Search PubMed⌕ Search

Biomedical subjects

C C Glüer

Publications and source records attributed to C C Glüer.

At least 19 recordsLinked to original sources

Ibandronate treatment reverses glucocorticoid-induced loss of bone mineral density and strength in minipigs.

The Göttingen minipig is one of the few large animal models that show glucocorticoid (GC)-induced bone loss. We investigated whether GC-induced loss of bone mineral density (BMD) and bone strength in minipigs can be recovered by treatment with the bisphosphonate ibandronate (IBN). 40 primiparous sows were allocated to 4 groups when they were 30 months old: GC treatment for 8 months (GC8), for 15 months (GC15), GC treatment for 15 months plus IBN treatment for months 8-15 (GC&IBN), and a control group without GC treatment. Prednisolone was given at a daily oral dose of 1 mg/kg body weight for 8 weeks and thereafter 0.5 mg/kg body weight. IBN was administered intramuscularly and intermittently with an integral dose of 2.0 mg/kg body weight. BMD of the lumbar spine (L1-3) was assessed in vivo by Quantitative Computed Tomography (QCT) at months 0, 8, and 15. Blood and urine samples were obtained every 2-3 months. After sacrificing the animals lumbar vertebrae L4 were tested mechanically (Young's modulus and ultimate stress). Histomorphometry was performed on L2 and mineral content determined in ashed specimens of T12 and L4. In the GC&IBN group, the GC associated losses in BMD of -10.5%+/-1.9% (mean+/-standard error of the mean, p<0.001) during the first 8 months were more than recovered during the following 7 months of IBN treatment (+14.8%+/-1.2%, p<0.0001). This increase was significantly larger (p<0.0001) than the insignificant +2.1%+/-1.2% change in group GC15. At month 15, the difference between groups GC&IBN and GC15 was 22% (p<0.01) for BMD, 48% (p<0.05) for Young's modulus, and 31% (p<0.14) for ultimate stress; bone-specific alkaline phosphatase showed trends to lower values (p<0.2) while deoxypyridinoline was comparable. This minipig study demonstrates that GC-induced impairment of bone strength can be effectively and consistently treated by IBN. GC&IBN associated alterations in BMD and bone turnover markers can be monitored in vivo using QCT of the spine and by biochemical analyses, reflecting the changes in bone strength.

Absorptiometry, Photon↗

Influence of methods used in body composition analysis on the prediction of resting energy expenditure.

OBJECTIVE: There are considerable differences in published prediction algorithms for resting energy expenditure (REE) based on fat-free mass (FFM). The aim of the study was to investigate the influence of the methodology of body composition analysis on the prediction of REE from FFM. DESIGN: In a cross-sectional design measurements of REE and body composition were performed. SUBJECTS: The study population consisted of 50 men (age 37.1+/-15.1 years, body mass index (BMI) 25.9+/-4.1 kg/m2) and 54 women (age 35.3+/-15.4 years, BMI 25.5+/-4.4 kg/m2). INTERVENTIONS: REE was measured by indirect calorimetry and predicted by either FFM or body weight. Measurement of FFM was performed by methods based on a 2-compartment (2C)-model: skinfold (SF)-measurement, bioelectrical impedance analysis (BIA), Dual X-ray absorptiometry (DXA), air displacement plethysmography (ADP) and deuterium oxide dilution (D2O). A 4-compartment (4C)-model was used as a reference. RESULTS: When compared with the 4C-model, REE prediction from FFM obtained from the 2C methods were not significantly different. Intercepts of the regression equations of REE prediction by FFM differed from 1231 (FFM(ADP)) to 1645 kJ/24 h (FFM(SF)) and the slopes ranged between 100.3 kJ (FFM(SF)) and 108.1 kJ/FFM (kg) (FFM(ADP)). In a normal range of FFM, REE predicted from FFM by different methods showed only small differences. The variance in REE explained by FFM varied from 69% (FFM(BIA)) to 75% (FFM(DXA)) and was only 46% for body weight. CONCLUSION: Differences in slopes and intercepts of the regression lines between REE and FFM depended on the methods used for body composition analysis. However, the differences in prediction of REE are small and do not explain the large differences in the results obtained from published FFM-based REE prediction equations and therefore imply a population- and/or investigator specificity of algorithms for REE prediction.

Absorptiometry, Photon↗

Quality and performance measures in bone densitometry. Part 2: fracture risk.

