyperplastic effect on uterus, and it might be a potential alternative medicine for treatment of postmenopausal osteoporosis.

Trabecular bone mechanical properties in patients with fragility fractures

Fragility fractures are generally associated with substantial loss in trabecular bone mass and alterations in structural anisotropy. Despite the high correlations between measures of trabecular mass and mechanical properties, significant overlap in density measures exists between individuals with osteoporosis and those who do not fracture. The purpose of this paper is to provide an analysis of trabecular properties associated with fragility fractures. While accurate measures of bone mass and 3-D orientation have been demonstrated to explain 80% to 90% of the variance in mechanical behavior, clinical and experimental experience suggests the unexplained proportion of variance may be a key determinant in separating high- and low-risk patients. Using a hierarchical perspective, we demonstrate the potential contributions of structural and tissue morphology, material properties, and chemical composition to the apparent mechanical properties of trabecular bone. The results suggest that the propensity for an individual to remodel or adapt to habitual damaging or nondamaging loads may distinguish them in terms of risk for failure.

Bone mass in schizophrenia and normal populations across different decades of life

BACKGROUND

Chronic schizophrenic patients have been reported as having higher osteoporosis prevalence. Survey the bone mass among schizophrenic patients and compare with that of the local community population and reported data of the same country to figure out the distribution of bone mass among schizophrenic patients.

METHODS

965 schizophrenic patients aged 20 years and over in Yuli Veterans Hospital and 405 members aged 20 and over of the community living in the same town as the institute received bone mass examination by a heel qualitative ultrasound (QUS) device. Bone mass distribution was stratified to analyzed and compared with community population.

RESULTS

Schizophrenic patients have lower bone mass while they are young. But aging effect on bone mass cannot be seen. Accelerated bone mass loss during menopausal transition was not observed in the female schizophrenic patients as in the subjects of the community female population.

CONCLUSION

Schizophrenic patients have lower bone mass than community population since they are young. Further study to investigate the pathophysiological process is necessary to delay or avoid the lower bone mass in schizophrenia patients.

Feasibility of micro-crack detection in human trabecular bone images from 3D synchrotron microtomography

Bone micro-cracks receive an increasing attention to explain bone quality. They have mainly been observed in 2D with microscopic techniques. In this paper, we propose a method based on 3D Synchrotron Radiation micro-CT to analyze micro-cracks in human trabecular bone samples. Samples were imaged with a voxel size of 1.4 microm. Despite micro-cracks are visible, their automatic detection is challenging because of noise, artifacts, low-contrast, and partial volume effect. We propose a two-steps procedure, based on image enhancement and segmentation to address this problem. The method enables to get the 3D morphology of micro-cracks, shown for the first time with this precision. Future work will be devoted to extract quantitative parameters on the crack morphology.

Prevalence of osteoporosis in middle Anatolian population using calcaneal ultrasonography method

BACKGROUND

There are a few studies on the prevalence of osteoporosis in Turkey. Most of such studies have been performed using classical diagnostic methods. Quantitative calcaneal ultrasonography is a contemporary procedure used in the diagnosis of osteoporosis.

OBJECTIVE

The aim of this study is to determine the prevalence of the osteoporosis and risk factors in middle Anatolian population aged more than 40, using quantitative calcaneal ultrasonography.

SUBJECTS AND METHODS

The present study was carried out in rural and urban areas of primary health care units. Evaluation of skeletal status was based on calcaneal quantitative ultrasound measurement, carried out by the Sahara Clinical Bone Sonometer (Hologic Waltham, MA, USA).

RESULTS

There were 1437 individuals, 866 were females (60.3%) and 571 were males (39.7%), aged in between 40 and 89 years. Standardized prevalence rates using Segi's population were found to be 14.0% in total, 17.1% in female and 9.2% in male. Osteoporosis prevalence increased with increasing ages. The highest prevalence value was determined in the individuals older than 70 years of age. Osteoporosis was more common among women compared to men. Osteoporosis prevalence increased in consistent with a decrease in the amount of milk, yoghurt and cheese consumption.

CONCLUSION

Based on current study, it is concluded that osteoporosis is an important health problem. Requiring health education about life styles (activity and nutrition) to avoid and even control osteoporosis.

Ultrasonic guided waves in bone

Recent progress in quantitative ultrasound (QUS) has shown increasing interest toward measuring long bones by ultrasonic guided waves. This technology is widely used in the field of nondestructive testing and evaluation of different waveguide structures. Cortical bone provides such an elastic waveguide and its ability to sustain loading and resist fractures is known to be related to its mechanical properties at different length scales. Because guided waves could yield diverse characterizations of the bone's mechanical properties at the macroscopic level, the method of guided waves has a strong potential over the standardized bone densitometry as a tool for bone assessment. Despite this, development of guided wave methods is challenging, e.g., due to interferences and multiparametric inversion problems. This paper discusses the promises and challenges related to bone characterization by ultrasonic guided waves.

