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1.
Summary A method of measuring ultrasonic propagation in the os calcis was devised for assessing bone properties in humans, Speed-of-sound (SOS) and broadband ultrasound attenuation (BUA) were measured using broadband acoustic pulses transmitted and received by a pair of focused transducers. The transducers are mounted coaxially in a water tank with the subject's heel in between. Reproducibility of results in an adult male was 10% for the BUA and 1.2% for the SOS. Both SOS and BUA changed when the transmission path through the os calcis was varied. For a population of normal male subjects, SOS and BUA were correlated with densitometry results on the os calcis, but less well correlated to area density at remote sites.  相似文献   

2.
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  相似文献   

3.
Dual energy x-ray absorptiometry (DXA) was used to measure bone mineral density (BMD) of the lumbar spine and proximal femur (neck, Ward's triangle, and trochanter) in 417 normal women (aged 20–79) living in São Paulo, Brazil. Bone density decreased with age at all sites. At the spine, the greatest decrease occurred during the sixth decade, with an average 11.4% bone loss compared with the previous decade. Stratifying the subjects according to menopausal status revealed that the fastest bone occurred at the time around the menopause (ages 45–60) when the rate of bone loss (-0.66%/year) was almost twice as rapid as in postmenopausal women (-0.39%/year). Although significant linear rates of bone loss were detected in all proximal femur sites before the menopause, a menopause-dependent pattern was less evident that at the spine. Lifetime rates of bone loss at the appendicular skeleton were-0.43,-0.62, and-0.35%/year at the femoral neck, Ward's triangle, and trochanteric area, respectively. After the menopause, BMD declined with menopausal age at all sites, although the rate of bone loss was faster at the femoral neck (-0.62%/year) and Ward's triangle (-0.84%/year) than at the spine-0.49%/year). The results are consistent with the notion that in women, the fastest bone loss occurs at the time round the menopause, most likely consequent to ovarian failure; and that faster rates of bone loss are detected at the proximal femur than at the lumbar spine in late postmenopausal women.  相似文献   

4.
Summary Bone ultrasound attenuation of the calcaneus, and vertebral and femoral bone density measured by dual photon absorption were determined in 22 women with osteoporosis, 10 women with hip fractures, and 29 normal, age-matched controls to determine the utility of the ultrasound technique as an indicator of axial osteopenia. Vertebral and femoral neck density and bone ultrasound attenuation were significantly decreased (P<0.01) in the women with osteoporosis and those with hip fractures. The sensitivity and specificity of bone ultrasound attenuation was 80% at a value of 50 dB/MHz. At 90% specificity the sensitivity of bone ultrasound attenuation was 65%. The results of this pilot study suggest that ultrasound attenuation, a safe, simple, and radiation-free procedure, may be utilized as an indicator of decreased axial bone mass.  相似文献   

5.
Introduction Previous studies suggesting different effects of diet on post-menopausal bone loss may have given conflicting results because they sometimes failed to exclude confounding conditions or used imprecise methodology.Design To identify dietary determinants of bone loss from the lumbar spine after menopause in women not taking hormone replacement who developed no evidence of spondylotic or sclerotic degenerative disease, forty-three women were followed with repeated (mean = 12) measurements of bone mineral density (BMD) at L2–4 for 11–14 years. Eleven developed evidence suggestive of degenerative disease and were excluded. Diet was assessed at the beginning of the study and 2.5 years later using 3-day and 7-day periods of weighed intakes. Nutrients estimated were: carbohydrate, fat, protein, fibre, calcium, magnesium, iron, phosphorus, copper, zinc and six vitamins. We tested the ability of diet to predict post-menopausal bone loss using stepwise regression.Results Each woman’s BMD change was described by a single coefficient after log transformation of the BMD data. The best model for BMD loss including dietary factors alone had two significant determinants: daily energy or protein (p=0.0003) intake was adverse, while dietary iron (p=0.002) was predictive of bone maintenance, an effect that persisted if iron was expressed as a ratio to energy intake. Adding body mass index to the model increased the goodness of fit (R 2adj rose from 0.33 to 0.42) without affecting the statistical significance of the dietary determinants.Conclusions Diet may influence bone loss after menopause, with dietary iron (or an associated factor) possibly having a protective effect on bone at the spine.  相似文献   