INTRODUCTION: This is part 2 of a core chapter of the forthcoming Report on Bone Densitometry commissioned by the International Commission on Radiation Units (ICRU). It is written with the aim to review definitions of quantities and units used in bone densitometry research and to describe parameters and methods that can be used to compare and standardize densitometric equipment and measurements. Part 2 of this chapter contains the section on fracture risk. PERFORMANCE MEASURES IN THE ASSESSMENT OF FRACTURE RISK: Building on concepts of risk assessment, including risk ratios and odds ratios, we review statistical concepts commonly used in cross-sectional and prospective fracture studies. Performance measures are defined that allow a comparison of the ability of densitometry techniques to assess fracture risk. DISCUSSION: The methods of discriminant analysis, logistic regression, Poisson regression models, and the Cox proportional hazard model are presented and compared. In addition, statistical concepts to characterize risk for the individual patient are reviewed.

Aged↗

Relationship between risk factors and QUS in a European Population: The OPUS study.

There are many risk factors associated with low bone mineral density. Quantitative ultrasound (QUS) is a generally accepted method for measurement of bone and has been shown to be strongly associated with future fracture risk. The Osteoporosis and Ultrasound Study (OPUS) is a multi-centre European wide study examining 5 different QUS scanners (4 calcaneal, 1 finger device). The aim of this paper was to examine the relationship between risk factors (as assessed by questionnaire) and QUS measurements. 449 younger women (aged 20 to 39 years) and 2283 older women (aged 55 to 79 years) were included in this analysis. As expected, those with a self-reported previous fracture had lower QUS measurements than those without (P < 0.001). However, no significant difference was seen between those reporting a maternal hip fracture and those who did not report such an event. Differences were found for smokers vs. non-smokers for SOS but not for BUA measurements. Weight was positively correlated with all BUA variables but only with some SOS variables. We determined which risk factors were most strongly associated with QUS measurements by using step-wise multiple regression. Models for each QUS measurement were calculated, and the R2 values ranged from 0.18 to 0.28 for SOS, 0.27 to 0.32 for BUA and 0.31 to 0.42 for the finger QUS device. The most common risk factors across all models were age, use of hormone replacement therapy, self-reported previous fracture, self-reported diagnosis of osteoporosis, current weight, pulse rate and self-reported estimated height at age 20 years. We analysed relationships across the 5 centres and detected some geographical differences in the prevalence of the risk factors. In conclusion, similar relationships are seen with QUS measurements as are found for bone mineral density. However, the strength of the association is dependent on the type of QUS device and variable measured.

Adult↗

Reduction of sampling bias of odds ratios for vertebral fractures using propensity scores.

INTRODUCTION: Assessment of the predictive power of a newly introduced diagnostic technique with regard to fracture risk is frequently limited by the enormous costs and long time periods required for prospective studies. A preliminary estimate of predictive power usually relies on cross-sectional case-control studies in which bone measurements of normal and fractured subjects are compared. The measured discriminatory power is taken as an estimate of predictive power. Because of possible sample selection bias, study participants may have different bone mineral density (BMD) values, and fractured patients may have fractures of different severity levels. The same diagnostic techniques for the measured discriminatory power, expressed as odds ratios, will differ among studies with different patient and control populations. METHODS: In this paper, we propose a weighted logistic regression approach to adjust the odds ratio in order to reduce the effect of sampling bias. The weight is derived from age, deformity severity, BMD, and the interactions of these, using the propensity score theory and reference population data. RESULTS: Simulation examples using data from the Osteoporosis and Ultrasound Study (OPUS) demonstrate that such a procedure can effectively reduce the estimation bias of odds ratios introduced by sampling differences, such as for dual x-ray absorptiometry (DXA) scans of the spine and hip as well as various quantitative ultrasound techniques. The derived estimated odds ratios are substantially less biased, and the corresponding 95% confidence intervals contain the true odds ratios from the population data. CONCLUSIONS: We conclude that a statistical correction procedure based on propensity scores and weighted logistic regression can effectively reduce the effect of sampling bias on the odds ratios calculated from cross-sectional case-control studies. For a new diagnostic technique, hip BMD and deformity severity information are necessary and likely sufficient to derive the propensity scores required to adjust the measured standardized odds ratios.

Adult↗

German pediatric reference data for quantitative transverse transmission ultrasound of finger phalanges.