Determination of bone's mechanical matrix properties by nanoindentation

Osteoporosis is a devastating disease that is characterized not only by a reduction in bone quantity but also by deterioration in bone quality. The quality of bone tissue is greatly influenced by its mechanical properties and, therefore, investigations into the etiology and enhanced detection of osteoporosis, or the efficacy of interventions, may require the assessment of bone's mechanical properties at the level of the tissue. Nanoindentation is a relatively new technique that is capable of evaluating bone's quasi-static and dynamic mechanical properties on extremely small volumes of tissue. These data can be used directly to describe the pre-yield properties of the matrix, but can also be combined with imaging techniques and mechanical models to extrapolate the mechanical properties from the level of the tissue to that of the organ.

Evaluation of trabecular mechanical and microstructural properties in human calcaneal bone of advanced age using mechanical testing, microCT, and DXA

Early detection of fracture risk is important for initiating treatment and improving outcomes from both physiologic and pathologic causes of bone loss. While bone mineral density (a quantity measure) has traditionally been used for this purpose, alternative structural imaging parameters (quality measures) are proposed to better predict bone's true mechanical properties. To further elucidate this, trabecular bone from cadaveric human calcanei were used to evaluate the interrelationship of mechanical and structural parameters using mechanical testing, dual energy X-ray absorptiometry (DXA) scanning, and micro computed tomography (microCT) imaging. Directional specific structural properties were assessed in three-dimensional (3-D) and correlated to mechanical testing and DXA. The results demonstrated that microCT-derived indices of bone quality (i.e., volume fraction and structural model index) are better than DXA-derived bone mineral density for the prediction of the mechanical parameters of bone (i.e., elastic modulus, yield stress, and ultimate stress). Diagnostically, this implies that future work on the early prediction of fracture risk should focus as much on bone quality as on quantity. Furthermore, the results of this study show that a loss of bone primarily affects the connectedness and overall number of trabeculae. Ultimate stress, however, is better correlated with trabecular number than thickness. As such, primary prevention of osteoporosis may be more important than later countermeasures for bone loss.

Bone health in children and adolescents after allogeneic stem cell transplantation

BACKGROUND

This cross-sectional study evaluated the overall bone health and the prevalence of vertebral complications after stem cell transplantation (SCT) in prepubertal children and adolescents.

METHODS

A total of 44 children and adolescents (median age, 10 years) were evaluated at a median of 3.8 years after SCT for areal bone mineral density (aBMD) with dual-energy X-ray absoptiometry and for vertebral fractures with instant vertebral assessment. Pretransplant and posttransplant medications and nutritional parameters were recorded, and plasma levels of vitamin D, calcium, phosphate, and parathormone were measured.

RESULTS

Of the 44 patients, 16 (36%) had a BMD Z-score of <-1.0. The patients with low BMD did not differ from the others with regard to their clinical or biochemical characteristics. Prepubertal patients had better BMD Z-scores at all sites compared with pubertal or postpubertal subjects. This was evident especially at the hip, in which the median aBMD Z-score in prepubertal patients (-0.2; range, -0.5 to +1.7) was found to be significantly higher than in pubertal (-1.1; range, -1.5 to +0.4) and postpubertal (-1.1; range, -2.6 to +0.5) patients (P = .03). Five patients (11%) had a history of peripheral fractures. Nine patients (20%) had vertebral compression fractures, which were asymptomatic in 7 patients.

CONCLUSIONS

Approximately one-third of patients who had undergone allogeneic SCT in childhood were found to have a reduced BMD before reaching adulthood. This was due in part to inadequate BMD gain during the pubertal years. The high prevalence of asymptomatic vertebral compression fractures calls for the systematic assessment of spinal health during the posttransplantation follow-up.

Infrared imaging microscopy of bone: illustrations from a mouse model of Fabry disease

Bone is a complex tissue whose composition and properties vary with age, sex, diet, tissue type, health and disease. In this review, we demonstrate how infrared spectroscopy and infrared spectroscopic imaging can be applied to the study of these variations. A specific example of mice with Fabry disease (a lipid storage disease) is presented in which it is demonstrated that the bones of these young animals, while showing typical spatial variation in mineral content, mineral crystal size, and collagen maturity, do not differ from the bones of age- and sex-matched wild type animals.

Increase in bone mass and bone strength by Sambucus williamsii HANCE in ovariectomized rats

Herbal Sambucus williamsii HANCE (SWH) is a folk medicine with a long history of safe use for treatment of bone fractures and joint diseases in China. The present study was designed to investigate if SWH extract could be used for treatment of postmenopausal osteoporosis. SWH extracts (30 or 60 mg/100 g body weight/d) were orally administrated to four-months-old ovariectomized (OVX) rats for 3 months. SWH extracts did not alter weight gain and uterus weight in OVX rats. SWH extracts significantly increased serum Ca levels (p<0.05, vs. OVX control group) as well as decreased urinary Ca excretion (p<0.01, vs. OVX control group) in OVX rats. The upregulation of serum alkaline phosphatase, serum osteocalcin as well as urinary deoxypyridinoline levels by OVX was suppressed by treatment with SWH extracts in rats (p<0.05, vs. OVX control group). SWH extract increased the stiffness of femur at both dosage (p<0.05, vs. OVX control group) and increased tibial bone mineral density at 60 mg/100 g body weight/d (p<0.05, vs. OVX control group) in OVX rats. Our results indicate that orally administrated SWH extracts can decrease urinary calcium excretion and bone turnover rate in OVX rats, resulting in positive effects on biomechanical strength of bone and bone mineral density. This study is the first to report that SWH could be considered as a potential candidate for management of postmenopausal osteoporosis. Then in vitro experiments were performed to determine the potential molecular mechanism of the anti-osteoporotic effect of SWH. Results suggested that chloroform fraction and ethyl acetate fraction of SWH can inhibit osteoclastogenesis osteoclast by modulating the expression of osteoprotegrin (OPG) and receptor activator of NF-kappaB ligand (RANKL) mRNA in osteoblastic UMR 106 cells. Both of them increased OPG mRNA and decreased RANKL mRNA expression, resulting in a dose-dependent increase in OPG/RANKL mRNA ratio (p<0.01, vs. vehicle-treated). Taken together, SWH treatment can effectively suppress the OVX-induced increase in bone turnover and its effects might be mediated by a decrease in osteoclastogenesis.

