Quantitative ultrasound bone measurements: normal values and comparison with bone mineral density by dual X-ray absorptiometry

In Vivo Assessment of Bone Quality Without X-rays

PURPOSE OF REVIEW

This review summarizes recent advances in the assessment of bone quality using non-X-ray techniques.

RECENT FINDINGS

Quantitative ultrasound (QUS) provides multiple measurements of bone characteristics based on the propagation of sound through bone, the attenuation of that sound, and different processing techniques. QUS parameters and model predictions based on backscattered signals can discriminate non-fracture from fracture cases with accuracy comparable to standard bone mineral density (BMD). With advances in magnetic resonance imaging (MRI), bound water and pore water, or a porosity index, can be quantified in several long bones in vivo. Since such imaging-derived measurements correlate with the fracture resistance of bone, they potentially provide new BMD-independent predictors of fracture risk. While numerous measurements of mineral, organic matrix, and bound water by Raman spectroscopy correlate with the strength and toughness of cortical bone, the clinical assessment of person's bone quality using spatially offset Raman spectroscopy (SORS) requires advanced spectral processing techniques that minimize contaminating signals from fat, skin, and blood. Limiting exposure of patients to ionizing radiation, QUS, MRI, and SORS has the potential to improve the assessment of fracture risk and track changes of new therapies that target bone matrix and micro-structure.

The Effects of Claw Health and Bone Mineral Density on Lameness in Duroc Boars

To investigate the effects of claw lesion types and bone mineral density on lameness in boars, the data of claw lesion score, gait score, and bone mineral density, measured by a Miniomin ultrasound bone densitometer, were collected from a total of 739 Duroc boars. Firstly, we discovered that the prevalence of claw lesions was as high as 95.26% in boars. The percentage of lameness of boars with SWE was higher than those with other claw lesions. Meanwhile, the results showed that the probability of lameness was higher in boars with lower bone mineral density (p < 0.05). Logistic regression models, including variables of boar age, body weight, serum mineral level, and housing type, were used to identify the influencing factors of bone mineral density in this study. The results found that bone mineral density increases with age before reaching a maximum value at 43 months of age, and begins to decrease after 43 months of age. Elevated serum Ca levels were significantly associated with an increase in bone mineral density (p < 0.05). Aside from the above findings, we also made an interesting discovery that boars in the individual pen model significantly increased bone mineral density compared to those in the individual stall model. In conclusion, claw lesions and bone mineral density were significantly associated with lameness. Age, serum Ca, and housing type are the potential influencing factors for bone mineral density in boars.

Bone Strength of the Calcaneus Is Associated with Dietary Calcium Intake in Older Japanese Men, but Not Women

The relationship between calcium intake and bone strength in older Asian individuals, including Japanese, is controversial; therefore, we herein investigated this relationship in older Japanese populations. We performed a cross-sectional analysis of 314 participants older than 65 years who voluntarily participated in a medical examination and responded to questionnaires. The osteo-sono assessment index (OSI) measured at the right calcaneus using a quantitative ultrasonic device was used as an indicator of bone strength. The daily dietary intake of calcium was assessed using a brief-type self-administered diet history questionnaire. A two-way analysis of covariance revealed a significant interaction between sex and calcium intake on the OSI (p < 0.01). A multiple regression analysis showed a positive correlation between calcium intake and the OSI in males (p < 0.01), but not females (p = 0.27). In females, grip strength divided by body weight positively correlated with the OSI (p = 0.04). The present results suggest that a higher calcium intake contributes to bone strength in older Japanese males. Although a higher grip strength may contribute to bone strength in females, the potential of estrogen as a confounding factor needs to be considered.

Genome-wide association study of bone mineral density trait among three pig breeds

Leg weakness (LW) issues are a great concern for pig breeding industry. And it also has a serious impact on animal welfare. To dissect the genetic architecture of limb-and-hoof firmness in commercial pigs, a genome-wide association study was conducted on bone mineral density (BMD) in three sow populations, including Duroc, Landrace and Yorkshire. The BMD data were obtained by ultrasound technology from 812 pigs (including Duroc 115, Landrace 243 and Yorkshire 454). In addition, all pigs were genotyped using genome-by-sequencing and a total of 224 162 single-nucleotide polymorphisms (SNPs) were obtained. After quality control, 218 141 SNPs were used for subsequent genome-wide association analysis. Nine significant associations were identified on chromosomes 3, 5, 6, 7, 9, 10, 12 and 18 that passed Bonferroni correction threshold of 0.05/(total SNP numbers). The most significant locus that associated with BMD (P value = 1.92e-14) was detected at approximately 41.7 Mb on SSC6 (SSC stands for Sus scrofa chromosome). CUL7, PTK7, SRF, VEGFA, RHEB, PRKAR1A and TPO that are located near the lead SNP of significant loci were highlighted as functionally plausible candidate genes for sow limb-and-hoof firmness. Moreover, we also applied a new method to measure the BMD data of pigs by ultrasound technology. The results provide an insight into the genetic architecture of LW and can also help to improve animal welfare in pigs.

Weight loss since early adulthood, later life risk of fracture hospitalizations, and bone mineral density: a prospective cohort study of 0.5 million Chinese adults

In a Chinese population from both urban and rural areas, weight loss of ≥ 5 kg from early adulthood to midlife was associated with a higher risk of hip fracture and lower BMD in later life.

INTRODUCTION

This study investigates the association of the long-term weight loss from young adulthood through the middle ages with the subsequent 10-year risk of hospitalized fracture and calcaneus bone mineral density (BMD).

METHODS

China Kadoorie Biobank (CKB) was established during 2004-2008 in ten areas across China. Weight at age 25 years was self-reported at baseline, and weight at baseline and resurvey was measured by the calibrated equipment. Outcomes were hospitalized fracture during follow-up and calcaneus BMD measured at resurvey. Analysis for fracture risk included 411,812 participants who were free of fracture in the last 5 years before baseline, cancer, or stroke at any time before baseline. Analysis for BMD included 21,453 participants who participated in the resurvey of 2013-2014 with the same exclusion criteria as above.

RESULTS

The mean age was 50.8 at baseline and 58.4 at resurvey. Median weight change from age 25 to baseline was 4.4 kg, with 20.7% losing weight and 58.5% gaining weight. During a median follow-up of 10.1 years, we documented 13,065 cases of first diagnosed fracture hospitalizations, including 1222 hip fracture. Compared with participants whose weight was stable (± 2.4 kg), the adjusted hazard ratios (95% CIs) for those with weight loss of ≥ 5.0 kg from age 25 to baseline was 1.39 (1.17 to 1.66) for hip fracture. Weight loss was not associated with fracture risk at other sites. Those with weight loss from age 25 to resurvey had the lowest BMD measures, with β (95% CIs) of - 4.52 (- 5.08 to - 3.96) for broadband ultrasound attenuation (BUA), - 4.83 (- 6.98, - 2.67) for speed of sound (SOS), and - 4.36 (- 5.22, - 3.49) for stiffness index (SI).

CONCLUSIONS

Weight loss from early adulthood to midlife was associated with a higher risk of hip fracture and lower BMD in later life.

Vitamin K deficiency, evaluated with higher serum ucOC, was correlated with poor bone status in women

BACKGROUND

An increase in serum undercarboxylated osteocalcin concentrations suggests vitamin K deficiency. Clinical intervention studies suggested that the vitamin K supplementation might contribute to preventing bone loss in postmenopausal women. Evidence on the relationship between serum undercarboxylated osteocalcin (ucOC) levels and bone parameters of quantitative ultrasound (QUS) is limited. We examined the correlation between serum ucOC concentrations and bone status as measured by QUS among middle-aged and older Japanese men and women.

METHODS

The subjects were community-dwelling men (n = 358) and women (n = 503) aged ≥ 40 years in Japan. Heel QUS parameters, including the stiffness index, speed of sound, and broadband ultrasound attenuation, were measured. Serum ucOC concentrations were measured by electrochemiluminescence immunoassay. Grip strength was measured in the dominant hand. Information on alcohol drinking, current smoking, exercise, and menopause in women was collected.