Quantitative ultrasound (QUS) of the finger phalanges is a useful tool in the assessment of disease- or age-related deterioration of bone. For studying the impact of juvenile diseases or growth disorders affecting the skeleton, a reference database for QUS parameters is needed. The aim of this study was to establish a calibrated reference database of parameters of transverse ultrasound transmission through juvenile finger phalanges. A total of 1328 children (650 females, 678 males; ages 3-17 years) were measured in Heidelberg and Kiel in order to establish a German reference database. Highly significant gender-specific correlations (p<0.0001) were found between the QUS parameters amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) versus age, body height and body mass index (BMI). For AD-SoS the correlation coefficients were R2 = 0.64 against age in males and R2 = 0.73 in females, R2 = 0.60 against body height in males and R2 = 0.68 in females, and R2 = 0.19 against BMI in males and R2 = 0.23 in females. For BTT the correlation coefficients were R2 = 0.74 against age in males and R2 = 0.79 in females, R2 = 0.75 against body height in males and R2 = 0.77 in females, and R2 = 0.32 against BMI in males and R2 = 0.35 in females. Age and height were the strongest determinants of QUS results. Gender-specific differences were observed in AD-SoS (significant for ages 11-14 years and for 150-170 cm body height) and in BTT (significant for ages 7 and 11-17 years and for 160-170 cm body height). Tables of QUS parameters versus age and height can serve as a basis for the evaluation of the impact of skeletal diseases or growth disorders on phalangeal QUS. Depending on the type of disease or growth disorder, measurement results can be compared with age- or height- specific reference data. In this way a simple and radiation-free assessment of juvenile skeletal disorders using quantitative ultrasound might be possible in the future.

Adolescent↗

Mechanical strength of the thoracolumbar spine in the elderly: prediction from in situ dual-energy X-ray absorptiometry, quantitative computed tomography (QCT), upper and lower limb peripheral QCT, and quantitative ultrasound.

The objective of this study was to compare the ability of clinically available densitometric measurement techniques for evaluating vertebral strength in elderly individuals. Measurements were related to experimentally determined failure strength in the thoracic and lumbar spine. In 127 specimens (82 women and 45 men, age 80 +/- 10 years), dual-energy X-ray absorptiometry (DXA) was performed at the lumbar spine, femur, radius, and total body, and peripheral-quantitative computed tomography (pQCT) at the distal radius, tibia, and femur under in situ conditions with intact soft tissues. Spinal QCT and calcaneal ultrasound parameters were performed ex situ in degassed specimens. Mechanical failure loads of thoracic vertebrae 6 and 10 (T-6 and -10), and lumbar vertebra 3 (L-3) were determined in axial compression on functional three-segment units. In situ anteroposterior DXA and QCT of the lumbar spine explained approximately 65% of the variability of thoracolumbar failure. A combination of cortical and trabecular density (QCT) provided the best prediction in the lumbar spine. However, this was not the case in the thoracic spine, for which lumbar cortical density (QCT) and DXA provided significantly better estimates than trabecular density (QCT). pQCT was significantly less correlated with the strength of lumbar and thoracic vertebrae (r(2) = 40%), but was equivalent to femoral or radial DXA. pQCT measurements in the lower limb showed no advantage over those at the distal radius. Ultrasound explained approximately 25% of the variability of vertebral failure strength and added independent information to spinal QCT, but not to spinal DXA. These experimental results advocate site-specific assessment of vertebral strength by either spinal DXA or QCT.

Absorptiometry, Photon↗

Assessment of phalangeal bone loss in patients with rheumatoid arthritis by quantitative ultrasound.