6.
Ultrasound transmission measurement through the os calcis is an emerging technique and a promising clinical tool for early assessment of osteoporosis. However, several previous studies showed that broadband ultrasonic attenuation (BUA) is sensitive to small variations in bone mass or structure. The os calcis is an inhomogeneous bone and therefore, the attenuation depends on the location in the os calcis. BUA distribution within the os calcis can be measured by rectilinear scanning over the entire bone. We used a mechanical scanning device with both unfocused and focused transducers. The spatial resolution of these was about 25 mm and 4 mm, respectively. There was good agreement (r=0.97) between the results with unfocused and focused transducers. In addition, imaging the variations of BUA is possible with the focused transducers, and high quality images are obtained. These images permit the selection of optimal regions of interest for ultrasound attenuation measurement.  相似文献   

7.
We investigated 2-year longitudinal changes of bone mineral density (BMD) in lumbar spine and proximal femur in 64 Japanese women aged 38–67. Forty subjects were premenopausal (mean age 44.9) and 24 postmenopausal (mean age 54.6) at enrollment of the study. Six subjects experienced menopause during the 2-year study period and were defined as the perimenopausal group. Measurements of BMD were performed using dual-energy X-ray absorptiometry at L2–4, femoral neck, greater trochanter, and Ward's triangle. Paired t test revealed no significant decrease in BMD at any site in the premenopausal group. Significant annual decrease in BMD was observed in the perimenopausal group at L2–4, femoral neck, and greater trochanter. A similar tendency was observed in Ward's triangle, but did not reach statistical significance. In the postmenopausal group, significant decrease in BMD was found at the proximal femur, but not at L2–4. Significant inverse correlation between age and change rate of BMD was found at L2–4, but not at the proximal femur, in premenopausal women. In postmenopausal women, there was a significant association between body weight (BW) change and change rate in BMD at L2–4, femoral neck, or greater trochanter. This association was not found in the premenopausal group. These results suggest that effect of menopause on BMD may be different in individuals and sites of the skeleton. BW change may affect change in BMD in postmenopausal women. However, the limited variability in both BW and BMD changes among premenopausal women in this study may explain the poor association between change in BW and change in BMD in the premenopausal group. As individual differences in each group is considerably large, annual measurements of BMD may be necessary to find possible candidates for early intervention.  相似文献   

8.
To assess the usefulness of the measurement of the os calcis by ultrasound, a method that probably reflects bone quality as well as density, we have studied 54 women with hip fracture of the proximal femur and a control group. Ultrasound evaluation of the os calcis [broadband ultrasound attenuation (BUA), speed of the sound (SOS), and a combined index (stiffness)], and bone mineral density (BMD) determination over the proximal femur by dual X-ray absorptiometry (DXA) were performed. Weight, BMD, and ultrasound values in the hip fracture patients were significantly lower than controls (P<0.001). The Z-scores for BUA and stiffness were not different than that for femoral neck. Ward's triangle or trochanteric BMD (between-1.7 and -1.5). The odds ratios determined by receiver-operating characteristics (ROC) analysis were greater at the femoral neck (25.1) and BUA (24.4). Intermediate values were found at stiffness (16.9), Ward's triangle (12.8), and trochanter (11.1), and lower values were obtained at SOS (4.2). In turn, patients with trochanteric hip fractures had a significantly lower femoral neck and Ward's triangle BMD, stiffness, and BUA than patients with cervical hip fractures. Comparing a subgroup of 30 women with hip fractures without vertebral fractures with an age-matched group of 87 women with osteoporotic vertebral fractures, both groups were of similar weight and BMD but all ultrasound values were significantly lower in the hip fractures compared with vertebral fracture patients (P<0.05-P<0.01). Our findings suggest that in women with hip fractures, ultrasound evaluation of the os calcis has diagnostic sensitivity comparable to DXA of the femur and could be useful to predict hip fracture risk. Ultrasound values are lower in hip fractures compared with vertebral fracture, age-matched women and in older compared with younger hip fracture patients.  相似文献   