RESULTS

Serum ucOC concentrations were significantly associated with age in both sexes. Serum ucOC concentrations in men were higher at ≥ 80 years than those in the age groups of 40-49, 50-59, and 60-69 years. Serum ucOC concentrations in women were higher in the age groups of 50-59 and 60-69 years than those at 40-49 years. Partial correlation analysis adjusting for covariates (age, body mass index, grip strength, alcohol drinking, current smoking, and exercise in men; age, body mass index, grip strength, alcohol drinking, current smoking, exercise, and menopause in women) showed that serum ucOC concentrations were negatively significantly correlated with all QUS parameters in women. Serum ucOC concentrations were not correlated with them in men.

CONCLUSIONS

Vitamin K deficiency, evaluated with higher serum ucOC, was correlated with poor bone status in women.

Tea consumption and bone health in Chinese adults: a population-based study

Tea is a worldwide drink with controversial effect on bone health. The sex-specific associations are unrevealed among general population. This study showed that prolonged moderate tea consumption benefited bone health in women, while no additional benefit with stronger tea. However, tea consumption was not associated with bone health in men.

INTRODUCTION

Tea consumption has been shown a potentially beneficial effect on bone health in postmenopausal women. However, little is known about such association in men, and whether stronger tea instead harms bone health due to elevated urinary excretion of calcium associated with caffeine in the tea. The aim of this study was to examine the association between various metrics of tea consumption and bone health.

METHODS

The present study included 20,643 participants from the China Kadoorie Biobank (CKB), who have finished both baseline survey (2004-2008) and a re-survey (2013-2014). They were aged 38-86 years at re-survey. Tea consumption was self-reported at both baseline and re-survey. Bone mineral density (BMD) was measured using calcaneal quantitative ultrasound once at re-survey.

RESULTS

Compared with non-consumers, prolonged weekly tea consumers in women was associated with higher calcaneus BMD measures, with β (95% CI) of 0.98 (0.22, 1.74) for BUA, 4.68 (1.74, 7.61) for SOS, and 1.95 (0.81, 3.10) for SI. Among prolonged weekly tea consumers, no linear increase in BMD measures with the amount of tea leaves added was observed. The SOS and SI were higher in consumers with tea leaves 3.0-5.9 g/day than in those with < 3.0 g/day, but were reduced to non-significant for those with ≥ 6.0 g/day. Tea consumption was not associated with calcaneus BMD measures in men.

CONCLUSION

Prolonged moderate tea consumption benefited bone health in women but not in men. For stronger tea consumption with more tea leaves added, neither benefit nor harm to bone health was observed.

The effects of milk intake and whole-body vibration exercise on bone mineral density in elderly women in nursing homes

[Purpose] This study was designed to investigate the effects of lactose-free milk intake and whole-body vibration exercises on bone density in elderly female nursing home residents who had difficulty exercising outdoors and had not consumed milk. [Subjects and Methods] Twenty seven elderly women aged 70 or older from 3 nursing homes located in Incheon, Korea participated in the study. The experimental group (n=13) carried out whole-body vibration exercises and drank lactose-free milk, while the control group (n=14) continued to live their ordinary nursing home lives. Weight, BMI, T-scores, and Z-scores were compared between the experimental and control groups after 12 weeks. [Results] The comparison of changes in weight and BMI in the control group before and after the 12-week experiment found no statistically significant differences. However, bone mineral density was significantly different, with the T-score significantly decreasing from -2.99 to -3.48 and the Z-score decreasing from -1.87 to -2.58. The other comparisons of physical changes in the control group before and after the 12-week experiment found no statistical significance. [Conclusion] The results indicate that regular consumption of lactose-free milk and performing whole-body vibration exercises can delay the progression of bone density loss in older adults in nursing homes; adequate exercise and calcium intake could eventually help prevent fractures.

Quantitative ultrasound measurements of bone quality in female adolescents with idiopathic scoliosis compared to normal controls

OBJECTIVE

The aims of this study were to compare the speed-of-sound (SOS) between adolescent idiopathic scoliosis (AIS) patients and controls using quantitative ultrasound examination and to further analyze the relationship between the SOS and curve type, curve magnitude, maturation status and Risser's sign in AIS patients compared to controls.

METHODS

Seventy-eight female AIS patients and 58 healthy female controls 10 to 16 years of age were recruited to participate. Quantitative ultrasound measurements were performed at the non-dominant distal end of the radius. The standard method for estimating the SOS and z-score was used. Comparisons were made between the SOS values and z-score in AIS patients and age-matched Asian adolescents.

RESULTS

The SOS values of the patients were significantly lower than the controls (P < .01). The percentage of cases with low bone quality was 25% in the entire AIS sample. The prevalence of low bone quality in AIS patients was 20.5%. However, there were no correlations between the SOS and types of scoliosis (P > .05). The SOS values among different severity groups were significant, particularly between the 10° to 19° and 20° to 39° groups as well as between 10° to 19° and ≥40° groups. However, there was no significant correlation between the SOS and Cobb angles. Significant correlations were also found between the pre- and post-menarchy status in patients. There was a significant difference in the SOS values for different Rissers' signs (P < .05).

CONCLUSIONS

Compared to nonscoliotic controls, subjects with AIS had a generally lower SOS, indicating lower bone quality. The age, Risser's sign, or maturation status, may have an effect on the bone quality; however, the curve type and magnitude do not affect the bone quality. The results of this study indicate that slower bone maturation may affect the bone quality in adolescents with AIS.

Measurement properties of radial and tibial speed of sound for screening bone fragility in 10- to 12-year-old boys and girls

The objective of this study was to analyze measurement properties of the radial and tibial speed of sound (SoS) evaluated by quantitative ultrasound (QUS) for screening bone fragility. Bone fragility was defined as low whole body less head bone mineral density (WBLH BMD) measured by DXA (first tertile, 95% CI -1.1 to -0.9) and as past fractures evaluated by questionnaire. The sample included 319 nonobese boys and girls, ages 10-12 yr. All bone variables were standardized. The results revealed concordance coefficient correlations between WBLH BMD and radial and tibial SoS of 0.129 and 0.038, respectively. The regression lines between DXA and QUS variables were different from the identity lines. Cross-classification analysis by Kappa statistic showed that only 34% and 36% of the 113 participants categorized in the first tertile of WBLH BMD were also categorized in the first tertile of tibial and radial SoS, correspondingly. Logistic regression with gender and maturity adjustments demonstrates that radial SoS was the single significant variable in predicting OR for identifying participants with past fractures. In conclusion, the radial QUS revealed itself to be a valuable tool for screening bone fragility in youth of 10-12 yr, despite the absence of agreement with DXA WBLH BMD.

Association between gait speed and bone strength in community-dwelling postmenopausal Japanese women

OBJECTIVES

It is unclear whether gait speed can be used to predict bone status or to diagnose osteopenia or osteoporosis. The aim of our study was to determine whether the measurement of physical performance predicts bone strength in community-dwelling postmenopausal Japanese women.

METHODS

We measured speed of sound (SOS), weight bearing index (WBI), maximum or usual gait speed, step length of each gait, single leg balance time with or without eyes closed, and grip strength among 1,061 postmenopausal women (mean age ± standard deviation 68 ± 8 years).

RESULTS

After adjustments for age and body mass index, SOS was associated with maximum or usual gait speed and with step length during maximum speed gait, but not with WBI, grip strength, single-leg balance time with or without eyes closed, or step-length time during usual gait speed. When subjects were divided into quartile groups based on WBI (a marker of lower extremity strength), significant associations between usual or maximum gait speed and SOS were found only in the lowest and second lowest groups (first and second quartiles). Finally, analysis of sensitivity and specificity at various cut-off points of maximum gait speed to predict decreased SOS showed relatively high specificity compared with the corresponding sensitivity among those with low gait speed.

CONCLUSIONS

Maximum gait speed together with WBI may be a useful and specific test to predict bone status in postmenopausal older women.

Bone quantitative ultrasound measurements in relation to the metabolic syndrome and type 2 diabetes mellitus in a cohort of elderly subjects at high risk of cardiovascular disease from the PREDIMED study

OBJECTIVE

The aim of this study is to determine whether metabolic syndrome, its individual components, or the presence of type 2 diabetes mellitus are associated with a better bone status estimated by quantitative ultrasound at the calcaneus.

DESIGN

Cross-sectional study.

SETTING

Outpatient clinics.

PARTICIPANTS

251 elderly subjects at high cardiovascular risk from the PREDIMED study were included.

MEASUREMENTS

MetS was defined according to the ATPIII diagnosis criteria. Calcaneus quantitative ultrasound (QUS) assessment was performed using the Sahara system.