OBJECTIVE: Periarticular osteopenia is an early radiological sign of rheumatoid arthritis (RA). Quantitative ultrasound (QUS) devices have recently been shown to be useful for assessing osteoporosis. In this study the capability of a transportable and easy to use QUS device to detect skeletal impairment of the finger phalanges in patients with RA was investigated. METHODS: In a cross sectional study 83 women (30 controls, 29 with glucocorticosteroid (GC) treated RA, and 24 with GC treated vasculitis) were examined. QUS measurements were obtained at the metaphyses of the proximal phalanges II-V and directly at the proximal interphalangeal joints II-IV with a DBM Sonic 1200 (IGEA, Italy) QUS device. Amplitude dependent speed of sound (AD-SoS) was evaluated. In 23 of the patients with RA, hand radiographs were evaluated. RESULTS: Significant differences between patients with RA and the other groups were found for AD-SoS at both measurement sites. Compared with age matched controls, the AD-SoS of patients with RA was lowered by two and three standard deviations at the metaphysis and joint, respectively. Fingers of patients with RA without erosions (Larsen score 0-I) already had significantly decreased QUS values, which deteriorated further with the development of erosions (Larsen II-V). CONCLUSION: This study indicates that QUS is sensitive to phalangeal periarticular bone loss in RA. QUS is a quick, simple, and inexpensive method free of ionising radiation that appears to be suited to detection of early stages of periarticular bone loss. Its clinical use in the assessment of early RA should be further evaluated in prospective studies.

Adult↗

An update on the diagnosis and assessment of osteoporosis with densitometry. Committee of Scientific Advisors, International Osteoporosis Foundation.

In 1994 the WHO proposed guidelines for the diagnosis of osteoporosis based on measurement of bone mineral density. They have been widely used for epidemiological studies, clinical research and for treatment strategies. Despite the widespread acceptance of the diagnostic criteria, several problems remain with their use. Uncertainties concern the optimal site for assessment, thresholds for men and diagnostic inaccuracies at different sites. In addition, the development of many new technologies to assess the amount or quality of bone poses problems in placing these new tools within a diagnostic and assessment setting. This review considers the recent literature that has highlighted the strengths and weaknesses of diagnostic thresholds and their use in the assessment of fracture risk, and makes recommendations for actions to resolve these difficulties.

Absorptiometry, Photon↗

Assessment of the geometry of human finger phalanges using quantitative ultrasound in vivo.

Quantitative Ultrasound (QUS) methods have been shown to be useful in the assessment of bone status. Nevertheless, ultrasound transmission depends on a variety of skeletal parameters, and a detailed understanding of ultrasound propagation through bone is important for the accurate interpretation of QUS results. In this study we wanted to elucidate the pathways of an ultrasound wave through finger phalanges and determine correlations between geometric and QUS parameters. Phalanges of a subject group were measured using QUS and magnetic resonance imaging (MRI). MRI was used for the derivation of the geometric parameters. Similar assessments were performed on cylindrical tubes and with a simulation program. New parameters related to speed of sound (SOS) and amplitude of the wave (A2P) were calculated. Strong correlations between QUS parameters and morphologic cross-sectional areas were observed in vivo and in phantoms. Similar correlations could be found in the calculations using the simulation software. Cross-sectional cortical area, medullary canal area and relative cortical area could be calculated from the QUS parameters (subjects: R2 = 0.71 for cortical area, R2 = 0.45 for medullary canal area and R2 = 0.61 for relative cortical area; phantoms: R2 = 0.98 for cortical area, R2 = 0.78 for medullary canal area and R2 = 0.77 for relative cortical area). In vivo, phantom and simulation results consistently showed that SOS was correlated with cortical area but not with medullary canal area while the opposite was found for A2P. Pathways of the ultrasound wave through solid cortical bone and the medullary canal could be identified and the propagation of the wave could be depicted. These results help to interpret QUS findings and provide information that may be helpful in improving the performance of QUS.

Adult↗

Evaluation of water content by spatially resolved transverse relaxation times of human articular cartilage.

Non-invasive assessment of cartilage properties, specifically water content, could prove helpful in the diagnosis of early degenerative joint diseases. Transverse relaxation times T(2) of human articular cartilage (34 cartilage slices of three donors) were measured on a pixel-by-pixel basis in a clinical whole body MR system in vitro. In vivo feasibility to measure quantitative T(2) maps was shown for human patellar cartilage. The relaxation times of cartilage with collagen in the radial zone oriented perpendicular to the magnetic field increased from approximately 10 ms near the bone to approximately 60 ms near the articular surface. Cartilage water content of the tibial plateau and femoral condyles could be determined from the correlation with T(2) (R(2) = 0.71) with an error of approximately 2 wt.%. In vivo, directional variation would need to be considered. If confirmed in vivo, T(2) measurements could potentially serve as a non-invasive tool for the evaluation of the status and distribution of water content in articular cartilage.

Adult↗

The use of bone densitometry in clinical practice.

