Calcaneal Ultrasound Imaging in Healthy Children and Adolescents: Relation of the Ultrasound Parameters BUA and SOS to Age, Body Weight, Height, Foot Dimensions and Pubertal Stage

We investigated the quantitative ultrasound (QUS) parameters broadband ultrasound attenuation (BUA) and speed of sound (SOS) measured in the posterior part of the calcaneus at the region of interest (ROI) with the lowest attenuation, using an ultrasound imaging device (UBIS 3000) in 491 healthy Caucasian children and adolescents (262 girls, 229 boys) between 6 and 21 years old. The relation of age, body weight, height, foot dimensions and pubertal stage to BUA and SOS was assessed. BUA increased nonlinearly with age in boys and girls, r ² being 0.44 (p<0.001) and 0.57 (p<0.001), respectively. SOS increased linearly with age in girls (r ²= 0.04, p<0.001). There was no significant increase in SOS in boys (r ²= 0.01, p>0.05). Heel width was significantly correlated with BUA (r= 0.20, p<0.005 in boys; r= 0.27, p<0.05 in girls) and with SOS (r=−0.19, p<0.005 in boys; r=−0.08, p<0.05 in girls). After downward adjustment of the ROI size according to foot length quartiles, significantly lower BUA and SOS values were found compared with those with the standard ROI size of 14 mm. After correction for heel width and adjustment of the ROI size based on foot length, BUA and SOS were significantly associated with age in boys (r ²= 0.36, p<0.001 and 0.06, p<0.05) and in girls (r ²= 0.53 and 0.06, both p<0.001). Tanner stage was significantly correlated with BUA (r= 0.62, p<0.001 in boys; r= 0.73, p<0.001 in girls) but not with SOS. BUA but not SOS increased significantly with the number of years since menarche (p<0.001). In a multiple stepwise regression analysis in boys, age, weight and foot length were independent predictors for BUA, and age and foot length for SOS. In girls, age and weight were independent predictors for BUA and age was the only independent predictor for SOS. After correction for age, pubertal stages and heel width were no longer determinants for QUS parameters in either boys or girls. In conclusion, BUA increased significantly with age in both sexes. SOS increased with age in both boys and girls, but the increase was small and not statistically significant in boys. SOS, as measured with the UBIS 3000 device, may therefore not be appropriate to assess skeletal status in healthy children. Whether SOS and BUA are affected in children with skeletal disorders has yet to be determined. In boys, age, weight and foot length were independent predictors for BUA and age and foot length for SOS. In girls, age and weight were independent predictors for BUA and age was the only independent predictor for SOS. In our opinion, children with small feet should be measured with a smaller ROI diameter than those with larger feet. Received: 28 October 1999 / Accepted: 19 June 2000     

Ultrasound bone densitometry of Os calcis in elderly Japanese women with hip fracture

We evaluated 138 elderly patients (mean age 79 years) within 2 weeks after hip fracture (67 cervical and 71 trochanteric) using an Achilles ultrasound bone densitometer (Lunar Corporation, Madison, WI). The ultrasound variables of speed of sound (SOS in m/second), broadband ultrasound attenuation (BUA in dB/MHz), and stiffness (%) index were measured on the os calcis. Ultrasound densitometry also was done on 563 normal postmenopausal women to assess normal age changes. An elderly subgroup (n = 138) served as age-matched controls for the hip fracture group. Further subgroups of 33 patients and 33 controls were compared for lumbar spine and femoral neck BMD. There were no statistically significant differences between the hip fracture group and age-matched controls in height and weight, but each ultrasound variable was significantly lower for the hip fracture group (P < 0.0001). For the hip fracture group, SOS was 1470 ± 19 m/second, BUA was 84.3 ± 8.4 dB/MHz, and the stiffness index was 47.8 ± 9.2%, whereas for the age-matched controls, SOS was 1486 ± 27 m/second, BUA was 94.0 ± 11.4 dB/MHz, and the stiffness index was 59.1 ± 12.5%. There were no significant differences between cervical and trochanteric hip fracture groups. Logistic regression analysis showed that a change of the ultrasound values by 1 standard deviation (SD) changed the odds ratio for SOS, BUA, and stiffness index by 2.51, 3.24, and 3.60, respectively. Ultrasound variables, particularly stiffness, were good indicators of hip fracture risk. Received: 7 June 1995 / Accepted: 14 June 1996     