Middle-aged premenopausal women with type 1 diabetes have lower bone mineral density and calcaneal quantitative ultrasound than nondiabetic women

OBJECTIVE

To determine whether middle-aged premenopausal women with type 1 diabetes had more self-reported fractures and lower bone mineral density (BMD) compared with nondiabetic women.

RESEARCH DESIGN AND METHODS

Participants were premenopausal women aged 35-55 years with type 1 diabetes (n = 67; 32.2 +/- 5.3 years duration) and without diabetes (n = 237). Total hip, femoral neck, whole-body, and spine BMD were measured by dual X-ray absorptiometry. Calcaneal broadband ultrasound attenuation (BUA) was assessed with quantitative ultrasound.

RESULTS

Women with type 1 diabetes were more likely to report a fracture after age 20 years compared with nondiabetic women (33.3 vs. 22.6%; age-adjusted odds ratio 1.89 [95% CI 1.02-3.49]). Type 1 diabetes was associated with lower total hip BMD (0.890 vs. 0.961 g/cm2; P < 0.001), femoral neck BMD (0.797 vs. 0.847 g/cm2; P = 0.001), whole-body BMD (1.132 vs. 1.165 g/cm2; P < 0.01), and lower calcaneal BUA (71.6 vs. 84.9 dB/MHz; P < 0.001) after multivariate adjustment. BMD was 3-8% lower in type 1 diabetic compared with control women and calcaneal BUA was 15% lower. Spine BMD and biomarkers of bone remodeling were not significantly different between groups. In the type 1 diabetic women, reduced monofilament detection and blindness were both associated with lower BMD.

CONCLUSIONS

Lower BMD in premenopausal women with type 1 diabetes may substantially increase their risk of developing osteoporosis after menopause. Type 1 diabetic women should be targeted for osteoporosis screening and possible fracture prevention as they transition through menopause.

Postmenopausal women with Colles' fracture have bone mineral density values similar to those of controls when measured with calcaneus quantitative ultrasound

BACKGROUND

It is a matter of controversy whether or not Colles' fracture is an osteoporotic fracture. Indeed, the usefulness of quantitative ultrasound in distinguishing Colles' fracture from normal fractures is also unclear.

METHODS

A cross-sectional case-control study was done on 469 postmenopausal Spanish women, 121 with Colles' fracture and 348 controls. Assessment of risk factors for osteoporosis and measurement of calcaneus quantitative ultrasound were carried out using a Sahara, Hologic device.

RESULTS

Patients with Colles' fracture had BUA, SOS, and QUI values that were similar to those of controls, and no statistically significant differences were found. We estimated ROC curves for SOS and a score based on a linear combination of height and SOS (SH-Score). The areas under both curves were 0.56 and 0.61, respectively, which was statistically significant. To obtain 5% false-negative and 10% false-positive figures, the T-score cut-off for SOS was -2.45 and -0.045, respectively. Of these, only 9.2% were classified as high risk and 11% as low risk with 79.8% undetermined.

CONCLUSIONS

Patients with Colles' fracture had BUA, SOS, and QUI values that were similar to those of controls. Nevertheless, ROC curves calculated by a combination of height and SOS showed that quantitative calcaneus ultrasound may be a useful tool for identifying postmenopausal women with Colles' fracture. These results indicate that measuring bone mineral density with ultrasound only captures limited aspects of the pathophysiology of Colles' fractures.

Interrelationship of trabecular mechanical and microstructural properties in sheep trabecular bone