RESULTS

Subjects with MetS showed significantly lower 24-hour urinary deoxypyridinoline/creatinine (u-DPD/creatinine) levels and higher broadband ultrasound attenuation, and a tendency to higher bone mineral density (BMD) and quantitative ultrasound index (QUI) than their counterparts. Individuals with type 2 diabetes mellitus (T2DM) showed a significantly higher bone broadband ultrasound attenuation (BUA) and QUI than their non-diabetic counterparts, despite they shown a higher prevalence of osteoporotic fractures. Multiple linear regression analyses showed that quantitative ultrasound parameters were positively associated with the metabolic syndrome and T2DM. Of the bone biochemical markers, only u-DPD/creatinine was related to MetS, abdominal obesity, hypertriglyceridemia component of the MetS, and the number of features that define the MetS.

CONCLUSION

This is the first study showing a positive association between MetS or T2DM with better bone status and lower bone resorption markers measured by quantitative ultrasound. Our results suggest that metabolic abnormalities have a positive effect on healthy bone in elderly subjects at high risk of cardiovascular disease.

Dietary vitamin K intake is associated with bone quantitative ultrasound measurements but not with bone peripheral biochemical markers in elderly men and women

BACKGROUND

Vitamin K may have a protective role against bone loss and osteoporotic fractures associated to aging, although data in humans are inconsistent and the mechanisms involved are still unknown. The main objective of the study was to assess the associations between vitamin K intake, bone density, bone structure quality and biochemical bone metabolism markers in elderly subjects. We also analyzed the relationship between changes in vitamin K intake and the evolution of bone quality markers after two years of follow-up.

METHODS

Cross-sectional analysis was carried out on 365 elderly subjects, 200 of whom were also included in a 2-year longitudinal follow-up study. Usual dietary intakes were assessed using a semi-quantitative 137-item food frequency questionnaire (FFQ). Vitamin K intake was estimated using the USDA database. Bone biochemical markers were measured in a subset of 125 subjects. Quantitative ultrasound assessment (QUS) was performed at the calcaneus to estimate bone mineral density (BMD), speed of sound (SOS), broadband ultrasound attenuation (BUA) and the quantitative ultrasound index (QUI).

RESULTS

Dietary intake of vitamin K was significantly associated with higher BMD and better QUS. No significant associations were found between vitamin K intake and bone biochemical markers. Those subjects who increased their vitamin K intake showed a lower loss of BMD, a lower decrease in SOS and a nonsignificant increase in BUA.

CONCLUSIONS

High dietary vitamin K intake was associated with superior bone properties. Moreover, an increase in dietary vitamin K was significantly related to lower losses of bone mineral density and smaller increases in the porosity and elasticity attributed to aging, which helps to explain the previously described protective effect of vitamin K intake against osteoporotic fractures.

Normative Data for Quantitative Calcaneal Ultrasound in Asian Children

Introduction: Dual energy X-ray absorptiometry (DEXA) is currently the gold standard for the assessment of bone mineral density. Quantitative ultrasound (QUS), on the other hand, is a radiation-free alternative for the assessment of bone strength in the paediatric population. Establishing normative data for bone strength specific to the population would allow identification of children at risk of osteoporosis as a consequence of disease and its treatment. This cross-sectional study aims to establish the normal reference range for calcaneal broadband ultrasound attenuation (BUA) measurements in normal Singaporean children aged 6 to 12 years. Materials and Methods: Healthy Singaporean children were randomly selected from 11 primary schools for the assessment of calcaneal BUA, using the paediatric Contact Ultrasonic Bone Analyzer (CUBA, McCue Plc, Compton, Winchester, England). The height, weight, body mass index and BUA measurements for each age group and gender were expressed as the mean ± SD. One-way ANOVA was used to compare the mean calcaneal BUA by age and gender of Singaporean children with that of children from the United Kingdom, Turkey and Taiwan. Results: A total of 750 healthy Singaporean children (417 males and 333 females) aged 6 to 12 years from 11 primary schools were enrolled. The calcaneal BUA values of Turkish and white British children were not statistically different from this Singaporean cohort. However, the Singaporean calcaneal BUA measurements were significantly higher compared to the Taiwanese children. Conclusion: This study provides the first normal reference data to evaluate bone strength in Singaporean children using the paediatric Contact Ultrasonic Bone Analyzer. Keywords: Bone strength, Osteoporosis, Paediatrics

Influence of Lifestyle Factors on Quantitative Heel Ultrasound Measurements in Middle-Aged and Elderly Men

We examined the distribution of quantitative heel ultrasound (QUS) parameters in population samples of European men and looked at the influence of lifestyle factors on the occurrence of these parameters. Men aged between 40 and 79 years were recruited from eight European centers and invited to attend for an interviewer-assisted questionnaire, assessment of physical performance, and quantitative ultrasound (QUS) of the calcaneus (Hologic; Sahara). The relationships between QUS parameters and lifestyle variables were assessed using linear regression with adjustments for age, center, and weight. Three thousand two hundred fifty-eight men, mean age 60.0 years, were included in the analysis. A higher PASE score (upper vs. lower tertile) was associated with a higher BUA (β coefficient = 2.44 dB/Mhz), SOS (β = 6.83 m/s), and QUI (β = 3.87). Compared to those who were inactive, those who walked or cycled more than an hour per day had a higher BUA (β = 3.71 dB/Mhz), SOS (β = 6.97 m/s), and QUI (β = 4.50). A longer time to walk 50 ft was linked with a lower BUA (β = -0.62 dB/Mhz), SOS (β = -1.06 m/s), and QUI (β = -0.69). Smoking was associated with a reduction in BUA, SOS, and QUI. There was a U-shaped association with frequency of alcohol consumption. Modification of lifestyle, including increasing physical activity and stopping smoking, may help optimize bone strength and reduce the risk of fracture in middle-aged and elderly European men.

Bone stiffness in men with type 2 diabetes mellitus

Osteoporosis in elderly men as well as women is increasingly recognized, and patients with type 2 diabetes mellitus have higher risk of fracture than nondiabetic subjects. The aim of the present study was to investigate the relationship between bone stiffness and serum testosterone concentration as well as other variables in men with type 2 diabetes mellitus. The relationships between bone stiffness and serum bioavailable testosterone concentrations as well as other variables including age, duration of diabetes, glycemic control (hemoglobin A(1c)), or body mass index were evaluated in 294 men with type 2 diabetes mellitus. An inverse correlation was found between stiffness index and age. A positive correlation was found between stiffness index and serum bioavailable testosterone concentration (r = 0.231, P = .0005). Stiffness index was significantly less in current smokers (81.6 +/- 17.7) than in past smokers (86.6 +/- 17.8, P = .0396) or nonsmokers (87.7 +/- 15.2, P = .0426). Multiple regression analysis demonstrated that serum bioavailable testosterone concentration (beta = .271, P = .0006) and smoking status (beta = -0.147, P = .0408) were independent determinants of stiffness index. In conclusion, bone stiffness was associated with serum bioavailable testosterone concentration but not associated with hemoglobin A(1c) or duration of diabetes in men with type 2 diabetes mellitus.

Bone mass and bone resorption in postmenopausal women with type 2 diabetes mellitus

The aim of the present study was to examine the relationships between bone mass or bone resorption evaluated by urinary cross-linked N-telopeptides of type I collagen (NTx) concentration and known and potential contributors to bone mass or bone resorption such as sex hormones, age, duration of diabetes, glycemic control (hemoglobin A(1c) [HbA(1c)]), body mass index (BMI), severity of diabetic complications, smoking status, and current treatment of diabetes in postmenopausal women with type 2 diabetes mellitus (n = 196). In addition, the relationship of bone mass to pulse wave velocity, which is an earlier indicator of cardiovascular disease, was investigated in a subgroup of patients (n = 120). Bone mass was evaluated by the quantitative ultrasound method. A higher stiffness index indicates higher bone mass. Inverse correlations were found between the stiffness index and age (r = -0.374, P < .0001) and between the stiffness index and log (urinary albumin excretion) (r = -0.170, P = .0398), and a positive correlation was found between the stiffness index and serum dehydroepiandrosterone sulfate (DHEA-S) concentration (r = 0.201, P = .0136). No significant correlations were found between the stiffness index and duration of diabetes, HbA(1c), BMI, or serum estradiol concentration. No significant correlations were found between urinary NTx concentration and age, duration of diabetes, HbA(1c), BMI, serum estradiol concentration, or serum DHEA-S concentration. The stiffness index correlated inversely with urinary NTx concentration (r = -0.262, P = .0002). No significant correlation was found between the stiffness index and pulse wave velocity (r = -0.165, P = .0714). Multiple regression analysis demonstrated that serum DHEA-S concentration was an independent determinant of the stiffness index (beta = .207, P = .0428). In conclusion, serum DHEA-S concentration correlated positively with bone mass, whereas glycemic control, BMI, or duration of diabetes did not correlate with bone mass or urinary NTx concentration in postmenopausal women with type 2 diabetes mellitus.