Comparison of Quantitative Calcaneal Ultrasound and Dual Energy X-ray Absorptiometry in the Evaluation of Osteoporotic Risk in Children with Chronic Rheumatic Diseases

Osteoporosis is a common complication in children with chronic rheumatic diseases (CRD). Although dual energy X-ray absorptiometry (DXA) is increasingly being used to determine bone mineral density (BMD) in children, it exposes the subject to ionizing radiation and does not provide a measure of true bone density; in fact, in growing bones the increase in BMD is mainly caused by the increase in bone size. In recent years, quantitative ultrasound techniques (QUS) have been used in radiation-free assessment of bone density and ``bone quality' by measurement of the ultrasound waves attenuation by bone (BUA). In the present study we made a direct comparison of BUA in the calcaneum, determined by the pediatric contact ultrasound bone analyzer (CUBA) with lumbar BMD measured by DXA, in a group of 6–18-year-old patients with CRD. The study group consisted of 53 patients affected with juvenile rheumatoid arthritis (n = 29), systemic lupus erythematosus (n = 13), and juvenile dermatomyositis (n = 11). Mean age was 13.02 ± 2.69 years. In 22 patients (19 girls, 3 boys) both DXA and CUBA were repeated after 1 year in order to assess the mean percentage rate of BMD and BUA change over this time. Both lumbar spine BMD and calcaneal BUA measurements were lower in the CRD patients compared with a control group (P < 0.001). Calcaneal BUA was significantly correlated (r = 0.83, P < 0.001) with lumbar spine BMD. Age and sex correction (Z-score) did not change the relationship between BUA and BMD (r = 0.80, P < 0.001). A significant correlation between the mean percentage of variation (Δ%) of BMD and BUA (r = 0.76, P < 0.001) was also demonstrated in the 22 patients who were evaluated prospectively. Portability, ease of use, lower cost, and absence of radiation make CUBA a promising means of evaluating BMD in children. Received: 12 December 1998 / Accepted: 13 January 2000     

Radial and Metacarpal Bone Mineral Density and Calcaneal Quantitative Ultrasound Bone Mass in Normal Japanese Women

The purpose of this study was to examine the effect of lifetime physical activity of farmers on skeletal status. Seventy-one healthy, postmenopausal women (mean age 52.3 ± 5.9 years, range 42–61 years) who worked professionally on farms were compared with 78 matched controls (mean age 51.8 ± 5.5 years, range 42–61 years). Broadband ultrasound attenuation (BUA) and speed of sound (SOS) at the os calcis were measured using an ultrasound transmission imaging system. Bone mineral density (BMD) of the lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry (DXA). Differences in BUA, SOS, and BMD between farmers and controls were expressed relative to standard deviation (SD) of the farmers. Farmers had significantly higher density values than controls (difference = 1.3 SD in the spine and 1.5 SD in the femoral neck, P < 0.0001 for both comparisons). Ultrasound values were significantly higher in the farmers compared with the controls in calcaneus (difference = 1.1 SD for BUA and 0.7 SD for SOS, P < 0.0001 for both comparisons). The difference of spine BMD, femoral neck BMD, BUA, and SOS between farmers and controls, as judged by comparison of the slopes of the regression lines, was unchanged with age and years since menopause. These results suggest that lifetime physical activity has a positive effect on bone status of postmenopausal farmers. Received: 19 March 1998 / Accepted: 7 August 1998     

The Relationship Between Childhood Growth,Bone Mass,and Muscle Strength in Male and Female Adolescents

In this population-based study, the relationship between childhood weight and height, and adolescent bone mass and muscle strength have been studied in 39 girls and 48 boys. Total body and femoral neck bone mass measurements (bone mineral content, BMC and bone mineral density, BMD) were made by dual X-ray absorptiometry. Quadriceps muscle strength was measured. Mean age at the time of measurement was 15.1 years for girls and boys. Results were individually linked to data on childhood (birth to 6 years of age) weight and height, taken from community health records. Childhood weight was found to be predictive of adolescent total body BMC (TBMC). However, this was not the case when correlating childhood weight and total body BMD (TBMD), suggesting that growth determines the size of the skeleton, whereas the density within that bone envelope is to a greater extent governed by other factors. Further, in a multiple regression model we found that the combined effect of childhood weight and height was significantly correlated with adolescent quadriceps muscle strength. Received: 25 July 1995 / Accepted: 10 December 1996     