The ability to evaluate fracture risk at an early time point is essential for improved prognostics as well as enhanced treatment in cases of bone loss such as from osteoporosis. Improving the diagnostic ability is inherent upon both high-resolution non-invasive imaging, and a thorough understanding of how the derived indices of structure and density relate to its true mechanical behavior. Using sheep femoral trabecular bone with a range of strength, the interrelationship of mechanical and microstructural parameters was analyzed using multi-directional mechanical testing and micro-computed tomography. Forty-five cubic trabecular bone samples were harvested from 23 adult female sheep, some of whom had received hind-limb vibratory stimuli over the course of 2 years with consequently enhanced mechanical properties. These samples were pooled into a low, medium, or high strength group for further analysis. The findings show that microCT indices that are structural in nature, e.g., structural model index (SMI) (r2=0.85, p<0.0001) is as good as more density oriented indices like bone volume/total volume (BV/TV) (r2=0.81, p<0.0001) in predicting the ultimate strength of a region of trabecular bone. Additionally, those indices more related to global changes in trabecular structure such as connectivity density (ConnD) or degree of anisotropy (DA) are less able to predict the mechanical properties of bone. Interrelationships of trabecular indices such as trabecular number (TbN), thickness (TbTh), and spacing (TbSp) provide clues as to how the trabecular bone will remodel to ultimately achieve differences in the apparent mechanical properties. For instance, the analysis showed that a loss of bone primarily affects the connectedness and overall number of trabeculae, while increased strength results in an increase of the overall thickness of trabeculae while not improving the connectedness. Certainly, the microCT indices studied are able to predict the bulk mechanical properties of a trabecular ROI well, leaving unaccounted only about 15-20% of its inherent variability. Diagnostically, this implies that future work on the early prediction of fracture risk should continue to explore the role of bone quality as the key factors or as an adjuvant to bone quantity (e.g., apparent density).

Ankylosing spondylitis and bone mineral density--what is the ideal tool for measurement?

Ankylosing spondylitis (AS) is characterised by chronic inflammation and partial ossification, yet vertebral fractures due to osteoporosis, although common, are frequently unrecognised. The aim of this study was to (1) show the frequency of changes in the progress of osteopenia/osteoporosis in AS depending on duration and stage of the disease and (2) assess the ranking of two different methods of bone density measurement in this clinical pattern. We measured bone density in 84 male and female patients with both dual X-ray absorptiometry (DXA) and single energy quantitative computed tomography (SE-QCT). In the initial and advanced stages of the disease, a high decrease in axial bone density could be verified (DXA: osteopenia in 5% and osteoporosis in 9.2%; SE-QCT: osteopenia in 11.8% and osteoporosis in 30.3%). Peripheral bone density decrease as in osteopenia could be proven in 17.6% by DXA measurement. With SE-QCT, a decrease in vertebral trabecular bone density could already be observed in the initial stage and continued steadily during the course of the disease; cortical bone displayed the same trend up to stages of ankylosis. With DXA, valid conclusions are more likely to be expected in less marked ankylosing stages of AS. In stages of advanced ankyloses in the vertebral region (substantial syndesmophytes), priority should be given to SE-QCT, due to the selective measurement of trabecular and cortical bone. The DXA method often yields values that are too high, and the replacement of vertebral trabecular bone by fatty bone marrow is not usually recorded as standard. There may already be an increased risk of bone fracture in AS in osteopenia on DXA along with an osteoporosis already established on SE-QCT.

Interleukin-6 promoter polymorphism is associated with bone quality assessed by calcaneus ultrasound and previous fractures in a cohort of 75-year-old women

Interleukin 6 (IL-6) is a multifunctional cytokine and a potent stimulator of bone resorption and has been implicated in the pathogenesis of osteoporosis in postmenopausal women. The aim of this study was to investigate if a functional IL-6 promoter polymorphism (-174) was related to bone mass and fractures in a cohort consisting of 964 postmenopausal Caucasian women aged 75 years. Bone mineral density (BMD; g/cm2) of the femoral neck, lumbar spine and total body was measured using dual energy X-ray absorptiometry (DXA). Quantitative ultrasound (QUS) was also measured in the calcaneus and quantified as speed of sound (SOS; m/s), broadband ultrasound attenuation (BUA; dB/MHz), and stiffness index (SI). IL-6 genotypes was determined by restriction fragment length polymorphism (RFLP) using the restriction enzyme NlaIII. The frequencies of the different IL-6 genotypes were 27.5% (GG), 47.9% (GC), 24.6% (CC). The IL-6 polymorphism (presence of G) was independently related to a lower stiffness (beta=-0.07; P=0.03) and BUA (beta=-0.08; P=0.02), but not to BMD at any site measured by DXA. In the cohort, 420 subjects (44%) reported at least one fracture during their lifetime, and 349 (36%) reported at least one fracture after the age of 50. Using binary logistic regression, the IL-6 polymorphism (presence of G) was significantly related to an increased risk of a previous fracture during life (odds ratio 1.46, 95% CI 1.08-1.97) and to an increased risk of a fracture occurring after 50 years of age (odds ratio 1.37, 95% CI 1.004-1.88). The risk was further increased for fractures grouped as osteoporotic fractures (odds ratio 1.67, 95% CI 1.14-2.45), including forearm fractures (odds ratio 1.59, 95% CI 1.05-2.40). In conclusion, presence of G allele in the IL-6 promoter polymorphism at position -174 is independently related to previous fractures in postmenopausal women. This association may be related primarily to an altered bone quality identified by QUS and not a lower bone mass. This is also the first demonstration of association of IL-6 gene polymorphism to calcaneal QUS.

Limited diagnostic agreement of quantitative sonography of the radius and phalanges with dual-energy x-ray absorptiometry of the spine, femur, and radius for diagnosis of osteoporosis

OBJECTIVE

The aim of our study was to evaluate the diagnostic agreement of quantitative sonography of the radius and proximal phalanx and dual-energy X-ray absorptiometry (DXA) of the radius, lumbar spine, and femoral neck for the detection of osteoporosis.