Bone densitometry is an established method for the assessment of osteoporosis as, according to the definition of osteoporosis, an accurate determination of the level of bone mass is central to the diagnostic assessment of osteoporosis. The diversity of different bone densitometry techniques, however, needs to be acknowledged. The World Health Organization criteria of osteoporosis should not be used for peripheral measurements, and their application to subject groups other than white women is still controversial. A large variety of bone densitometry and quantitative ultrasound techniques can be used for fracture risk assessment. Their results should be interpreted in the context of other clinical examinations and can then be used in making treatment decisions. For monitoring purposes, the ratio of response rate and long-term precision error determines longitudinal sensitivity. For all of these applications, careful quality assurance procedures need to be implemented. If applied in a responsible fashion, bone densitometry represents a powerful approach that is indispensable for the assessment of osteoporosis.

Bone Density↗

Phalangeal osteosonogrammetry study: age-related changes, diagnostic sensitivity, and discrimination power. The Phalangeal Osteosonogrammetry Study Group.

Phalangeal osteosonogrammetry was introduced as a method for bone tissue investigation in 1992. It is based on the measure of the velocity of ultrasound (amplitude-dependent speed of sound [AD-SoS]) and on the interpretation of the characteristics of the ultrasound signal. In this study we have collected a database of 10,115 subjects to evaluate the performance of AD-SoS and to develop a parameter that is able to quantify the signal characteristics: ultrasound bone profile index (UBPI). The database only includes females of which 4.5% had documented vertebral osteoporotic fractures, 16% lumbar spine dual X-ray absorptiometry (DXA), and 6% hip DXA. The analysis of the ultrasound signal has shown that with aging the UBPI, first wave amplitude (FWA), and signal dynamics (SDy) follow a trend that is different from the one observed for AD-SoS; that is, there is no increase during childhood. In the whole population, the risk of fracture per SD decrease for AD-SOS was odds ratio (OR) 1.71 (CI, 1.58-1.84). The AD-SoS in fractured subjects was significantly lower than in a group of age-matched nonfractured subjects (p < 0.0001). In a small cohort of hip-fractured patients UBPI proved to be lower than in a control age-matched group (p < 0.0001). When the World Health Organization (WHO) working group criteria were applied to this population to identify the T score value for osteoporosis, for AD-SoS we found a T score of -3.2 and for UBPI we found a T score of -3.14. Sixty-six percent of vertebral fractures were below the AD-SoS -3.2 T score and 62% were below UBPI -3.14. We observed the highest incidence of fractures (63.6%) among subjects with AD-SoS who had both DXA T score values below the threshold. We conclude from this study that ultrasound investigation at the hand phalanges is a valid methodology for osteoporosis assessment. It has been possible to quantify signal changes by means of UBPI, a parameter that will improve the possibility of investigating bone structure.

Adult↗

A new method for quantitative ultrasound measurements at multiple skeletal sites: first results of precision and fracture discrimination.

We investigated a new multisite quantitative ultrasound device that measures the acoustic velocity in axial transmission mode along the cortex. Using a prototype of the Omnisense (Sunlight Ultrasound Technologies, Rehovot, Israel), we tested the performance of this instrument at four sites of the skeleton: radius, ulna, metacarpal, and phalanx. Intraobserver (interobserver) precision errors ranged from 0.2% to 0.3% (0.3% to 0.7%) for triplicate measurements with repositioning. Fracture discrimination was tested by comparing a group of 34 women who had previously suffered a fracture of the hip, spine, ankle, or forearm to a group of 28 healthy women who had not suffered a fracture. Age-adjusted standardized odds ratios ranged from 1.6 to 4.5. Except for the ulna the sites showed a significant fracture discrimination (p < 0.01). The areas under the receiver operating curves (ROC) curves were from 0.88 to 0.89 for radius, metacarpal, and phalanx. A combination of the results from the three sites showed a significant increase of the ROC area to 0.95 (p < 0. 05). Our results show promising performance of this new device. The ability to measure a large variety of sites and the potential to combine these measurements are promising with regard to optimizing fracture risk assessment.

Aged↗

[Quantitative ultrasonic diagnosis for the assessment of osteoporosis].