Normal Values for Tibial Quantitative Ultrasonometry in Caucasian Children and Adolescents (Aged 6 to 19 Years)

Bone densitometry in children is a relatively new topic of interest within the field of osteoporosis. Bone densitometry techniques using an X-ray source have the disadvantage of radiation exposure. Also on some systems, motion artifacts are caused by long scan times. Tibial quantitative ultrasonometry (QUS) is ideally suited for children as it is radiation free and the interactive measurement provides real-time quality control. In this prospective study, we present data from 596 healthy children—309 girls, mean age 12.9 years (range 6.1–19.9), and 287 boys, mean age 12.3 years (range 6.1–19.6) from Rotterdam, The Netherlands. For all subjects, a short questionnaire regarding overall health was completed. To assess skeletal age, an X-ray of the left hand was taken and tibial QUS of the right tibia was performed using the SoundScan™ Compact. A statistically significant correlation was found between age and speed of sound (SOS)—r² _boys= 0.52 and r² _girls= 0.63 (both P < 0.001) and between skeletal age and SOS—r² _boys= 0.56 and r² _girls= 0.63 (both P < 0.001). In boys, significant increase of mean SOS is seen between Tanner stages II and III and between IV and V. In girls there is a significant increase of mean SOS among all Tanner stages, except stages II and III. This is the first study to present normative tibial QUS data for Caucasian children and adolescents. In this study, normative data relative to skeletal age are also provided, facilitating the implementation of this technique in children with growth disorders showing dissociation between calendar and skeletal age. Received: 20 November 1998 / Accepted: 8 March 2000     

Measuring Skeletal Changes with Calcaneal Ultrasound Imaging in Healthy Children and Adults: The Influence of Size and Location of the Region of Interest

We measured the quantitative ultrasound (QUS) parameters broadband ultrasound attenuation (BUA) and speed of sound (SOS) at the calcaneus using an ultrasound imaging device (UBIS 3000) in 698 healthy Caucasian male and female subjects (110 prepubertal, 356 pubertal/adolescent and 210 adult) between 6 and 77 years of age. The influence of different region of interest (ROI) diameters (6–20 mm) and software techniques (automatic (ROIaut), copied (ROIcop) and fixed coordinate (ROIfix) measurements) on annual rate of change, trend assessment interval (TAI; an estimate of the follow-up time required for measuring a true change), percentage of positioning errors (positioning of the ROI partly at the cortical edge or even partly beyond the calcaneus) and short-term precision error was studied. When using ROI diameters increasing from 8 to 20 mm, the annual rate of change of BUA and SOS did not change in adults, but was higher in prepubertal subjects (when subjects with positioning errors were excluded) as well as in pubertal/adolescent subjects. TAIs for BUA were shortest when using ROIaut with ROI diameters between 8 and 14 mm (TAI between 1.2 and 1.5 years for prepubertal boys and pubertal/adolescent subjects, 2.4 years for prepubertal girls, 2.7 years for postmenopausal women, and 9 years in men and premenopausal women). TAIs for SOS were 4 years or more, except for postmenopausal women (2.1 years) and prepubertal boys (3.2 years). Measurements with large ROI diameters, especially with fixed region coordinates, resulted in a high percentage of positioning errors and mostly in longer TAIs. Analysis of the short-term precision errors did not reveal these important differences between the various ROI diameters. Our results indicate that calcaneal ultrasound imaging may be useful for measuring skeletal changes in healthy children, especially with BUA, and in postmenopausal women with BUA and SOS using an automatic measurement in the region of lowest attenuation. ROI diameters of 12 mm should be used in prepubertal subjects and of 14 mm in pubertal/adolescent and adult subjects. Received: 30 October 2000 / Accepted: 13 June 2001     