MATERIALS AND METHODS

In 95 women (mean age, 53 +/- 13 years) and 26 men (mean age, 53 +/- 13 years), DXA measurements of the lumbar spine (posterior-anterior, L1-L4) and the femoral neck, as well as quantitative sonography of the radius and proximal phalanx of the third finger were obtained. The percentage of patients below a given threshold was calculated for each imaging technique. A T score of less than -2.5 indicated presence of osteoporosis. Diagnostic agreement in identifying individuals with osteoporosis was assessed using kappa scores.

RESULTS

Between 14% and 22% of the patients were classified as osteoporotic after DXA of the various regions of interest of the radius, 31% after DXA of the spine, 43% after DXA of the femoral neck, 32% after quantitative sonography of the distal radius, and 34% after quantitative sonography of the phalanx of the third finger. Correlation coefficients between T values for quantitative sonography and those for DXA varied between not significant and 0.54 at the different regions. Kappa analysis showed the diagnostic agreement among quantitative sonography and DXA to be fair to moderate (kappa = 0.38-0.48). The highest agreement was between quantitative sonography of the proximal phalanx of the third finger and DXA of the total radius (kappa 0.48; p < 0.05).

CONCLUSION

Considerable diagnostic disagreement exists between quantitative sonography and DXA of the forearm, as is true for most quantitative techniques in the assessment of skeletal status. The lack of correlation makes quantitative sonography impractical for routine diagnostic use but might characterize different parameters related to bone quality.

Quantitative ultrasound and bone mineral density: discriminatory ability in patients with rheumatoid arthritis and controls with and without vertebral deformities

BACKGROUND

Quantitative ultrasound (QUS) is a reliable tool for discriminating between subjects with and without vertebral deformities in postmenopausal osteoporosis. Less is known about osteoporosis caused by inflammatory diseases or corticosteroid use.

OBJECTIVES

(1). To compare in patients with rheumatoid arthritis the ability of QUS and dual energy x ray absorptiometry (DXA) to discriminate between those with and without vertebral deformities; (2). to explore whether the results are similar in population based controls.

METHODS

Standardised lateral radiographs of the spine were obtained from 210 patients with rheumatoid arthritis aged over 50 years and 210 individually matched controls. Vertebral deformities were assessed morphometrically and semiquantitatively. All participants underwent bone measurements by DXA (Lunar Expert) and QUS (Lunar Achilles+). Receiver operating curve (ROC) analysis was used to compare the discriminating ability of BMD and QUS measurements in patients and controls with and without vertebral deformities. Analyses were repeated in patients stratified according to corticosteroid use.

RESULTS

For all bone measurements except lumbar spine in the rheumatoid arthritis group, BMD discriminated significantly between the patients with and without vertebral deformities, and the results were similar to those obtained in controls. Among current corticosteroid users, neither QUS nor DXA could discriminate between subjects with and without vertebral deformities.

CONCLUSIONS

These findings support QUS as an alternative tool for identifying patients at risk of having vertebral deformities in rheumatoid arthritis, although results should be interpreted with caution in current users of corticosteroids.

Quantitative ultrasound (QUS) of bone in the management of postmenopausal women

OBJECTIVES

Postmenopausal osteoporosis is becoming a major problem for healthcare institutions as it has a growing social and economic impact. The incidence of osteoporotic fractures is constantly increasing due to the increase in life expectancy. The gynaecologist plays an important role in establishing a "biological zero" in each perimenopausal patient, and controlling the rate of bone loss during postmenopausal period.

RESULTS

Dual energy X-ray absorptiometry (DXA) has been widely used for the diagnosis and management of osteoporosis and represents a strong risk factor for fractures, but it presents several limitations with regards to diagnosis, treatment follow-up and differential diagnosis of secondary osteoporosis. In these last years quantitative ultrasound (QUS) technique has been introduced for the evaluation of bone status in postmenopausal women and several in vitro and clinical studies have demonstrated the reliability of the examination in terms of: reproducibility, evaluation of fracture risk, treatment follow-up, differential diagnosis. QUS has proven to be equally capable in the prediction of future osteoporosis related fractures in comparison to DXA. Large-scale cross-sectional and longitudinal studies have demonstrated the applicability of QUS in screening the female population during the climacteric period. QUS technique seems to be very efficient in identifying "fast losers", identifying subjects at risk for osteoporosis requiring second-level investigation (DXA, X-ray), diagnosing secondary osteoporosis.

CONCLUSION

If QUS is used in a systematic and rational manner in clinical practice, it is a valid technique for the prevention of osteoporosis in postmenopausal women.