9.
Summary Total body bone mass (TBBM), axial bone mass (trunk=chest and spine), and peripheral bone mass (arms and legs) were determined in 258 normal, slow bone mass loser, postmenopausal women, as determined by previous biochemical studies, in order to study the degree of bone mass reduction due to menopause. The subjects of this study were divided into 5-year groups on a year-since-menopause basis. The first group corresponded to 1–5 years since menopause, and the last group to 25 years or over since menopause. An important and significant reduction in trunk bone mass (-12.3%, P<0.001) and TBBD (-5.8%, P<0.002), without changes in head, arms, and legs was observed in the first 5-year group. In the next 5-year group, a significant reduction was observed in all body areas, but at a higher rate in the peripheral skeleton (-9% in arms and -7.3% in legs). A slow down in bone mass loss was observed in the period between 10 and 25 years since menopause. These values became significant again after 25 years since menopause at the axial (-28.9%, P<0.001) and TBBD (-20.3%, P<0.05) level. Aside from providing percentages of bone mass reduction with respect to age and time since menopause, these data also indicate that measurements of specific body areas may not be extrapolated to others due to different loss in different body areas, and that there is a marked bone loss rate in the axial skeleton in the first 5 years since menopause.  相似文献   

10.
Age changes in the bone mineral of the lumbar spine in normal women   总被引:3,自引:0,他引:3  
Summary The bone mineral content (BMC) and the bone mineral areal content (BMAC) were determined with dual-photon absorptiometry in the third lumbar vertebra in a random sample of 214 women between 35 and 80 years of age in the city of G?teborg, Sweden. A continuous aging decrease (1%/year) of both the BMC and the BMAC was noted after age 35. The rate at which bone loss occurred was similar for all age groups when analyzed by 5 year intervals. No clear acceleration of bone loss was noted around the usual time of the menopause.  相似文献   

11.
中日女性超声骨密度测定对比研究   总被引:2,自引:0,他引:2       下载免费PDF全文
目的 比较中日女性间的骨密度差异,探讨中国女性骨质疏松诊断标准。方法 采用定量超声衰减技术(BUA)测定114例健康女性,采取骨强度值与同类群日本女性相对比分析。结果 与同类群日本女性相比,中国女性骨密度值总体较低,但在统计学上无明显差异。结论 中国女性的骨质疏松诊断标准可参照日本女性标准建立。  相似文献   

12.
An ultrasound transmission scanning system was constructed to makein vivo parametric images of the acoustic properties of the heel. Broadband ultrasonic attenuation (BUA) images were obtained in transmit mode by using a pair of broadband focused transducers (center frequency 0.5 MHz, diameter 29 mm, focus 50 mm) immersed in a water bath at room temperature. With these characteristics, the theoretical beam width at the focus was approximately 5 mm. The total duration of the acquisition period was 3 minutes. Comparison of the BUA image and the radiograph of the calcaneus was possible in one case and showed that all the anatomical details could be identified. The images reported here demonstrate the wide range of BUA found in both the whole bone and within a ROI centered in the posterior part of the bone thus reinforcing the idea of tremendous heterogeneity of the acoustic properties of bone. This suggests that the accurate control of the position of the measurement site is of the utmost importance for between-subject comparison and for repetitive measurements. We proposed a new method, the likelihood image, as an efficient way of highlighting the regions of the image suspected to be subject to waveform distortion. It could be used to guide the selection of the optimal measurement site. Our results suggest that ultrasound parametric imaging has the potential for enhancing the current ultrasound technique by (1) allowing reproducible, repetitive measurements, (2) permitting the selection of similar optimal measurement sites in all subjects, and (3) avoiding accuracy erros due to wave-form distortion.  相似文献   

13.
We assessed the impact of various forms of spinal degenerative joint disease (DJD) on bone mineral density (BMD) measured by quantitative computed tomography (QCT) and dual X-ray absorptiometry (DXA) in a group of postmenopausal women. Lateral (T4-L4) and AP (L1-L4) spinal radiographs were reviewed for fracture and DJD in 209 women (mean age 62.6±6.7). The severity of DJD findings was graded as 0,1, or 2 on the lumbar films, except for vertebral osteophytes which were graded from 0 to 3. Vertebral fractures were defined semiquantitatively as approximately 20% reduction in anterior, middle, or posterior vertebral height. BMD was measured in all subjects by QCT and DXA, including posteroanterior DXA (PA-DXA), lateral DXA (L-DXA) and midlateral DXA (mL-DXA). When BMD was measured by QCT and mL-DXA in the 168 women without fractures, no significant differences were found between women with and those without DJD. However, BMD by PA-DXA was significantly higher in women with DJD changes, particularly when osteophytes were present at the vertebral bodies or facet joints. BMD by L-DXA was less affecied by DJD. For this measurement a significant increase in BMD was only noted in subjects with vertebral osteophytes. Multivariate analysis of variance (MANOVA) showed that BMD by QCT and mL-DXA was not affected by DJD. In contrast, for all women, BMD by PA-and L-DXA was affected more by DJD than by fracture status. Chi-square testing demonstrated no significant relationships between vertebral fractures and any of the DJD changes. We conclude that QCT and mL-DXA are superior to PA-DXA and L-DXA in detecting bone loss in patients with DJD. Thus, for these patients, BMD assessment by QCT or mL-DXA may be advisable.  相似文献   