Age Changes of Calcaneal Ultrasonometry in Healthy German Women

This study assessed age changes in quantitative ultrasound sonometry (QUS) in a large sample of healthy German women. Speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index (SI) of the calcaneus were measured in 1333 women (mean age 50.5 ± 11.5 years) using the Achilles ultrasonometer (Lunar Corp., Madison, WI, USA). The short-term precision in 31 adults was 0.2% for SOS, 1.2% for BUA, and 1.3% for SI. There was an overall decline of 15% for BUA, 4% for SOS, and 31% for SI between late adolescence and old age. In premenopausal women, BUA decreased only slightly (−3%), whereas postmenopausal women showed a significantly increased decline (−12%). In contrast, SOS continuously decreased from the age of 15; there was a decline of 2% from adolescence to the menopause; postmenopausal women showed a slightly larger decline (−2.5%). The SI of premenopausal women decreased by 10%, but the postmenopausal decline of almost 22% was significantly greater. SI values for premenopausal German women were comparable to those observed in the American Achilles reference population, but postmenopausal German women had significantly higher SI values of 7% due to a lower rate of aging loss. Received: 12 August 1998 / Accepted: 28 January 1999     

Lifestyle factors affecting bone ultrasonometry of the calcaneus in Japanese women

Ultrasonometry is increasingly used to assess bone characteristics. A group of 1412 women with a mean age of 57 years attended a screening examination in a Japanese city. Seventy-four percent of participants were postmenopausal. Broadband ultrasound attenuation (BUA), speed of sound (SOS), and Stiffness index (SI) of the calcaneus were measured; subjects also completed a questionnaire examining lifestyle factors; anthropometric data were recorded. Analysis showed that the strongest predictors of decreased BUA, SOS, and SI were increased age and menopausal status. Higher body mass index and current participation in exercise or sports were significant predictors of increased BUA, SOS, and SI in a multivariate model. Higher calcium intake predicted increased BUA (P= 0.004) and missing meals predicted a lower SOS (P= 0.019). This study suggests that dietary factors as well as physical activity influence bone characteristics assessed by QUS. QUS may be a suitable technique to assess the effect of lifestyle changes on bone. Received: 29 December 1998 / Accepted: 26 July 1999     

Ultrasound Measurements at the Calcaneus in Men: Differences Between Healthy and Fractured Persons and the Influence of Age and Anthropometric Features on Ultrasound Parameters

The aim of this cross-sectional study was to assess the ability of quantitative ultrasound at the calcaneus to discriminate between fractured and unfractured men, fracture probability, and the relationship of ultrasonic parameters to age and body size. The study included 224 men (age range 36–86 years) with no history of diseases or therapy affecting bone metabolism. The subjects were divided into two groups (unfractured, n= 148; fractured, n= 76) matched for age and body size. Bone status was assessed by ultrasound measurements at the calcaneus. Long-term in vitro CV% values were 0.88% for speed of sound (SOS) and 0.54% for broadband ultrasound attenuation (BUA). In vivo CV% values were 0.33% for SOS and 2.48% for BUA, while sCV% values were 4.66% and 6.58%, respectively. The following SOS/BUA values were obtained: in unfractured men, SOS = 1517.5 ± 35.3 m/s and BUA = 114.0 ± 13.3 dB/MHz; in fractured men, SOS = 1492.6 ± 24.6 m/s and BUA = 106.1 ± 11.6 dB/MHz. The differences were significant (p<0.0001). The odds ratio for BUA for all fractures was 1.05 (95% CI, 0.03–2.07) and for SOS 2.13 (95% CI, 0.77–3.49). Only the age-related decrease in SOS in unfractured men was significant (r=−0.17, p<0.05). In fractured men, weight and body mass index (BMI) were found to correlate significantly with BUA (r= 0.31, p = 0.007, r= 0.31, p = 0.007, respectively). The areas under receiver operating characteristics (ROC) curves were 0.706 for SOS and 0.665 for BUA. Ultrasound measurements at the calcaneus thus enable discrimination between fractured and healthy males. Different patterns of the relationship between age and body size in the two groups suggest the presence of other, unknown factors affecting bone status. Their identification requires further prospective studies. Received: 2 February 1998 / Accepted: 23 October 1998     