Tibial ultrasound velocity in women with wrist fracture

The aim of the study was to determine whether cortical midtibial speed of sound (Soundscan 2000, Myriad Ultrasound Systems, Israel) was able to discriminate women who sustained a fracture of the distal radius from normal women and to compare the performance of tibial speed of sound with dual-energy X-ray absorptiometry (DXA) of the distal radius, hip, and lumbar spine. The study population consisted of 40 women with a wrist fracture and 41 healthy age-matched controls. Tibial ultrasound velocity correlated with bone mineral density of the distal forearm (rS = 0.64, p < 0.001), the hip (rS = 0.46, p < 0.001), and the lumbar spine (rS = 0.51, p < 0.001). The mean speed of sound value at the mid-tibia of the wrist fracture patients (3873 m/s) was lower than that of the controls (3913 m/s), but the difference was not statistically significant (p = 0.12). All DXA values were significantly lower in fracture cases. Receiver operating curve analysis showed that mid-tibial ultrasound velocity was less effective than DXA of the distal forearm to discriminate wrist fracture patients from age-matched controls.

Effects of a herbal extract on the bone density, strength and markers of bone turnover of mature ovariectomized rats

For many decades, the Chinese have been using herbal medications to treat bone diseases. To examine effects of an extract of ten medicinal herbs on estrogen deficiency bone loss, ten-month-old female rats were randomly divided into three groups: ovariectomized (OVX), OVX treated with herbs (OVX-M) 4 ml/day by gavage, and OVX treated with estrogen (OVX-E) 10 mg subcutaneously (s.c.) twice per week. The bone mineral density (BMD) of the left femur (fBMD), spine (sBMD) and global body (gBMD) were measured at baseline and at 4, 8 and 12 weeks using a Hologic QDR 2000 dual-energy X-ray densitometer. Tibial strength was tested using the Instron Model 5566 electro-mechanical testing machine. The urinary pyridinoline creatinine ratio (Pyd/Cr), deoxypyridinoline creatinine ratio (Dpd/Cr), plasma alkaline phosphatase (ALP), calcium (CA), phosphorus (P) and albumin (ALB) were also determined. Uterine weight was determined at 12 weeks. The results showed that percent changes of fBMD in the OVX (n = 9), OVX-E (n = 8) and OVX-M (n = 8) rats at the 12-week time point were -11.8 +/- 4.6(c), 1.8 +/- 3.1(a), -7.6 +/- 1.9(abc) (p < 0.05-0.001, a: vs. OVX, b: vs. OVX-E, c: vs. baseline); sBMD were -10.7 +/- 4.6(c), -0.3 +/- 5.5(a), -5.9 +/- 3.5(abc); and gBMD were -4.8 +/- 2.3(c), 0.1 +/- 2.4(a), -2.7 +/- 2.6(abc), respectively. Further, the tibia maximum breaking stress and flexural modulus of elasticity in OVX-M rats (295 +/- 33(a), 18,194 +/- 3,264(a)) were significantly higher (p < 0.005-0.001) than that in OVX rats (189 +/- 83, 10,309 +/- 4,930), and similar to OVX-E rats (298 +/- 35(a), 18,766 +/- 2,620(a)). Additionally, the herbal extract reduced the urinary Pyd/Cr, Dpd/Cr and plasma ALP increment followed OVX and was not associated with a rise in uterine weight. In conclusion, the herbal extract demonstrated a therapeutic effect to inhibit bone resorption and to reduce estrogen-dependent bone loss without uterine stimulation. It may have potential as a new approach in treating and preventing postmenopausal osteoporosis (PMOP).

Alterations of bone mineral density and bone metabolism in patients with various grades of chronic pancreatitis

The aim of this study was to examine bone mineral density (BMD) and bone metabolism in patients with chronic pancreatitis to determine if increased severity of the disease would correlate with increased bone loss. Between October 1999 and September 2000, we investigated 42 patients with an average age of approximately 53 years suffering from chronic pancreatitis, as well as 20 healthy male controls with an average age of 49 years. Dual energy x-ray absorptiometry (DEXA) was performed on patients and controls, and serum levels of parathyroid hormone (PTH), osteocalcin (OC), carboxy-terminal propeptide of type I procollagen (CICP), bone-specific alkaline phosphatase (BAP), 1,25(OH)(2) vitamin D(3) and 25(OH) vitamin D(3), as well as fecal elastase 1 were also determined. The severity of chronic pancreatitis in patients was determined via endoscopic retrograde cholangiopancreatography (ERCP) and assigned to 1 of 3 grades based on the Cambridge classification. BMD of patients with chronic pancreatitis was markedly decreased compared to controls (means in patients: DEXA lumbar vertebra anterior/posterior (LV ap) 96.8% +/- 4.2%, DEXA Ward's triangle (WARD) 92.2% +/- 5.2%; controls: DEXA LV ap 98.7% +/- 3.7%, DEXA WARD 97.1% +/- 3.1%; P <.05 and P <.0001) and correlated with the various Cambridge-grades (DEXA LV ap and DEXA WARD, P <.01). Fecal elastase 1 showed sensitivities of 14%, 87%, and 95% for the Cambridge-grades I, II, and III, respectively, and correlated with this classification of severity of chronic pancreatitis (P <.01). Furthermore, fecal elastase 1 of patients correlated the same way with both D(3)-vitamins (P <.01), as well as with parameters of BMD (P <.01). If fecal elastase 1 in patients was below 200 micro g/g, then the BMD and vitamin D(3) values were also significantly decreased compared to those with fecal elastase 1 above 200 micro g/g. In patients with Cambridge grades II and III 1,25(OH)(2)D(3) was markedly decreased (26.7 +/- 7.7 pg/mL and 27.6 +/- 9.0 pg/mL) compared to those with Cambridge grade I (38.0 +/- 10.5 pg/mL; between I and II, P =.027; between I and III, P =.033). 25(OH)D(3) was not significantly different within the various Cambridge groups (P =.07). Compared to controls, both D(3) vitamins, as well as fecal elastase 1, were extremely low (means in patients: fecal elastase 1, 140.7 +/- 75.7 micro g/g; 1,25(OH)(2)D(3), 29.9 +/- 9.5 pg/mL; 25(OH)D(3), 26.7 +/- 9.7 nmol/L; controls: fecal elastase 1, 694.9 +/- 138.6 micro g/g; 1,25(OH)(2)D(3), 67.5 +/- 4.3 pg/mL; 25(OH)D(3), 69.5 +/- 13.5 nmol/L). A significant correlation was observed between increased severity of chronic pancreatitis based on both endoscopic retrograde cholangiopancreatography and levels of fecal elastase 1, with decreased circulating levels of vitmain D(3) and decreased BMD. This supports a connection between the inflammatory destruction of the pancreas (Cambridge classification), exocrine pancreatic insufficiency (fecal elastase 1), altered levels of vitamin D metabolites, and loss of skeletal mass.