Assessment of low quantitative ultrasound values of calcaneus in Chinese mainland women

Calcaneus quantitative ultrasound (QUS) assessment is a safe and reliable method for evaluating skeletal status. Until now, considerable data have been accumulated on the distribution of QUS in Caucasian populations, whereas such data are still insufficient in Asian populations, especially in Chinese mainland. The present study aimed to obtain the distribution characteristic of calcaneus QUS in healthy Chinese women, and to further investigate the distribution of low bone mass by QUS stiffness index (SI). This study included 2,498 healthy Chinese females aged 10-87 yr. The QUS exhibited a characteristic mild rise and then fall pattern with increasing age. Age, body height, and weight were significant influencing factors on SI, especially age and weight. The prevalence of osteoporosis detected using instrument-derived T-score or internal T-score was different from that calculated according to calcaneus bone mass density (BMD) previously reported. Furthermore, between instrument-derived T-scores and internal T-scores, there were also significant differences. We concluded that the World Health Organization criteria from BMD may not be appropriate for QUS, and the instrument-derived T-score may also not be appropriate for the studied population. The results will be useful for predicting fracture risk of Chinese women and determining diagnostic criteria of osteoporosis by QUS.

Screening for low bone mass with quantitative ultrasonography in a community without dual-energy X-ray absorptiometry: population-based survey

BACKGROUND

Dual-energy x-ray absorptiometry (DXA) is the criterion standard to identify low bone mineral density (BMD), but access to axial DXA may be limited or cost prohibitive. We screened for low bone mass with quantitative ultrasonography (QUS) in a community without DXA, analyzed its reliability and obtained reference values and estimated the prevalence of low QUS values.

METHODS

We enrolled 6493 residents of Kinmen, Taiwan, and a reference group (96 men and 70 women aged 20-29 years) for this cross-sectional, community-based study. All participants completed a questionnaire and underwent ultrasonographic measurements. Reliability and validity of QUS measurements were evaluated. Broadband ultrasound attenuation (BUA) values were obtained and statistically analyzed by age, sex and weight. Annual loss of BUA was determined. Trends in the prevalence of QUS scores were evaluated.

RESULTS

Two QUS were used and had a correlation coefficient of 0.90 (p < 0.001). Calcaneal BUA was significantly correlated with BMD in the femoral neck (r = 0.67, p < 0.001) and BMD of the total lumbar spine (r = 0.59, p < 0.001). BUAs in the reference group were 92.72 +/- 13.36 and 87.90 +/- 10.68 dB/MHz for men and women, respectively. Estimated annual losses of calcaneal BUA were 0.83% per year for women, 0.27% per year for men, and 0.51% per year for the total population. The prevalence of severely low QUS values (T-score = -2.5) tended to increase with aging in both sexes (p < 0.001). Across age strata, moderately low QUS values (-2.5 < T-score < -1.0) were 31.6-41.0% in men and 23.7-38.1% in women; a significant trend with age was observed in men (p < 0.001).

CONCLUSION

Age-related decreases in calcaneal ultrasonometry, which reflected the prevalence of low bone mass, were more obvious in women than in men.

Characteristics of calcaneus quantitative ultrasound normative data in Chinese mainland men and women

INTRODUCTION

Quantitative ultrasound (QUS) assessment at the calcaneus, as a safe and reliable method for evaluating skeletal status, is rapidly gaining in popularity. Assessment by QUS provides three parameters of skeletal status: broadband ultrasound attenuation (BUA), speed of sound (SOS) and derived data-stiffness index (STI). The objective of the present study was firstly to determine the normative QUS data on healthy Chinese mainland men and women and secondly to investigate the effects of sex, age and body size on these three QUS parameters.

METHODS

A study cohort consisting of 725 healthy Chinese women and 568 men aged 10-83 years participated in this investigation. The three QUS parameters all exhibited a characteristic mild rise-then-fall pattern with increasing age in both sexes. Younger men and women had similar QUS values, while older women had lower values than older men. Age-related differences were more pronounced among females. Pearson's correlation and regression analysis showed that weight was a major determinant of QUS in both sexes, along with age.

RESULTS

There were some discrepancies between our data and results from other populations, even when the same type of QUS instrument was used, probably as a result of various factors, including ethnic, life-style environment and diet, among others.

CONCLUSIONS

These normative data will be useful for comparing the results of individual studies, predicting fracture risk of Chinese men and women and determining diagnostic criteria of osteoporosis by QUS.

Quantitative ultrasound calcaneus measurements: normative data for the Greek population

Quantitative ultrasound (QUS) is a peripheral bone densitometry technique that is rapidly gaining in popularity, and is widely used worldwide for the assessment of skeletal status. This, however, generally occurs in the absence of adequate clinical guidelines. As accurate interpretation of the results and correct classification in individual fracture risk assessment are of great value, the present study was carried out to establish a reference database for calcaneal QUS measurements across age group and gender in Greece. A total of 1205 subjects (821 females and 384 males) from three age groups (409 children, 341 adults and 455 elderly) were recruited. QUS measurements were performed at the heel with the Sahara device, which measures broadband ultrasound attenuation (BUA) and speed of sound (SOS), and then combines these variables into a single parameter, the quantitative ultrasound index (QUI). Overall, gender-related differences were more pronounced among the elderly, while age-related differences were more pronounced among females. Elderly men had higher QUS parameters than women of peer age, but no major gender differences were observed in children and adults. In males, only BUA showed a variation with age, being higher in adult and elderly men compared to boys. On the other hand, all QUS parameters varied significantly with age in females, the general trends being mildly positive from childhood to adulthood, when peak levels were observed, and negative thereafter. The results for the Greek population were in the range reported previously for other populations, but some discrepancies were evident, probably resulting from ethno-specific characteristics and different QUS instrumentation. Importantly, using the manufacturer's or the local database as the reference population for computing T-scores led to significantly different classification of subjects into conventional categories of risk. These data could be useful as a guide for comparing the results of individual studies, as well as for the assessment of Greek men and women at risk of fracture.

Effect of daily walking steps on ultrasound parameters of the calcaneus in elderly Japanese women

In this cross-sectional study, we investigated the effect of daily walking steps on ultrasound parameters of the calcaneus in elderly Japanese women. The subjects were 143 community-dwelling elderly women aged 61-87 years (mean age 71.4+/-5.5 years). The speed of sound (SOS), broadband ultrasound attenuation (BUA) and the stiffness index (Stiffness) of the calcaneus were measured. Walking steps were recorded using a pedometer for 7 consecutive days as an outcome measure of physical activity. In univariate analyses, steps/day significantly decreased with aging. SOS, BUA and Stiffness showed negative correlations with age and positive correlations with weight. Linear relationships were not seen between any of the ultrasound parameters and daily walking steps. Then, the ultrasound parameters were adjusted for age and/or weight using multiple regression models, and the relationships between the adjusted ultrasound measurements and walking steps were examined using quadratic regression models. Walking activity up to approximately 12,000 steps/day was positively associated with the adjusted ultrasound measurements, above which additional walking steps had no positive effect. We conclude that daily walking steps may be suitable for evaluating the relationship between ultrasound parameters and physical activity in elderly women, but further research is needed to confirm the effect of daily walking steps on the rate of bone loss.

Comparison of imaging-guided and non-imaging-guided quantitative sonography of the calcaneus with dual X-ray absorptiometry of the spine and femur

OBJECTIVE

The purpose of our study was to evaluate the diagnostic agreement between imaging-guided and non-imaging-guided quantitative sonography of the calcaneus and dual X-ray absorptiometry of the spine and femur to show osteoporosis.