Plantar Flexion Force Is Related to Calcaneus Bone Ultrasonic Parameters in Postmenopausal Women

The aim of this report was to study the relationship between the plantar flexion strength produced by contraction of the triceps surae (gastrocnemii-soleus) muscle and the calcaneus bone parameters assessed by quantitative ultrasound in 45 healthy postmenopausal women. Plantar flexion strength was related to calcaneus broadband ultrasound attenuation (BUA) (r = 0.43, P= 0.003) and to speed of sound (SOS) (r = 0.3, P= 0.04). Plantar flexion appeared to predict ultrasonic properties, independently of body weight (R²= 19% and 9% for BUA and SOS, respectively). These results suggest that the stresses related to locomotion locally enhance bone remodeling but further studies are needed to identify the respective role of the compressive strains related to ground reaction forces at heel-strike and the muscular tensile strains applied on the calcaneus where the calcaneal tendon is inserted. Received: 2 August 1996 / Accepted: August 1997     

Imaging Ultrasonometry of the Calcaneus: Dependence on Calcaneal Area

The purpose of this study was (1) to investigate the dependence of broadband ultrasound attenuation (BUA) and speed of sound (SOS) measured in a circular region of interest (ROI) having a fixed size on calcaneal area and (2) to examine whether the normalization of ultrasonic variables for the area of the calcaneus provides better differentiation of diseased subjects from healthy individuals. Ultrasound variables were estimated in 169 healthy postmenopausal women (mean age 66.5 years, range 42–87 years) and 39 women with vertebral fractures (mean age 72.9 years, range 51–86 years). A minimum attenuation ROI, 15 mm in diameter, with a commercial imaging ultrasonometer was used. Significant relationships were found between both ultrasonic variables and calcaneal area (r²= 0.06, P < 0.001 for BUA, r²= 0.12, P < 0.0001 for SOS). Normalization of ultrasound variables (BUAn and SOSn) was based on the regression equations of the relationships among BUA, SOS, and calcaneal area. In a precision study, nine women were examined five times each to determine the errors arising from both the repositioning of the foot and selection of the calcaneal area. The reproducibility errors of BUA, SOS, BUAn, SOSn, and area were 0.87%, 0.20%, 1.07%, 0.27%, and 3.72%, respectively. Significant differences were found between the areas under the ROC curve for BUAn and BUA (area under the curve = 0.93 for BUAn versus 0.90 for BUA, P= 0.003) as well as for SOSn and SOS (area under the curve = 0.85 for SOSn versus 0.79 for SOS, P= 0.003). Normalization of ultrasound variables for calcaneal area improves the discrimination of clinical studies. Received: 7 June 1999 / Accepted: 18 January 2000     

Influence of Birth Weight on Calcaneal Bone Stiffness in Belgian Preadolescent Children

The aim of this study was to investigate the relation between birth weight and calcaneal bone stiffness in a large sample of Belgian, healthy, preadolescent children. Participants were 827 children (3.6-11.2?years, 51.6?% boys) from the Belgian cohort of the IDEFICS study. Birth weight was obtained using a parental questionnaire, and quantitative ultrasound (QUS) measurements were performed to determine calcaneal broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) using the Lunar Achilles device. Average birth weights were 3435.7?±?512.0?g for boys and 3256.9?±?471.1?g for girls. Average calcaneal QUS measurements were 89.6?±?24.0 (23.3-153.9)?dB/MHz for BUA, 1621.4?±?49.6 (1516.3-1776.5)?m/s for SOS, and 92.8?±?15.6 (49.0-163.0) for SI. Birth weight was positively associated with BUA (r?=?0.13, p?=?0.002) and SOS (r?=?-0.16, p?相似文献   

Influence of Physical Activity on Ultrasound and Dual-Energy X-ray Absorptiometry Bone Measurements in Peripubertal Girls: A Cross-Sectional Study

