***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: BACKGROUND Quantitative ultrasound of bone is a new radiation-free technique that measures bone mass and may assess bone quality . Retrospective studies have suggested that low-bone ultrasound of the calcaneus is associated with an increased risk for hip and other fractures in older women . OBJECTIVES To establish the utility of calcaneal quantitative ultrasound of bone for the prediction of fractures and to compare quantitative ultrasound of bone with bone mineral densitometry by performing a prospect i ve cohort study within the Study of Osteoporotic Fractures . SUBJECTS AND METHODS We studied 6189 postmenopausal women older than 65 years of 4 US clinical centers .  Broadb and  ultrasound attenuation ( BUA ) , a measurement of the differential attenuation of sound waves transmitted through the calcaneus , and bone mineral density of the calcaneus and hip were measured . Subsequent hip and other nonspine fractures were documented during a mean follow-up of 2.0 years . RESULTS In age- and clinic-adjusted analyses , each SD reduction in calcaneal BUA was associated with a doubling of the risk for hip fractures ( relative risk [ RR ] , 2.0 ; 95 % confidence interval [ CI ] , 1.5 - 2.7 ) ; a similar relationship was observed with bone mineral density of the calcaneus ( RR , 2.2 ; 95 % CI , 1.9 - 3.0 ) and femoral neck ( RR , 2.6 ; 95 % CI , 1.9 - 3.8 ) . After adjustment for bone mineral density of the femoral neck , BUA was still associated with an increased risk for hip fracture ( RR , 1.5 ; 95 % CI , 1.0 - 2.1 ) . Intertrochanteric fractures in particular were strongly associated with a low BUA measurement ( RR , 3.3 ; 95 % CI , 2.0 - 5.5 ) . CONCLUSIONS Broadb and ultrasound attenuation predicts the occurrence of fractures in older women and is a useful diagnostic test for osteoporosis . The strength of the association between BUA and fracture is similar to that observed with bone mineral density BACKGROUND The ability of ultrasonographic measurements to discriminate between patients with hip fracture and age-matched controls has until now been tested mainly through cross-sectional studies . We report the results of a prospect i ve study to assess the value of measurements with ultrasound in predicting the risk of hip fracture . METHODS 5662 elderly women ( mean age 80.4 years ) had both baseline calcaneal ultrasonography measurements and femoral radiography ( dual-photon X-ray absorptiometry , DPXA ) to assess their bone quality . Follow-up every 4 months enabled us to identify incident fractures . 115 hip fractures were recorded during a mean follow-up duration of 2 years . FINDINGS Low calcaneal ultrasonographic variables ( obtained from measurements of broadb and ultrasound attenuation by , and speed of sound through the bone ) were able to predict an increased risk of hip fracture , with similar accuracy to low femoral bone mineral density ( BMD ) obtained by DPXA . The relative risk of hip fracture for 1 SD reduction was 2.0 ( 95 % CI 1.6 - 2.4 ) for ultrasound attenuation and 1.7 ( 1.4 - 2.1 ) for speed of sound , compared with 1.9 ( 1.6 - 2.4 ) for BMD . After control for the femoral neck BMD , ultrasonographic variables remained predictive of hip fracture . The incidence of hip fracture among women with values above the median for both calcaneal ultrasound attenuation and femoral neck BMD was 2.7 per 1000 woman-years , compared with 19.6 per 1000 woman-years for those with values below the median for both measures . INTERPRETATION Ultrasonographic measurements of the os calcis predict the risk of hip fracture in elderly women living at home as well as DPXA of the hip does , and the combination of both methods makes possible the identification of women at very high or very low risk of fracture Abstract : In this prospect i ve study we investigated the predictive value of quantitative ultrasound ( QUS ) measurements and other potential predictors of osteoporotic fractures in the elderly . During a 1-year period , 710 participants ( 132 men and 578 women ) , aged 70 years and older ( mean age ± SD : 82.8 ± 5.9 ) , were recruited from seven homes and apartment houses for the elderly .  