SUBJECTS AND METHODS

In 113 patients (73 women, 59 +/- 14 years old; 40 men, 48 +/- 16 years old), dual X-ray absorptiometry of the lumbar spine and the proximal femur, imaging-guided quantitative sonography, and non-imaging-guided quantitative sonography of the calcaneus were performed. The percentage of patients having a T-score equal to or less than a threshold of -2.5 SDs (prevalence of osteoporosis) was calculated for each imaging technique. The diagnostic agreement of the three techniques in identifying individuals with osteoporosis was assessed.

RESULTS

Eleven percent of the women and 8% of the men were classified as osteoporotic by imaging-guided quantitative sonography, and 38% of the women and 25% of the men were so classified by non-imaging-guided quantitative sonography. At dual X-ray absorptiometry of the spine, 44% of the women and 38% of the men were classified as osteoporotic, and, at different femoral regions, 19-60% of the women and 8-38% of the men were so classified. Kappa analysis for both quantitative sonography techniques was not significant. Kappa analysis for both quantitative sonography techniques and dual X-ray absorptiometry showed diagnostic agreement to be generally poor.

CONCLUSION

No advantage in diagnostic accuracy could be found for imaging-guided quantitative sonography. The considerable diagnostic disagreement between both quantitative sonography techniques and dual X-ray absorptiometry could be confusing in daily clinical practice.

Community-based survey of low quantitative ultrasound values of calcaneus in Taiwan

This study investigated prevalence and associated-factors of low quantitative ultrasound (QUS) values by screening calcaneal QUS parameters--broadband ultrasound attenuation (BUA) and speed of sound (SOS)--in population samples of three different Taiwanese communities. The study included 6,322 subjects (2,631 male and 3,691 female), aged 31 yr old or more in Shih-Pai (a metropolitan area in northern Taiwan),Yu-Chi (a mountain area in central Taiwan), and A-Lein (a seaside area in southern Taiwan). The overall response rate was 50.2%. The correlation between BUA and SOS was 0.684, p<0.001. From those who responded, we selected 403 subjects aged 31-40 yr as the reference (the young group), and their BUA was 65.34+/-7.91 dB/MHz. The t-score was calculated from the BUA data of our reference group. The percentile of -2.5<t-score<-1.0 and t-score< or =-2.5 in male subjects was 21.4 and 2.9%, respectively, and in female subjects 24.2 and 14.1%, respectively. The BUA of urban area subjects was higher than that of rural area subjects in almost all age-strata, and overweight was noted to be a protective factor. The effect of age-adjusted odds ratio (AOR) on low QUS values in females was significantly increased every 10 yr from 1.55, 5.13, 13.81, 34.29, to 38.14. This survey showed that age-related decreases in calcaneal ultrasonometry, indicating prevalence of low QUS values, were more obvious in female than male subjects. Overall 38.3% of the female Taiwanese had low QUS values, and this is approximately equivalent to the lifetime risk of fracture at the hip, spine, or distal forearm in Caucasian women. The specific t-score designation, as World Health Organization (WHO) criteria, applied to calcaneal QUS are reasonable when the reference group is selected from the same population.

Diagnostic agreement of two calcaneal ultrasound devices: the Sahara bone sonometer and the Achilles+

Quantitative ultrasound for the assessment of skeletal status is an evolving method in the diagnosis of osteoporosis. In this cross-sectional study we investigated the diagnostic agreement between the Sahara bone sonometer and the Achilles+ with respect to broadband ultrasound attenuation (BUA), speed of sound (SOS) and stiffness/quantitative ultrasound index (QUI). 309 healthy females without diseases or medications known to influence bone metabolism (with the exception of oestrogen) were recruited at two participating centers (Erlangen and Berlin). 33% of subjects were taking oestrogens. There was no significant difference in BUA, SOS, and stiffness/QUI between oestrogen and non-oestrogen takers. In vivo precision (expressed as root mean square coefficient of variation) was calculated from two repeat measurements and analyzed in both centres. Mean values were 1.57% (BUA Achilles+), 3.64% (BUA Sahara), 0.35% (SOS Achilles+), 0.39% (SOS Sahara), 2.22% (stiffness Achilles+) and 3.04% (QUI Sahara). Between the two devices we observed a strong correlation for SOS (r=0.89, p<0.01) and stiffness/QUI (r=0.83, p<0.01), and a moderate correlation for BUA (r=0.68, p<0.01). All parameters were moderately negatively associated with age (r=-0.38 to -0.48; p<0.01 for all correlations). Kappa (kappa) scores used to report diagnostic agreement were calculated for tertiles and "equivalent T-scores". The tertiles divide the cohort on both scanners into the same number of subjects above and below a given T-score. Diagnostic agreement using tertiles was poor to moderate (kappa< or =0.51). Diagnostic agreement using equivalent T-score agreement, again, was poor to moderate for BUA but fair to good for SOS and stiffness/QUI (0.59< or =kappa< or =0.73). We conclude that diagnostic agreement between the two devices is at best comparable to the agreement of a dual X-ray absorptiometry measurement using the same densitometer at two different skeletal sites. It is therefore insufficient to compare directly two measurements of an individual patient on both ultrasound devices. Standardization of quantitative ultrasound is very much needed.

Quantitative US of the calcaneus: cutoff levels for the distinction of healthy and osteoporotic individuals

PURPOSE

To calculate cutoff levels for quantitative ultrasonography (US) performed to distinguish healthy individuals and those with osteoporosis identified with dual x-ray absorptiometry.

MATERIALS AND METHODS

In 1,357 patients (856 females, aged 55.1 years +/- 15.4 [mean +/- SD]; 501 males, aged 50.4 years +/- 15), bone mineral density measurements of the lumbar spine (posteroanterior, L1 through L4) and femoral neck were obtained, and quantitative US was performed to determine the stiffness of the calcaneus. Individuals with a T score less than -2.5 (osteoporotic) at the spine and femur were identified, and upper T-score cutoff values (3 SDs from the mean) in the groups of male and female patients with osteoporosis were identified.

RESULTS

Females with dual x-ray absorptiometric values that were indicative of osteoporosis of the spine had an upper T-score cutoff value of -1.0 (males, -0.2). Females who had femoral osteoporosis showed an upper quantitative US T-score cutoff value of -0.6 (males, 0).

CONCLUSION

Cutoff values may permit the use of quantitative US to screen for the presence of osteoporosis in the spine and femur. Quantitative US will help to prevent unnecessary dual x-ray absorptiometric and conventional radiographic examinations.

Diagnostic disagreement of imaging quantitative sonography of the calcaneus with dual X-ray absorptiometry of the spine and femur

OBJECTIVE

This study evaluates the diagnostic agreement between imaging quantitative sonography of the calcaneus and dual X-ray absorptiometry of the spine and femur for diagnosing osteoporosis.

MATERIALS AND METHODS

In 498 female patients (56 +/- 18 years old), bone mineral density measurements by dual X-ray absorptiometry of the lumbar spine (posteroanterior, L1--L4) and the proximal femur and imaging quantitative sonography of the calcaneus were performed. The percentage of patients having T-scores less than or equal to a threshold of -2.5 standard deviations below a young normal reference was used to compare quantitative sonography with dual X-ray absorptiometry. The diagnostic agreement was assessed using kappa scores.

RESULTS

Approximately 30% of the patients had a T-score less than or equal to -2.5 standard deviations as assessed by imaging quantitative sonography (broadband ultrasound attenuation), 26.5% as assessed by dual X-ray absorptiometry of the spine, and 16.7--56.4% as assessed by dual X-ray absorptiometry of the different regions of interest at the femur. Kappa analysis showed that severe diagnostic disagreement exists among broadband ultrasound attenuation and dual X-ray absorptiometry (kappa = 0.28-0.42).

CONCLUSION

Considerable diagnostic disagreement exists between imaging quantitative sonography and dual X-ray absorptiometry of the spine and femur. The disagreement is in the same range as that reported recently in comparisons of dual X-ray absorptiometry and nonimaging quantitative sonography. In general, no distinct advantage for imaging quantitative sonography could be found when compared with other techniques.