The aim of this cross-sectional study was to investigate whether two types of physical exercise affect the growing skeleton differently. We used calcaneal quantitative ultrasound measurements (QUS) and dual-energy X-ray absorptiometry (DXA) for measurement of bone mineral density (BMD), and to test how QUS values reflect the axial DXA values in these various study groups. A total of 184 peripubertal Caucasian girls aged 11–17 years (65 gymnasts, 63 runners, and 56 nonathletic controls) were studied. Weight, height, stage of puberty, years of training, and the amount of leisure-time physical activity were recorded. Broadband ultrasound attenuation (BUA) and sound of speed (SOS) through the calcaneus were measured. The BMD of the femoral neck and the lumbar spine were measured by DXA. The differences in mean values of bone measurements among each exercise group were more evident in pubertal than prepubertal girls. The mean BUA and SOS values of the pubertal gymnasts were 13.7% (77.8 dB/MHz versus 68.4 dB/MHz, P < 0.05) and 2.2% (1607.7 m/s versus 1572.4 m/s, P < 0.001) higher than of the controls, respectively. The mean BMD of the femoral neck in the pubertal gymnasts and runners was 20% (0.989 g/cm² versus 0.824 g/cm², P < 0.001) and 9.0% (0.901 g/cm² versus 0.824 g/cm², P < 0.05) higher than in the controls, respectively. The amount of physical activity correlated weakly but statistically significantly with all measured BMD and ultrasonographic values in the pubertal group (r = 0.19–0.35). The correlation between ultrasonographic parameters and BMD were weak, but significant among pubertal runners (r = 0.47–0.55) and controls (r = 0.39–0.42), whereas the DXA values of the femoral neck and the ultrasonographic parameters of the calcaneus did not correlate among highly physically active gymnasts. By stepwise regression analysis, physical activity accounted for much more of the variation in the DXA values than the ultrasonographic values. We conclude that the beneficial influence of exercise on bone status as measured by ultrasound and DXA was evident in these peripubertal girls. In highly active gymnasts the increase of the calcaneal ultrasonographic values did not reflect statistically significantly the BMD values of the femoral neck. Received: 28 June 1999 / Accepted: 2 November 1999     

Influence of Bone Quality on Precision of Calcaneal Ultrasonometry

This study was designed to determine the changes in precision of the ultrasound parameters speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index (SI) as a function of bone quality. The instrument used in this investigation was the LUNAR Achilles. Of the 608 female patients who had paired measurements with repositioning, 200 had t scores ≥−1 and 408 had t scores ≤−2.5, thus rendering a normal and a grossly abnormal group for comparison of precision results. It was found that the median precision error (CV%) for BUA was 1.99% for normal bone and 1.44% for abnormal bone (P= 0.02). No significant difference was obtained between median precision errors in normal and abnormal bone for the parameters SOS and SI, which were 0.23% and 0.19%, and 2.15% and 2.02%, respectively. In the interquartile range, the mean precision errors for SOS and BUA were significantly different in normal and abnormal bone: SOS was 0.25% and 0.21%, respectively, and BUA was 2.31% and 1.85%, respectively. No significant change was registered for SI. Precision error appears to decrease slightly at lower values for calcaneal variables. Received: 21 August 1996 / Accepted: 5 March 1997     

Influence of body composition on quantitative ultrasound parameters of the os calcis in a population-based sample of pre- and postmenopausal women

Body mass is known to be related to measures of bone mineral density (BMD) as well as to parameters of quantitative ultrasound (US). To examine the effect of the body compartment's fat mass and lean body mass on quantitative ultrasonic bone parameters, data from a sample of 3241 German women were analyzed. Anthropometric measures, including skinfold thickness, were obtained from standardized measurements, and fat and lean body mass were derived from classical regression formulas based on skinfold measurements. Ultrasonic bone measurements were performed on the right os calcis, and speed of sound (SOS) and broadband ultrasound attenuation (BUA) were determined. Women were grouped into pre- and postmenopausal status; postmenopausal women were further stratified into ever and never hormone-replacement user. Correlation analysis indicated lean body mass to be stronger correlated with BUA than fat mass in both pre- (r = 0.23; P= 0.0001) and postmenopausal women with (r = 0.19; P= 0.0001) and without hormone replacement therapy (HRT) (r = 0.26; p = 0.0001). SOS demonstrated very small or no associations with body mass or its components. Multiple linear regression models were used to describe the relationship among body weight, fat mass, and lean body mass on BUA after adjustment for confounding variables. Both in pre- and postmenopausal women lean body mass was more strongly related to BUA than fat mass. However, body mass measures explained only small amounts of the overall variance in BUA (R²= 1–3% in premenopausal women; R²= 1% postmenopausal with HRT; R²= 4–5% in postmenopausal women without HRT). In conclusion, the strong influence of body mass and its components previously reported for BMD was not observed for quantitative ultrasonic bone parameters. Received: 5 January 1999 / Accepted: 1 July 1999     