14.
To compare heel ultrasound values with bone densitites at different measurement sites as determined by single photon absorptiometry (SPA) and dual-energy X-ray absorptiometry (DXA) in long-term users of estrogen replacement therapy (ERT), we analyzed data from 30 users of estradiol implants (mean duration of treatment 16 years) and 32 non-users, comprising 28 complete age-matched pairs. The precision errors in vivo of ultrasound measurements were 0.18%, 1.3% and 1.5% for speed of sound (SOS), broadband ultrasound attenuation (BUA) and stiffness index, respectively. In the controls, ultrasound parameters correlated well with values from SPA and DXA measurements (r=0.51–0.63,p<0.004). In long-term users of ERT, however, measurements with ultrasound did not correlate with DXA in the spine and hip (r=0.01–0.31, NS) but correlated well with SPA in the forearm (r=0.47–0.66,p<0.009). Implant users, compared with non-users, had small and just significantly different values when measured by ultrasound (at most 12%,p=0.03–0.04) but significantly higher bone mineral densities (18%–25%,p=0.0001–0.01) in the forearm, spine and hip when measured by SPA or DXA. Data indicated that a substantial proportion of long-term users of estrogen may be non-responders concerning the effect of estrogen on bone qualities expressed in heel ultrasound values. In a multivariate regression analysis the effect of increasing age and increasing treatment duration were both negative for the ultrasound parameters. This is in contrast to our previous finding for bone density parameters in which the negative effect of increasing age was more than compensated by the positive effect of increasing treatment duration. Heel ultrasound correlated poorly with DXA measurement of axial bone density in long-term estrogen users. It has been stated that ultrasound measurements of bone status represent architecture and structure independently of bone mass. If so, then longterm ERT seems, in a substantial proportion of women, to preserve the bone mass and density better than the structure of the bone. Thus, the present study demonstrates a situation where ultrasound determinations can not simply be extrapolated to reflect the mineral density of the central skeleton.  相似文献   

15.
Summary Two hundred and thirty women aged 45–66 years were divided into three groups according to their menopausal status and were followed to assess the changes in vertebral bone mineral density (BMD). These included 71 premenopausal, 42 perimenopausal, and 117 postmenopausal women. Menopausal status was assessed through menstrual history and plasma concentrations of 17 estradiol and luteinizing hormone. BMD was measured by dual photon absorptiometry between 2 and 5 times over an average period of 27 months, and annual rates of changes were calculated by linear regression. BMD decreased significantly (P<0.0001) in the three groups during the follow-up. Mean (±SD) annual rate of change was-0.79±1.5% for premenopausal,-2.35±1.5% for perimenopausal, and-1.24±1.5% for postmenopausal women. There was no difference in the rates of bone loss between the perimenopausal group and the postmenopausal group within 3 years after menopause (1–2 years:-2.34±2.1%; 2–3 years:-1.9±1.5%). Thereafter, rates decreased exponentially with time since menopause to fall out at the same level as the premenopausal level. These longitudinal data indicate that vertebral bone loss begins before menopause and accelerates sharply during menopause to decline exponentially with time after 3 years.  相似文献   

16.
Long-term precision, as well as reproducibility, is important for monitoring bone mineral density (BMD) alteration in response to aging or therapy. In order to investigate which bone densitometry and which skeletal site are clinically useful for monitoring bone mass, we examined the standardized long-term precision of several bone density measurements in 83 healthy Japanese women. Annual BMD measurements were performed for 5 or 6 years using dual X-ray absorptiometry (DXA) on the lumbar spine, radius (EXP5000) and calcaneus (HeelScan); peripheral quantitative computed tomography (pQCT) on the radius (Densiscan1000); and quantitative ultrasound (QUS) on the calcaneus (Achilles+). The long-term precision error for the individual subject was given by the standard error of estimate (SEE), and the standardized long-term precision was defined as the percentage coefficient of variation (CV%) divided by the percentage ratio of the annual bone-loss rate. Based on the CV% of spinal DXA, speed of sound (SOS) and diaphyseal pQCT showed significantly higher precision than others, while radial ultradistal (UD) DXA and heel DXA showed significantly lower precision. The long-term precision errors of other measurements were statistically the same as that of the spinal DXA. The spinal DXA, the radial DXA, and pQCT at both the distal metaphysis and diaphysis showed high rates of annual bone loss. The radial trabecular BMD (pQCT) was significantly higher than that of spinal DXA. The annual rates of bone loss of QUS and of heel DXA were significantly lower than that of spinal DXA. Taken together, standardized long-term precision was obtained in the spinal DXA and radial pQCT. In conclusion, spinal DXA and radial pQCT were considered the most useful monitoring method for osteoporosis, while QUS was considered less useful.  相似文献   