Evaluation of bone strength: correlation between measurements of bone mineral density and drilling force

Bone drilling is a major part of modern orthopaedic surgery which involves the internal fixation of fractured bones. The investigation of bone drilling described in this paper demonstrates the contribution of automation technology towards the study of bone strength. The aim of this preliminary investigation is to establish a relationship between bone drilling forces and measurements of bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA). A linear relationship with a high coefficient of correlation has been found between average drilling forces and BMD measurements at both the greater trochanter and the femoral head of porcine femurs when drilling in the anterior-posterior (AP) direction (i.e. the direction of the DXA scan). It has also been found that in the normal drilling direction (i.e. in the cervical axis direction), which is orthogonal to the DXA scanning direction, there are similar trends between the drilling forces and BMD levels in regions where bone density is more consistent (e.g. the femoral head). The findings of this investigation indicate that analysis of bone drilling forces has the potential to provide useful information about the strength of bone.

Quantitative ultrasound and dual X-ray absorptiometry measurements of the calcaneus in patients on maintenance hemodialysis

It has been suggested that quantitative ultrasound measurements (QUS), which reflect mainly bone density, could be influenced by bone micro-architecture. The aim of the study was to assess whether the relationship of QUS to dual X-ray absorptiometry (DXA) would reflect abnormalities of bone structure observed in renal osteodystrophy. QUS and bone mineral density of the calcaneus (BMDc) were measured by DXA in 30 patients on maintenance hemodialysis and 34 age- and gender-matched controls. QUS parameters and BMDc were significantly lower in hemodialysis patients than in controls (speed of sound [SOS] and broadband ultrasound attenuation [BUA], p = 0. 030; stiffness, p = 0.003; BMDc, p = 0.006). Bone measurements were not correlated with serum parathyroid hormone (PTH). The regression lines of SOS, BUA, and stiffness to BMDc were not significantly different from that of the controls. When dividing the patients into two subgroups according to their median PTH (203 pg/mL), the slopes of the regression lines of BUA to BMDc were significantly different between these two subgroups (p = 0.052). The slope of the subgroup with PTH </= 203 pg/mL was significantly different from that of the controls (p = 0.030). In conclusion, QUS of the calcaneus can be used for bone assessment in patients on maintenance hemodialysis. The differences in the slopes of patients with a less pronounced degree of hyperparathyroidism compared with patients with a higher degree of hyperparathyroidism and to controls suggest that BUA of the calcaneus contains information on bone complementary to DXA measured at the same site. The clinical relevance of this finding is presently unclear.

Quantitative ultrasound in postmenopausal osteoporosis

Ultrasound has been proposed as a low-cost, radiation-free method for osteoporosis assessment in postmenopausal women. Large prospective studies have shown that ultrasound parameters can be used for fracture risk estimate in this population, providing that adequate quality control is performed. The places of both ultrasound and the current gold standard method for bone assessment, dual energy x-ray absorptiometry, are still to be determined. Further studies are needed on the diagnosis of osteoporosis using ultrasound, because current diagnostic thresholds, designed by the World Health Organization, do not apply to this-new technology. Monitoring of skeletal changes and treatment effects by ultrasound cannot be recommended.

Quantitative ultrasound of the calcaneus with parametric imaging: correlation with bone mineral density at different sites and with anthropometric data in menopausal women

OBJECTIVE

To prospectively study the relationship of quantitative ultrasound of the calcaneus with anthromopometric variables and with bone mineral density (BMD) assessed at the level of the calcaneus as well as at other sites.

METHOD

Osteosonography of the non-dominant calcaneus was performed in 135 menopausal women, using a DTU-one device with parametric imaging. Broadband ultrasound attenuation (BUA) and speed of sound (SOS) were assessed. BMD of the calcaneus (BMDcal) was measured using dual energy X-ray absorptiometry (DXA), in a subregion matched with the region of interest for osteosonography. BMD of the lumbar trabecular bone was measured using quantitative computed tomography (BMD QCT) while the non-dominant hip was studied using DXA, which provided the total bone mineral density (BMDhip) and that of the Ward triangle (BMDWard).

RESULTS

The Pearson correlation coefficients between BUA, SOS and the various measurements of BMD ranged from 0.305 (SOS versus BMDhip) to 0.717 (BUA versus BMDcal). BMD QCT and BMDWard were found to depend on age, but not on weight or height, while BUA, SOS, BMDcal, BMDhip were unrelated to age, but correlated with weight (SOS, BMDhip) or with weight and height (BUA, BMDcal). In a multiple stepwise regression analysis, age was a significant predictor for BMD QCT, BMD hip and BMDWard; BMD QCT, BMDWard and BMDhip admitted BUA as sole predictor, while BMDcal was significantly related to both BUA and SOS.

CONCLUSION

BUA and SOS of the calcaneus, assessed in 135 menopausal women using a parametric imaging device, reflected BMDcal, measured with DXA at a matched region of interest, and did not decline significantly with age.

Prediction of bone strength of distal forearm using radius bone mineral density and phalangeal speed of sound

This investigation compares quantitative ultrasound (QUS) measurement of the phalanges with peripheral quantitative computed tomography (pQCT) and dual X-ray absorptiometry (DXA) measurement of the forearm, to estimate the strength of the distal radius in 13 cadaveric forearms. The cadavers were scanned at the distal radius by pQCT and DXA for bone mineral density (BMD) and at the approximate phalanges by QUS for speed of sound (SOS). The distal radii were subjected to a simulated Colles fracture produced with a materials testing machine. The load at which the distal radius was fractured was considered as a representation of bone strength. The bone strength correlated significantly with SOS at different phalanges (r = 0.63-0.72), BMD at different regions of interest by DXA (r = 0.67-0.75), and cortical BMD at different sites by pQCT (r = 0.61-0.67). Standard stepwise regression analysis showed that adding phalangeal SOS into forearm densitometric variables significantly enhanced the statistical power for prediction of the strength of the distal radius. Our results suggest that, for assessment of site-specific distal forearm strength, QUS measurement of the phalanges is comparable to forearm densitometry. Phalangeal QUS may add clinical value if distal forearm strength has a high priority.

Calcaneal ultrasound measurements are determined by age and physical activity. Studies in two Swedish random population samples

AIM

To present reference values and correlations with body composition, blood variables and lifestyle factors.

SUBJECTS

Two random population samples from Göteborg, Sweden, one comprising 184 men and 455 women aged 25-64 years (MONICA) and the other 860 women aged 55-82 years (BEDA) were studied.

METHODS

Calcaneal ultrasound measurement (LUNAR Achilles) and bioimpedance were measured. Smoking habits, coffee consumption, physical activity, psychological stress, education and marital status, as well as blood lipids, blood pressure, and fractures were studied.

RESULTS

Broadband ultrasound attenuation and stiffness were higher in men than in women (P < 0. 001), but speed of sound did not differ between sexes. Speed of sound, broadband ultrasound attenuation and stiffness decreased with age (P < 0.001). In both sexes speed of sound, broadband ultrasound attenuation and stiffness correlated positively to body size variables, and negatively with smoking in women after adjustment for age. Speed of sound, broadband ultrasound attenuation and stiffness were positively related to physical activity in both sexes, and these relationships were the only ones that remained in multivariate analyses in addition to age (negative). Osteoporotic fractures increased with age. Speed of sound, broadband ultrasound attenuation and stiffness were lower amongst women with osteoporotic fractures.

CONCLUSION

Speed of sound, broadband ultrasound attenuation and stiffness decreased with age and increased with physical activity, but body weight and height were not correlated in multivariate analyses. Osteoporotic fractures increased with age and were associated with lower calcaneal ultrasound values.

Comparison of calcaneal ultrasound and DXA in young women

PURPOSE

The purpose of the study was to assess quantitative ultrasound (QUS) parameters in collegiate female gymnasts, a population whose training incorporates high-impact loading, which is particularly osteogenic, and to determine the discriminative capacity of this relatively new radiation-free technique compared with bone densitometry in a young healthy population.

METHODS

We studied 19 collegiate gymnasts and 23 healthy controls undergoing regular weight-bearing activity, matched for age (gymnasts 19.2 +/- 1.2, controls 19.9 +/- 1.6 yr) and body weight (gymnasts 56.7 +/- 3.7, controls 57.7 +/- 7.8 kg). QUS parameters of the calcaneus (broadband ultrasound attenuation (BUA), bone velocity (BV), and speed of sound (SOS)) were measured by a Walker Sonix UBA 575+. Bone mineral density (BMD; g x cm(-2)) of the lumbar spine, hip (femoral neck, trochanter, Ward's triangle) and whole body was assessed by dual energy x-ray absorptiometry (DXA, Hologic QDR 1000/W). Data analysis included unpaired two-tailed Student's t-tests, analysis of variance, Pearson product-moment, and Spearman rank-order correlations.