QUS measurements ( broadb and ultrasound attenuation ( BUA ) and speed of sound ( SOS ) )  were assessed with a clinical bone densitometer . A structured question naire was used to collect information on other potential predictors . Follow-up of fractures was done each half year by telephone interviews . During the study period ( median follow-up 2.8 years , maximum 3.7 years ) , 30 participants had a first hip fracture and 54 suffered from a first other nonspinal fracture . Cox regression analyses , adjusted for age and sex , showed that the relative risk ( RR ) of hip fracture for each st and ard deviation reduction was 2.3 ( 95 % CI , 1.4–3.7 ) for BUA and 1.6 ( 95 % CI , 1.1–2.3 ) for SOS . Slightly weaker relationships were found for any fracture ( BUA : RR , 1.6 ; 95 % CI , 1.2–2.1 ; SOS : RR , 1.3 ; 95 % CI , 1.0–1.6 ) . Multivariable analyses identified low BUA values and immobility as the strongest predictors for hip fractures and any fracture . Female gender proved to be the strongest predictor for other nonspinal fractures . It can be concluded that QUS measurements can predict the risk for hip fracture and any fracture in elderly people Abstract .The World Health Organization ( WHO ) criteria for the diagnosis of osteoporosis are mainly applicable for dual X-ray absorptiometry ( DXA ) measurements at the spine and hip levels . There is a growing dem and for cheaper devices , free of ionizing radiation such as promising quantitative ultrasound ( QUS ) . In common with many other countries , QUS measurements are increasingly used in Switzerl and without adequate clinical guidelines . The T-score approach developed for DXA can not be applied to QUS , although well-conducted prospect i ve studies have shown that ultrasound could be a valuable predictor of fracture risk . As a consequence , an expert committee named the Swiss Quality Assurance Project ( SQAP , for which the main mission is the establishment of quality assurance procedures for DXA and QUS in Switzerl and ) was m and ated by the Swiss Association Against Osteoporosis ( ASCO ) in 2000 to propose operational clinical recommendations for the use of QUS in the management of osteoporosis for two QUS devices sold in Switzerl and . Device-specific weighted " T-score " based on the risk of osteoporotic hip fractures as well as on the prediction of DXA osteoporosis at the hip , according to the WHO definition of osteoporosis , were calculated for the Achilles ( Lunar , General Electric , Madison , Wis. ) and Sahara ( Hologic , Waltham , Mass. ) ultrasound devices . Several studies ( totaling a few thous and subjects ) were used to calculate age-adjusted odd ratios ( OR ) and area under the receiver operating curve ( AUC ) for the prediction of osteoporotic fracture ( taking into account a weighting score depending on the design of the study involved in the calculation ) . The ORs were 2.4 ( 1.9–3.2 ) and AUC 0.72 ( 0.66–0.77 ) , respectively , for the Achilles , and 2.3 ( 1.7–3.1 ) and 0.75 ( 0.68–0.82 ) , respectively , for the Sahara device . To translate risk estimates into thresholds for clinical application , 90 % sensitivity was used to define low fracture and low osteoporosis risk , and a specificity of 80 % was used to define subjects as being at high risk of fracture or having osteoporosis at the hip . From the combination of the fracture model with the hip DXA osteoporotic model , we found a T-score threshold of –1.2 and –2.5 for the stiffness ( Achilles ) determining , respectively , the low- and high-risk subjects . Similarly , we found a T-score at –1.0 and –2.2 for the QUI index ( Sahara ) . Then a screening strategy combining QUS , DXA , and clinical factors for the identification of women needing treatment was proposed . The application of this approach will help to minimize the inappropriate use of QUS from which the whole field currently suffers We studied 336 elderly white women , of whom 22 had previously suffered a hip fracture and 22 had previously suffered a vertebral fracture . All subjects were 60 years old or older with a mean age of 73.7 years .  Measurements of ultrasonic transmission velocity ( UTV ) , broad-b and ultrasonic attenuation ( BUA ) and stiffness ( STF )  were made at the os calcis using a Lunar Achilles ultrasound device .  Measurements of lumbar spine bone mineral density ( L2–4 BMD ) and femoral neck BMD were made using dual-energy X-ray absorptiometry .  