Quantitative ultrasound imaging of the calcaneus: precision and variations during a 120-Day bed rest

This study reports on the precision and variation of quantitative ultrasound (US) parameters [broadband ultrasonic attenuation (BUA) or slope of the frequency-dependent attenuation in dB/MHz and speed of sound (SOS m/second)] after 120 days of continuous bed rest in six normal male volunteers. Quantitative US was measured at the calcaneus using a new US bone imaging scanner. The measurements were carried out on both heels at approximately 2-week intervals. The short-term precision was 0.31% for SOS and 2.8% for BUA. The long-term precision was 0.58% for SOS, 4.7% for BUA. A significant decrease of SOS values of −26 m/second (P < 0.0001) for the right heel and −17 m/second (P < 0.05) for the left heel was found at the group level. In terms of percentage change this represents −1.7% for the right heel and −1.1% for the left heel. These percentage decrements were 3.5–5.5 times that of the short-term precision and 2–3 times that of the long-term precision of the technique. At the individual level, the decrease of SOS was statistically significant (P < 0.05) or marginally significant (P < 0.1) for four out of 6 subjects. For 2 other subjects, similar trends were observed, but without reaching statistical significance. BUA did not change significantly during follow-up. These results are consistent with previous findings on changes of ultrasonic properties from the calcaneus during aging, pregnancy, or therapy, showing that calcaneus SOS is a valuable index of bone loss. These preliminary data suggest that prolonged exposure to simulated weightlessness may lead to a lower SOS, which then could be used for the follow-up of bone demineralization occurring during long-term space flights. Received: 5 January 1999 / Accepted: 1 July 1999     

The impact of low-saturated fat,low cholesterol diet on bone properties measured using calcaneal ultrasound in prepubertal children

To analyze the effects of low-saturated fat, low-cholesterol diet on bone in healthy children, calcaneal ultrasound measurements were obtained in 139 subjects (71 girls, 68 boys; mean age 8 years, SD 0.5), who were recruited from the STRIP (Special Turku Coronary Risk Factor Intervention Project) trial. Speed of sound (SOS), broadband ultrasound attenuation (BUA), and quantitative ultrasound index (QUI) values were determined at the dominant heel using a Hologic Sahara scanner. Values were compared with anthropometry and mean, energy-adjusted dietary intakes (absolute intake/1000 kcal) of fat, carbohydrates, protein, cholesterol, calcium, fiber, and the polyunsaturated to saturated fatty acid ratio derived from 4-day food diaries kept once a year between the ages of 2-7 years. The intakes were also analyzed separately at each time point. The BUA, SOS, and QUI values of the intervention children (n = 90) and the control children (n = 49) were similar. No gender differences were found. BUA correlated with age (r = 0.26, P<0.01), height (r = 0.19, P<0.05), and weight (r = 0.22, P<0.05). QUI correlated with mean intake of fat (r = 0.19, P<0.05) and carbohydrate (r = -0.22, P<0.05), SOS with mean intake of cholesterol (r = 0.18, P<0.05), and BUA with mean intake of carbohydrate (r = -0.22, P<0.05). The intakes of fat and cholesterol were lower (P<0.001) and intakes of protein and carbohydrates higher (P<0.01) in the intervention children, but the intakes of calcium were similar. The differences in the dietary intakes persisted throughout the study period. We conclude that dietary counseling aimed at reducing risk of atherosclerosis in later life does not decrease dietary intake of calcium or diminish the calcaneal ultrasound values in the intervention of children in this study. However, since this study is cross-sectional and only one measurement of bone is used, further studies are needed to draw further conclusions about the influence of dietary counseling on bone health.     