RESULTS

Regional and whole body BMD of gymnasts was greater than controls (P < 0.001), with the difference being 7-28%. Average QUS parameters of the right and left calcaneus were also higher (P < 0.001) in the gymnasts. BUA, BV, and SOS were significantly (P < 0.001) correlated to each bone site with r = 0.54-0.79. Analysis of receiver operating characteristic (ROC) curves indicated no significant difference in sensitivity and specificity for QUS and DXA measures.

CONCLUSIONS

These results indicate that QUS parameters of the calcaneus are higher in young women gymnasts compared to individuals who undergo regular weight-bearing activity and that QUS parameters are able to discriminate between these two groups in a similar manner as does regional and whole body BMD.

Hip fracture discrimination by imaging ultrasound measurements of the calcaneus

Quantitative ultrasound measurements of the os calcis have recently been upgraded with imaging facilities. This has made measurements of a specific region of interest possible and improved the reproducibility of the method, but the diagnostic ability of imaging ultrasound has not yet been investigated thoroughly. We measured broadband ultrasound attenuation (BUA) and speed of sound (SOS) using imaging ultrasound as well as forearm bone mineral density (BMDarm) using dual-energy X-ray absorptiometry in three age-matched groups of women: (1) 25 women who were admitted to hospital due to a hip fracture; (2) 23 women who were admitted to hospital due to a fall without any fracture; and (3) 26 normal women. Furthermore, BMD of the hip (BMDhip) was measured in a subgroup of the hip fracture patients and those who had fallen. All measurements were performed during the index hospitalization in order to avoid any influence from bone loss due to immobilization after the fracture. We found a -0.48 SD deviation from expected age-matched values in BUA among the hip fracture patients, whereas the patients who had fallen showed a +0.16 SD deviance. For SOS, the figures were -0.70 SD for the hip fracture group and -0.06 SD for the patients who had fallen. For BMD of the arm we found values of -0.65 SD and +0.08 SD, respectively, whereas the figures for BMD of the hip were -0.66 SD and +0.13 SD, respectively. All parameters were significantly lower in the hip fracture group compared with the patients who had fallen. None of the parameters in the patients who had fallen deviated significantly from expected normal age-matched values. Neither BMD of the arm or BMD of the hip separated hip fracture patients and patients who had fallen significantly better than ultrasound (BUA or SOS) did. We conclude that imaging ultrasound (BUA or SOS) separates age-matched groups of hip fracture and non-fracture patients as well as BMD measurements do.

Ultrasonic measurement of the calcaneus in Polish normal and osteoporotic women and men

In this cross-sectional study, 964 subjects (740 postmenopausal women and 224 men) who underwent ultrasound measurement of the calcaneus at the outpatient osteoporotic clinic in the years 1993-1996 were evaluated. The aim of the study was to compare the influence of age, years since menopause (YSM), and body size on ultrasound variables in normal and osteoporotic male and female populations as well as to assess the ability of quantitative ultrasound (qUS) to discriminate between healthy and osteoporotic individuals. The subjects were divided into four age-matched groups: normal women (n = 601, mean age 56.3 +/- 4.8 years); osteoporotic women (n = 139, mean age 56.5 +/- 4.8 years); normal men (n = 148, mean age 56.2 +/- 10.2 years); and osteoporotic men (n = 76, mean age 56.5 +/- 10.7 years). Persons with a history of a disease and/or medications known to affect bone metabolism were excluded. Broadband ultrasound attenuation (BUA, in decibels per megahertz) and speed of sound (SOS, in meters per second) were measured using Achilles device (Lunar, Madison, WI). Short- and long-term in vitro coefficients of variation (CVs) were: 1.23% and 0.54% for BUA and 0.12% and 0.14% for SOS, respectively. Short-term in vivo CVs were: in women, BUA 1.8% and SOS 0.22%; and, in men, 2.48% and 0.33%, respectively. SOS and BUA values were significantly higher in healthy men (1517.5 +/- 35.3 m/sec, 114.0 +/- 13.3 dB/MHz) than in healthy women (1511.1 +/- 25.6 m/sec, 108.7 +/- 9.5 dB/MHz) (p < 0.000001). The two ultrasound variables had higher values in osteoporotic men (SOS = 1492.6 +/- 24.6 m/sec, BUA = 106.1 +/- 11.6 dB/MHz) in comparison to osteoporotic women (SOS = 1490.4 +/- 19.5 m/sec, BUA = 103.2 +/- 8.6 dB/MHz), but the differences did not achieve significance. In both genders, ultrasound parameters were significantly lower in osteoporotic groups (p < 0.000001). The following age-adjusted odds ratios were obtained: in women, 1.7 (95% CI 1.42-2.03) for BUA, and 2.3 (95% CI 1.87-2.81) for SOS; in men, 1.05 (95% CI 0.03-2.07) for BUA, and 2.13 (95% CI 0.77-3.49) for SOS. ROC analyses performed in both genders showed the following area under the curve data: in women, 0.66 for BUA, and 0.74 for SOS; and, in men, 0.66 for BUA, and 0.71 for SOS. Multiple regression analysis showed age to be the main negative determinant of both ultrasound variables in healthy women, and YSM in osteoporotic women. In both genders, weight was found to have a positive influence on SOS and BUA values, whereas the effect of height was weaker and generally negative. It can be concluded that ultrasound measurement at the calcaneus is able to discriminate between normal male/female and osteoporotic male/female populations in a similar manner. Women had greater rates of decrease in BUA and SOS with age compared with rates in men, and the decrease was greater in normal individuals in both genders. Distinct gender-related differences were noted in regard to correlations of ultrasound parameters with body size.

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.

A comparison of radial peripheral quantitative computed tomography, calcaneal ultrasound, and axial dual energy X-ray absorptiometry measurements in women aged 45-55 yr

Perimenopausal bone loss is considered to affect trabecular bone preferentially. Peripheral quantitative computed tomography (pQCT) quantifies trabecular bone mineral density (BMD) independently at the ultradistal radius. This article examines differences in pQCT BMD between late premenopausal and early postmenopausal women, comparing the differences with calcaneal ultrasound and axial dual energy X-ray absorptiometry measurements. One hundred nineteen normal perimenopausal women aged 45-55 yr who attended a randomized osteoporosis screening program were stratified by menopausal status into premenopausal (PRE: n = 79) and postmenopausal (POST: n = 40) groups. All measurements were lower in the postmenopausal group with the exception of ultrasonic velocity (PRE vs POST: 1397 +/- 53.8 vs 1421 +/- 58.5 m/s, p = 0.037). Total (391.8 +/- 52.9 vs 366.3 +/- 68.6 g/cm(3), p = 0.013) and subcortical (533.6 +/- 59.4 vs 504.3 +/- 79.8 g/cm(3) p = 0.018), but not trabecular (187.5 +/- 38.8 vs 173.2 +/- 46.6 g/cm(3), p = 0. 098) or cortical (561 +/- 53.4 vs 551.2 +/- 66 g/cm(3), p = 0.174), pQCT BMD measurements were significantly lower in the POST group, as were ultrasonic attenuation (79.4 +/- 16 vs 72.3 +/- 18.0 dB/Mz, p = 0.034), DXA spine (1.032 +/-16 vs 0.959 +/- 0.2 g/cm(2), p = 0.003), and all hip (p </= 0.001) measurements. Although body mass index (BMI) was positively and menopausal status and age negatively correlated with most bone mass measurements, adjusting for BMI did not alter the relative deficits in postmenopausal compared with premenopausal women. This study suggests that early postmenopausal bone loss at the radius preferentially affects subcortical, rather than trabecular, bone in the appendicular skeleton, which suggests preferential trabecular bone loss in the axial skeleton.