17.
Rheumatoid arthritis (RA) is a common chronic inflammatory disease and periarticular osteoporosis or osteopenia of the inflamed hand joints is an early feature of RA. Quantitative measurement of hand bone loss may be an outcome measure for the detection of joint destruction and disease progression in early RA. This systematic review examines the published literature reporting hand bone mass in patients with RA, particularly those using the dual X-ray absorptiometry (DXA) methods. The majority of the studies reported that hand bone loss is associated with disease activity, functional status and radiological progression in early RA. Quantitative measurement of hand bone mineral density by DXA may be a useful and practical outcome measure in RA and may be predictive for radiographic progression or functional status in patients with early RA.  相似文献   

18.
19.
了解三种方法诊断骨质疏松症(OP)之间的关系。方法应用双能X线吸收法(DXA)和单光子吸收法(SPA)及定量超声(QUS),同时随机测量294例受试者腰椎后前位和侧位、左侧髓部和前臂骨矿密度(BMD)及右侧胫骨超声速度(SOS)。结果DXA和SPA测量桡骨OP的检出率分别为25.9%和21.4%,DXA测量腰椎后前位、侧位、侧位兴趣区、Ward’s区和股骨颈OP检出率分别为16.0%、22.8%、26.2%、19.4%和4.42%,QUS的OP检出率为17.7%。三种方法及不同部位之间的测量结果呈显著相关(r=0.494~0.967,P<0.01)。DXA测量前臂1/3处BMD显著高于SPA。诊断OP的齐同率DXA各部位相互之间平均为40.1%±15.5%,DXA与SPA平均为48.4%±19.0%,QUS与DXA和SPA平均为38.8%±10.2%,各平均值之间无显著差异。结论OP的检出率取决于受检部位,腰椎侧位兴趣区和挠骨是检出率最高的部位,股骨颈和尺骨是最低的部位。SPA与DXA测量前臂BMD高度相关,诊断结果无显著性差别。  相似文献   

20.
We have performed a 2-year prospective double-masked study to determine whether the bisphosphonate pamidronate can prevent bone loss in postmenopausal women and its optimal dosage regimen. One hundred and twenty-one such women (mean ± SD age 57.6±3.4 years; mean ± SD time since menopause 7.5±3.5 years) were randomized to receive either oral pamidronate (300 mg/day) for 4 weeks every 4 months (group A), oral pamidronate (150 mg/day) for 4 weeks every 2 months (group B) or identical placebo capsules (group C). Bone mineral density (BMD) measurements at the lumbar spine and proximal femur were performed at baseline and at 6-month intervals for 2 years using dual-energy X-ray absorptiometry. BMD at the lumbar spine (L2–4) increased significantly in groups A and B after 2 years of treatment (mean ± SD 2.8±2.1% and 3.0±2.9% respectively, bothp<0.001) but decreased in the placebo group (–1.6±3.1%,p<0.01). Identical results were seen for BMD at the femoral neck, which increased significantly in groups A and B after 2 years of treatment (1.2±2.3% and 1.3±2.9% respectively, bothp<0.05) but decreased in the placebo group (–1.9±3.9%,p<0.05). There were significant differences over 2 years between the groups at all anatomical sites (lumbar spine, femoral neck and trochanteric region, allp<0.001; Ward's triangle,p<0.01). However, there were no significant differences between groups A and B, suggesting that the two treatment regimens were equally effective in conserving BMD. There were, however, marked differences in tolerability between the two treatment regimens: 13 women (34%) in group A withdrew from the study because of side-effects, but only 5 women (12%) in group B, which was comparable with placebo. These data demonstrate that intermittent oral pamidronate will prevent bone loss from the lumbar spine and proximal femur of postmenopausal women, and that the more frequent but lower dose regimen is well tolerated.  相似文献   

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