Evaluation of a New Calcaneal Quantitative Ultrasound System and Determination of Normative Ultrasound Values in Southern Chinese Women

Quantitative ultrasound (QUS) assessment at the calcaneus has been found to be a safe and reliable method for evaluating skeletal status. The present study aimed at evaluating the precision of the Sahara bone ultrasound densitometer and to determine the normative QUS data in healthy southern Chinese women. Broadband ultrasound attenuation (BUA), speed of sound (SOS) and qualitative ultrasound index (QUI) were determined. The long-term in vitro precision of the Sahara machine over 6 months was 4.6% for BUA and 0.39% for SOS. The short-term in vivo precision was 3.2 ± 1.3% for BUA, 0.3 ± 0.2% for SOS and 1.8 ± 1.0% for QUI. The standardized precision for BUA, SOS and QUI was 4.4, 3.8 and 2.2 respectively. The normative data were determined in 1086 healthy subjects. Postmenopausal women had significantly lower BUA, SOS and QUI levels than the premenopausal women. Significant negative correlations were observed between QUS indices and age. Bone mineral density (BMD) assessments was performed on 349 of these subjects. BUA correlated significantly with lumbar spine BMD (r; = 0.326) and femoral neck BMD (r= 0.395). Similar correlations were observed between SOS, QUI and BMD, with r values ranging between 0.446 to 0.522. Despite the fact that Chinese women have significantly lower BMD values than Caucasian women, the mean BUA values for pre- and postmenopausal Chinese women (73 ± 18 and 59 ± 18 dB/MHz respectively) were almost the same as those reported for Caucasian womeo. These normative data will be useful in the assessment of southern Chinese women with fracture risk. Received: 7 May 1998 / Accepted: 18 August 1998     

Comparison of Six Calcaneal Quantitative Ultrasound Devices: Precision and Hip Fracture Discrimination

Quantitative ultrasound (QUS) is now accepted as a useful tool in the management of osteoporosis. There are a variety of QUS devices clinically available with a number of differences among them, including their coupling methods, parameter calculation algorithms and sites of measurement. This study evaluated the abilities of six calcaneal QUS devices to discriminate between normal and hip-fractured subjects compared with the established method of dual-energy X-ray absorptiometry (DXA). The short-term and mid-term precisions of these devices were also determined. Thirty-five women (mean age 74.5 ± 7.9 years) who had sustained a hip fracture within the past 3 years, and 35 age-matched controls (75.8 ± 5.6 years) were recruited. Ultrasound measurements were acquired using six ultrasound devices: three gel-coupled and three water-coupled devices. Bone mineral density was measured at the hip using DXA. Discrimination of fracture patients versus controls was assessed using logistic regression analysis (expressed as age- and BMI-adjusted odds ratios per standard deviation decrease with 95% confidence interval) and receiver operating characteristics (ROC) curve analysis. Measurement precision was standardized to the biological range (sCV). The sCV ranged from 3.14% to 5.5% for speed of sound (SOS) and from 2.45% to 6.01% for broadband ultrasound attenuation (BUA). The standardized medium-term precision ranged from 4.33% to 8.43% for SOS and from 2.77% to 6.91% for BUA. The pairwise Pearson correlation coefficients between different devices was highly significant (SOS, r= 0.79–0.93; BUA, r= 0.71–0.92). QUS variables correlated weakly, though significantly, with femoral BMD (SOS, r= 0.30–0.55; BUA, r= 0.35–0.61). The absolute BUA and SOS values varied among devices. The gel-coupled devices generally had a higher SOS than water-coupled devices. Bone mineral density (BMD) and BUA were weakly correlated with weight (r= 0.48–0.57 for BMD and r= 0.18–0.54 for BUA), whereas SOS was independent of weight. All the QUS devices gave similar, statistically significant hip fracture discrimination for both SOS and BUA measures. The odds ratios for SOS (2.1–2.8) and BUA (2.4–3.4) were comparable to those for femoral BMD (2.6–3.5), as were the area under the curve (SOS, 0.65–0.71; BUA, 0.62–0.71; BMD, 0.65–0.74) from ROC analysis. Within the limitation of the sample size all devices show similar diagnostic sensitivity. Received: 2 February 2000 / Accepted: 1 May 2000