In recent years Quantitative Ultrasound (QUS) approaches have increasingly been used for the assessment of osteoporosis. Extensive study results exist for the estimation of osteoporotic fracture risk. Also, results exist for the analysis of properties which characterize osteoporosis--low bone mass and deterioration of bone architecture. However, the existence of different methods, devices and parameters has to be taken into account. Moreover, the status of the evaluation is different for each type of device. Measures of quality assurance and in-depth knowledge about limitations of the approach are of substantial importance for clinical use. Because of the lack of ionising radiation and their lower cost, QUS approaches--if used appropriately--can play an important role in the assessment of osteoporotic fracture risk.

Bone Density↗

Reduction of vertebral fracture risk in postmenopausal women with osteoporosis treated with raloxifene: results from a 3-year randomized clinical trial. Multiple Outcomes of Raloxifene Evaluation (MORE) Investigators.

CONTEXT: Raloxifene hydrochloride, a selective estrogen receptor modulator, prevents bone loss in postmenopausal women, but whether it reduces fracture risk in these women is not known. OBJECTIVE: To determine the effect of raloxifene therapy on risk of vertebral and nonvertebral fractures. DESIGN: The Multiple Outcomes of Raloxifene Evaluation (MORE) study, a multicenter, randomized, blinded, placebo-controlled trial. SETTING AND PARTICIPANTS: A total of 7705 women aged 31 to 80 years in 25 countries who had been postmenopausal for at least 2 years and who met World Health Organization criteria for having osteoporosis. The study began in 1994 and had up to 36 months of follow-up for primary efficacy measurements and nonserious adverse events and up to 40 months of follow-up for serious adverse events. INTERVENTIONS: Participants were randomized to 60 mg/d or 120 mg/d of raloxifene or to identically appearing placebo pills; in addition, all women received supplemental calcium and cholecalciferol. MAIN OUTCOME MEASURES: Incident vertebral fracture was determined radiographically at baseline and at scheduled 24- and 36-month visits. Nonvertebral fracture was ascertained by interview at 6-month-interim visits. Bone mineral density was determined annually by dual-energy x-ray absorptiometry. RESULTS: At 36 months of the evaluable radiographs in 6828 women, 503 (7.4%) had at least 1 new vertebral fracture, including 10.1% of women receiving placebo, 6.6% of those receiving 60 mg/d of raloxifene, and 5.4% of those receiving 120 mg/d of raloxifene. Risk of vertebral fracture was reduced in both study groups receiving raloxifene (for 60-mg/d group: relative risk [RR], 0.7; 95% confidence interval [CI], 0.5-0.8; for 120-mg/d group: RR, 0.5; 95% CI, 0.4-0.7). Frequency of vertebral fracture was reduced both in women who did and did not have prevalent fracture. Risk of nonvertebral fracture for raloxifene vs placebo did not differ significantly (RR, 0.9; 95% CI, 0.8-1.1 for both raloxifene groups combined). Compared with placebo, raloxifene increased bone mineral density in the femoral neck by 2.1 % (60 mg) and 2.4% (120 mg) and in the spine by 2.6% (60 mg) and 2.7% (120 mg) P<0.001 for all comparisons). Women receiving raloxifene had increased risk of venous thromboembolus vs placebo (RR, 3.1; 95% CI, 1.5-6.2). Raloxifene did not cause vaginal bleeding or breast pain and was associated with a lower incidence of breast cancer. CONCLUSIONS: In postmenopausal women with osteoporosis, raloxifene increases bone mineral density in the spine and femoral neck and reduces risk of vertebral fracture.

Adult↗

[Quantitative ultrasound. State of the art 1999].

In recent years Quantitative Ultrasound (QUS) approaches have increasingly been used for the assessment of osteoporosis. The development of new technologies has accelerated, and today a number of different devices are commercially available. For a balanced evaluation of the approaches one needs to recognise two issues: There are different applications for QUS, and there are different QUS approaches and devices. Regarding the applications, today the main area for use of QUS approaches is the assessment of a fracture risk. For use in monitoring and diagnosis, further advances and studies are required. Regarding the various approaches, one needs to recognise the differences between the measurement parameters Speed Of Sound (SOS) and Broadband Ultrasound Attenuation (BUA), the different measurement sites and the different technologies employed. Moreover, some of the earlier devices are very well validated whereas newer machines may feature more advanced technology--which, however, needs to be tested and validated. Whatever the choice of a device will be, adequate and regularly performed measures for quality assurance and in-depth knowledge on the general and device specific limitations of the approach are of substantial importance. When used appropriately, QUS devices can play an important role in the assessment of osteoporosis.

Humans↗