Reproducibility of phalanx osteosonography and relation with forearm peripheral quantitative computed tomography: single finger versus average measurement on the last four fingers

The aim of this study was to evaluate the in vivo short-term reproducibility of amplitude-dependent speed of sound (AD-SOS) measured at the proximal phalanx, using an Igea DBM Sonic 1200 device, as well as its relationship with bone mineral density of the ultradistal radius, assessed using peripheral quantitative computed tomography (pQCT). In particular, the authors wished to evaluate whether average measurements on the last four fingers, as recommended by the manufacturer, yielded or not more information than measurements on one single finger. For the precision study, the authors carried out phalanx osteosonography ten times once every other day in ten healthy young women. To compare with pQCT of the radius, 37 women referred for screening of osteoporosis (mean age 60 years) were studied. AD-SOS was reported for each finger separately, as well as an average; pQCT (XCT 960 Stratec) yielded trabecular (BMDt); cortical (BMDc); and total (BMDtot) bone mineral densities, as well as the cortical area (Ac). The reproducibility of AD-SOS was significantly higher for the middle finger (mean coefficient of variation (CV) 1.1%) and the index than for the ring and small (mean CV 2.7%) finger. The middle finger consistently showed the best correlations with pQCT variables; the relationships involving BMDc (r = 0.54), BMDtot (r = 0.62) and Ac (r = 0.61) were stronger than that with BMDt (r = 0.34). The authors conclude that phalanx AD-SOS is moderately correlated with BMD of the ultradistal radius--at least when it includes the cortical component--and that reporting AD-SOS for the middle finger--instead of an average value--improves the reproducibility and possibly the relevance of phalanx osteosonography.

Bone densitometry: applications in sports-medicine

Physical exercise and sports increase muscular mass and the remodelling process of bones. The increment of bone depends on the type and the quality of sport. Short-term high-performance activities such as sprint, tennis, fencing lead to increased bone mineral density as well as weight lifting or heavy athletics. Swimming, bicycling, walking are associated with good musculature conditioning without an increase of bone mass. The effects on the bone by performing endurance activities are controversially discussed. Excessive sport leads to an increase of fatigue fractures. Low bone mass may result from hormonal disregulation in female athletes.

Methodology for the clinical assessment of medical instrumentation: evaluating ultrasonometers

Medical instruments can be used for screening, diagnosis, prognosis, and monitoring natural history or therapeutic intervention. With the developing role of ultrasonometry it is important to assess how these instruments will effectively be used for each of these utilizations. No two types of ultrasonometers are the same: there are differences in anatomical sites, measurement variables and methodology in obtaining those variables. To determine optimal utilization the clinician has to evaluate each instrument. Eight factors have to be considered for each utilization comprising of discrimination, precision, reliability, relevance, acceptance by regulatory authorities, inexpensive, acceptability to the patient, and safety. This paper discusses these factors and presents an overview in relationship to the utilization of instruments using ultrasonometry.

The role of quantitative ultrasound in the assessment of bone: a review

Quantitative ultrasound (QUS) bone measurement is a promising, relatively new technique for the diagnosis of osteoporosis. Unlike to the more established method of bone densitometry [measurement of bone mineral density (BMD) e.g. using dual X-ray absorptiometry (DEXA)], QUS does not use ionizing radiation. It is cheaper, takes up less space and is easier to use than densitometry techniques. The two QUS parameters currently measured are broadband ultrasound attenuation (BUA) and speed of sound (SOS). The reported age-related changes for healthy women range from -0.27% to -1.62% per year for BUA and from -0.06% to -0.19% per year for SOS. Precision ranges from 1.0 to 3.8% (CV) for BUA and from 0.19 to 0.30% (CV) for SOS. The new method of imaging ultrasound has improved the precision of QUS measurements. QUS is significantly correlated with BMD. Studies with the latest equipment have shown r-values between 0.6 and 0.9 in site-specific measurements, and QUS is thus believed to reflect mainly BMD. However, other studies indicate that QUS measures something other than the actual mineral content of bone, namely bone quality, e.g. in vitro studies have shown that QUS reflects trabecular orientation independently of BMD. In both cross-sectional and prospective studies, QUS seems to be as good a predictor of osteoporotic fractures as BMD. In two large prospective studies, QUS also predicted fracture risk independently of BMD. QUS has just begun to be used systematically for monitoring the response to anti-osteoporotic treatments in prospective trials. In the studies performed, QUS has been found to be useful in the follow-up of patients. QUS is thus a promising new technique for bone assessment.

Age- and menopause-related changes in speed of sound and ultrasound attenuation of the os calcis in a healthy Italian female population

This study assessed changes in ultrasonometric variables of bone (speed of sound, broadband ultrasound attenuation and stiffness) related to age and years since menopause in a normal Italian female population. Two hundred and thirty-one healthy female subjects, age range 18-78 years, divided into two groups (113 pre-menopausal, age range 18-51 years, and 118 post-menopausal, age range 46-78 years), were investigated. The results obtained show that there was a linear decrease in speed of sound, broadband ultrasound attenuation and stiffness with age; a similar pattern was also observed in post-menopausal women as far as the correlations between ultrasonometric variables and both age and years since menopause were concerned. In particular, speed of sound declined at a rate of 0.86 m/s for each year post-menopause, while broadband ultrasound attenuation declined at 0.4 dB/MHz, and stiffness at 0.5 units. These findings suggest that ultrasound variables might be able to detect characteristics of bone that are barely influenced by estrogen deficiency, and depend on other factors. Therefore, ultrasound measurement should be considered as a possible alternative to x-ray densitometry for the assessment of the skeleton.

Utility of ultrasound to assess risk of fracture

Traditional assessments of bone properties have utilized densitometry techniques such as Dual Energy X-ray Absorptiometry (DXA). Recently, quantitative ultrasound (QUS) has been introduced as an alternative method of assessing bone properties. Advantages of QUS over X-ray techniques include low costs, portability, and nonionizing radiation. Proponents of QUS have claimed that this technology can provide information not only about the density but also about the structure and mechanical properties of bone. There are two major questions that need to be answered for those who seek to diagnose bone disorders with ultrasound: (1) what does quantitative ultrasound actually measure, and, even more importantly, (2) what is its clinical utility? In this review we will briefly examine the first question and will focus on the utility of ultrasound in clinical trials to discriminate between fractures and non-fractures and to predict the risk of fractures.

Precision and discriminatory ability of calcaneal bone assessment technologies

To determine if measuring skeletal status at the calcaneus is a potentially valuable technique for diagnosing osteoporosis, we examined five calcaneal assessment techniques in 53 young normal women and 108 postmenopausal women with osteoporosis and compared these measurements to dual-energy X-ray absorptiometry (DEXA) at the calcaneus, hip, and spine. The five instruments, including single-energy X-ray absorptiometry (SEXA) and four quantitative ultrasound (QUS) instruments, were evaluated for precision, ability to discriminate osteoporotic from young normal subjects, and correlation to the other instruments. The coefficient of variation (%CV) for instrument, positioning, interobserver, and short-term precision of the five calcaneal instruments ranged from 1.34-7.76%, 1.63-7.00%, 1.84-9.44%, and 1.99-7.04%, respectively. The %CVs for positioning, interobserver, and short-term precision were similar for calcaneal DEXA, calcaneal SEXA, and stiffness (as measured by Achilles). The %CVs for instruments precision were similar between calcaneal DEXA and SEXA. The ability of the five calcaneal instruments to discriminate osteoporotic from young normal subjects was similar based on the analysis of area under the receiver operating characteristic curves (range 0.88-0.93) and equivalent to DEXA of the calcaneus and hip (0.88-0.93). The correlations between the measurements of five calcaneal instruments were strong (0.80 < or = r < or = 0.91, p < 0.001). These data suggest that although the precision is variable, the calcaneal QUS and SEXA instruments can discriminate between osteoporotic patients and young normal controls and appear to be a useful technique for assessment of osteoporosis.

Quantitative ultrasound techniques for the assessment of osteoporosis: expert agreement on current status. The International Quantitative Ultrasound Consensus Group

Quantitative ultrasound (QUS) methods have been introduced in recent years for the assessment of skeletal status in osteoporosis. The performance of QUS techniques has been evaluated in a large number of studies. Reviewing existing knowledge, an international expert panel formulated the following consensus regarding the current status of this technology. To date, evidence supports the use of QUS techniques for the assessment of fracture risk in elderly women. This has been best established for water-based calcaneal QUS systems. Future studies should include the predictive validity of other QUS systems. Additional clinical applications of QUS, specifically the assessment of rates of change for monitoring disease progression or response to treatment, require further investigation. Its low cost and portability make QUS an attractive technology for assessing risk of fractures in larger populations than may be suitable or feasible for bone densitometry. Additional investigations that assess innovative QUS techniques in well defined research settings are important to determine and utilize the full potential of this technology for the benefit of early detection and monitoring of osteoporosis.