North American male reference population for speed of sound in bone at multiple skeletal sites

Alternatives to dual-energy X-ray absorptiometry (DXA) have been sought to increase access to low-cost osteoporosis risk assessment. Early quantitative ultrasound (QUS) systems measured speed of sound (SOS) and broadband ultrasound attenuation (BUA) at the calcaneus, and these were demonstrated to be good predictors of hip fracture risk. Recent studies have demonstrated the usefulness of other peripheral sites to assess bone status. The Sunlight Omnisense (Sunlight Medical, Rehovot, Israel) is a portable, inexpensive QUS device capable of multiple-site SOS measurement. To provide a robust male reference database, 588 healthy Caucasian males aged 20-90 yr were recruited from 6 centers across North America. SOS measurements were taken at the distal 1/3 radius, proximal third phalanx, midshaft tibia, and fifth metatarsal. A female reference database has previously been collected at North American sites. The results indicate that SOS in males exhibits an age-related decline beginning in the fifth decade at the radius, phalanx, and metatarsal, whereas the tibial SOS remains nearly constant until the ninth decade. Although females reach a higher-peak SOS than males at most sites, SOS is higher in males at all sites after the sixth decade, as a result of a more gradual decline in SOS. Longitudinal monitoring of healthy men should be performed to confirm these cross-sectional results.

Brånemark implants and osteoporosis: a clinical exploratory study

BACKGROUND

Oral implant treatment on patients with poor jaw-bone texture has shown increased failure rates in series of studies.

PURPOSE

The purpose of the present study was to retrospectively follow patients with osteoporosis of the axial or appendicular skeleton, including the jaw bone, being subjected to oral implant treatment. The outcome of inserted implants, when using an adapted bone site preparation technique and extended healing periods, was evaluated.

MATERIALS AND METHODS

Based on data obtained from preoperative radiographs, patient medical history, and resistance of the jaw bone perceived during drilling, 14 of 16 patients were referred to the Osteoporosis Laboratory, Sahlgren University Hospital, Göteborg, Sweden, for bone density measurements. Two patients already had an established diagnosis of osteoporosis. Fourteen jaws in 13 patients (11 females, 2 males; mean age: 68 yr) were subsequently subjected to oral implant treatment with a total of 70 implants (Brånemark System) of various designs. The mean follow-up period was 3 years and 4 months (range: 6 mo-11 yr).

RESULTS

Osteoporosis of either the spine, the hip, or both regions was diagnosed in 14 patients, and osteopenia was diagnosed in 2 patients. Two implants failed, and the overall implant survival rate at the end of the study period was 97.0% for maxillae and 97.3% for mandibles. The marginal bone resorption at the 1-year follow-up concurs with the outcome of other studies, irrespective of the preoperative bone texture present.

CONCLUSION

The outcome of the present study showed that implant placement in patients in whom the average bone density showed osteoporosis in both lumbar spine and hip as well as poor local bone texture may be successful over a period of many years.

Comparison of quantitative ultrasound and dual X-ray absorptiometry in estrogen-treated early postmenopausal women

Identifying individuals at risk of developing osteoporosis is important in order to initiate early treatment. Many new techniques have been proposed as alternatives for DXA-scanning. Some of these alternatives certainly have advantages, but none have so far been demonstrated to predict fractures better, or even to identify individuals at risk of osteoporosis as well as with the standard method. In this study, comprising a group of women from the Danish Osteoporosis Prevention Study, we wished to investigate whether a technique based on quantitative ultrasound (QUS) could identify individuals with low BMC/BMD as measured by dual X-ray absorptiometry (DXA). Furthermore, we wished to test whether the method could detect differences between untreated individuals and those treated with hormone replacement therapy. We found that QUS could detect differences between the treated and untreated groups, but it was unable to identify women with low BMD, although it might be able to identify persons not at risk of osteoporosis. Low QUS values should be followed by a regular DXA measurement to confirm the presence of osteoporosis.