The fracture groups were significantly older and had more years since menopause than the control groups . Logistic regression showed that measurements of UTV , STF and BUA discriminated between fracture and non-fracture subjects for both the hip ( p<0.001 ) and spine ( p<0.05 ) . Femoral neck BMD discriminated both hip and vertebral fractures from controls ( p<0.001 and p<0.01 , respectively ) . Spinal BMD discriminated between subjects with vertebral fractures and those without ( p<0.01 ) , but not hip fractures ( p=0.64 ) . For hip fracture , areas under receiver-operating characteristic ( ROC ) curves were 0.85 for UTV , 0.83 for STF , 0.79 for BUA , 0.78 for femoral neck BMD and 0.53 for spinal BMD . For vertebral fracture , areas under the ROC curve were 0.68 for UTV , 0.70 for STF , 0.66 for BUA , 0.66 for femoral neck BMD and 0.67 for spinal BMD . To determine whether calcaneal ultrasonic measurements discriminated , independently of BMD , fracture from control groups , UTV , BUA and STF were adjusted for BMD , age and years since menopause using multiple regression analysis and the residuals from the regressions were incorporated into a logistic regression analysis . Adjusted ultrasonic measurements discriminated hip fracture from control groups ( p<0.005 for UTV;p<0.05 for BUA;p<0.01 for STF ) but not vertebral fracture ( p=0.37 for UTV;p=0.53 for BUA;p=0.25 for STF ) . These results show that , when ultrasonic measurements were adjusted for BMD and age , they still discriminated between hip fracture and control groups . This finding supports the hypothesis that ultrasonic measurements contain information about bone strength not contained in bone density measurements that may be useful in predicting hip fractures . Therefore , calcaneal ultrasound measurements may provide a safe , low-cost addition to bone densitometry We investigated the usefulness of bone density measurements from multiple skeletal sites and calcaneus ultrasound for evaluating the probability of vertebral deformation .  Bone mineral density ( BMD ) was measured at the second metacarpal and middle phalanges using radiographic absorptiometry of h and radiographs , and at the lumbar spine using dual-energy x-ray absorptiometry . Distal radius and proximal radius were measured using single-energy x-ray absorptiometry ( SXA ) , expressed as bone mineral content ( BMC , grams per centimeter ) , and as BMD ( grams per square centimeter ) . The calcaneus was measured using both SXA ( BMD ) and broadb and ultrasound attenuation ( BUA ) . Among the women in this study ( mean age 74 , SD = 5 ) , 84 women developed new vertebral deformations ( 57 cases with one and 27 cases with two or more deformations ) , which were identified on serial radiographs during an average of 9 years prior to the measurements of bone density . Logistic regression analysis was used to calculate odds ratios for risk of deformation corresponding to a 1-SD difference in density or ultrasound , adjusted for age . All bone measurements were significantly associated with vertebral deformation , with odds ratios ( 95 % confidence intervals ) ranging from 1.40 ( 1.10 , 1.78 ) for proximal radius BMD to 1.88 ( 1.45 , 2.44 ) for calcaneus BMD measurements . Measurements of calcaneal BUA , calcaneal BMD , and h and BMD generally remained significant when included simultaneously with another measurement in the same model , suggesting that spine or radius BMD may not provide much additional information about risk of deformation . It appears that all of the measurements of bone density and ultrasound provide useful information regarding the probability of deformation . These findings await confirmation in a prospect i ve study BACKGROUND Previous studies have shown that alendronate can increase bone mineral density ( BMD ) and prevent radiographically defined ( morph 
    Output:
    
Broadb and ultrasound attenuation measures the frequency dependence of attenuation of the ultrasound signal that occurs as energy is removed from the wave , primarily by absorption and scattering in the bone and soft tissue ( 21 ) .
Speed of sound and velocity of sound measure the distance the ultrasound signal travels per unit of time ( 22 ) .
Quantitative ultrasound index and stiffness are composite parameters derived from broadb and ultrasound attenuation and speed of sound or velocity of sound ( 21 , 22 ) .
Ultrasound parameter values are typically lower in osteoporotic bone than in healthy bone ( 22 ) .
Some evidence suggests that women selected for osteoporosis therapy on the basis of fracture risk factors rather than low DXA BMD may not benefit similarly from treatment ( 7 ) .
In the absence of direct evidence of treatment efficacy for patients identified by quantitative ultrasound as having high risk for fracture , the clinical utility of this test for improving osteoporosis outcomes lies with its degree of correlation with DXA results ( 40 ) .