Postmenopausal osteoporosis management

Osteoporosis is perhaps the widest-ranging social, physical, and economic impact of estrogen deficiency. Postmenopausal bone loss is the major determinant of osteoporosis. Osteoporotic risk can be determined by measuring bone mineral density using dual X-ray absorptiometry. The radiation free quantitative bone ultrasound is emerging in the assessment of bone structure giving reliable estimates of fracture risk. Diet and exercise are important in determining a woman's risks for osteoporosis. Hormone replacement therapy clearly decreases bone turnover and prevents postmenopausal bone loss and reduces fractures. Tibolone as well as raloxifene prevent bone loss and solid data demonstrate a reduction of vertebral fractures after raloxifene administration.

Does combining the results from multiple bone sites measured by a new quantitative ultrasound device improve discrimination of hip fracture?

There is a growing interest in the use of quantitative ultrasound (QUS) measurements as an alternative to current radiation-based bone densitometry techniques for the noninvasive assessment of fracture risk. While most of the commercialized ultrasound devices measure only single predefined peripheral skeletal sites, the Omnisense prototype (Sunlight Ltd., Israel) can be used on multiple bones, including the spinous processes. In this study, we examined the ability of speed of sound measured at the calcaneus, distal third and ultradistal radius, proximal third phalanx, metacarpal, capitate, patella, and the posterior process of the thoracic spine to differentiate subjects with hip fractures from normal controls. Seventy-nine postmenopausal Caucasian Israeli women who had sustained an atraumatic fracture of the proximal femur within the last 6 months were recruited from the local population (mean age 80 +/- 8.9 years). As controls, 295 postmenopausal Caucasian Israeli women without osteoporotic fractures were also included (mean age 70 +/- 8.7 years). Discrimination of hip fractures with QUS at all ultrasound sites was highly statistically significant (p < 0.01) (odds ratios [ORs] = 1.4-3.0; area under the ROC curve [AUC] 77-92%), except for the hand metacarpal. Distal radius and calcaneus measurements (ORs = 2.4 and 3.0) were the best discriminators of hip fracture patients from controls. Using a forward selective linear regression model, the discriminator values of combined assessment at two sites were investigated. There was moderate improvement in diagnostic value, but the best combination was the calcaneus with the distal radius, which improved the AUC by 3% and raised both the sensitivity and specificity to 94%. These data demonstrate the encouraging potential of improving discrimination of hip fracture by using multiple-site ultrasonic measurements.

Evaluation of quantitative ultrasound and dual X-Ray absorptiometry measurements in women with and without fractures

Dual X-ray absorptiometry (DXA) is considered a gold standard for bone measurements in the assessment of osteoporosis. Other techniques such as quantitative ultrasound (QUS) are promising to detect patients with osteoporosis-related fractures and to predict fracture risk. In this cross-sectional retrospective study, we analyzed the behavior of QUS and DXA measurements alone and in combination with regard to the presence of fractures in 320 women, 147 with nontraumatic fractures. Speed of sound (SOS), broadband ultrasound attenuation (BUA), and a third parameter derived from SOS and BUA called stiffness were measured at the calcaneus using an Achilles device (Lunar, Madison, WI). Lumbar (BMDL) and hip (BMDH( bone mineral density were measured by DXA (Hologic QDR 1000, Waltham, MA). Mean SOS, BUA, stiffness, and BMDL and BMDH were significantly lower in women with fractures compared with women without fractures. Logistic regression adjusted for age identified stiffness as the parameter most strongly associated with the presence of fracture: its sensitivity was 54% and specificity 70%. Hip BMD was second, with a sensitivity of 54% and a specificity of 69%. Combining QUS and DXA measurements did not improve the specificity nor the sensitivity. There was no difference in the odds ratios with regard to the technique that was chosen for bone assessment. In conclusion, these results suggest that low QUS measurements are associated with the presence of fractures in a way similar to DXA. In our study, the combination of QUS and DXA did not improve the discrimination of women with fractures.

Quantitative bone ultrasonometry in climacteric women

Quantitative bone ultrasound (QUS) measurement is an emerging technique in the assessment of osteoporosis risk. In this study, bone mineral density (BMD) (mg/cm2) of lumbar vertebrae, neck, Ward's triangle and trochanter were measured by DXA and the phalanx amplitude dependent speed of sound (AD-SOS) was measured by QUS in climacteric (n = 1025) women. The relationship between AD-SOS and BMD values at different skeletal sites was significant, even if the analysis showed poor correlation coefficients. These data seem to indicate that QUS can detect bone characteristics in addition to density. The AD-SOS was higher in premenopausal than in perimenopausal women. The AD-SOS further decreases in postmenopausal women without hormone replacement. The age at menopause is relevant for predicting the AD-SOS in the postmenopausal years. Conversely, the maintenance of a regular menstrual function is associated with higher AD-SOS. Thus, the early impairment and cessation of ovarian function can lead to an earlier and/or sharper decline in bone homeostasis that can be detected by QUS. In conclusion, AD-SOS is a valuable index in detecting menopausal bone loss, and could be used for the patient follow-up during menopausal transition and in therapeutic trials.