Reconciling quantitative ultrasound of the calcaneus with X-ray-based measurements of the central skeleton

Clinical Conformity Between Heel Ultrasound and Densitometry in Postmenopausal Women: A Systematic Review

OBJECTIVES

To assess the conformity between heel ultrasound and densitometry, and the clinical application of densitometry T-score "gold standard" in quantitative ultrasound as a method of osteoporosis diagnosis in postmenopausal women.

METHODS

The study is a systematic review of studies published in the last 17 years in PubMed, NLM Gateway, Medline, Embase, and Cochrane Library. Calcaneal quantitative ultrasound sensitivity and specificity were analyzed with regard to densitometry measurements in postmenopausal women. In addition, we summarized the values of ultrasound T-scores, for which their accuracy in osteoporosis diagnosis is the highest.

RESULTS

The inclusion criteria met 15 research studies conducted on postmenopausal women. In 11 of them, the authors concluded that clinical conformity between heel ultrasound and densitometry is good. The recommended quantitative ultrasound T-score for osteoporosis diagnosis ranged between -1 and -3.65.

CONCLUSIONS

Heel ultrasound should be considered to be as accurate as densitometry in diagnosing osteoporosis. Nevertheless, it needs to have separate T-score ranges determined, because those used in densitometry are not adequate.

Diagnostic devices for osteoporosis in the general population: A systematic review

INTRODUCTION

A diagnostic gap exists in the current dual photon X-ray absorptiometry (DXA) based diagnostic approach to osteoporosis. Other diagnostic devices have been developed, but no comprehensive review concerning the applicability of these diagnostic devices for population-based screening have been performed.

MATERIAL AND METHODS

A systematic review of Embase, Medline and the Cochrane Central Register for Controlled Trials was performed for population-based studies that focused on technical methods that could either indicate bone mineral density (BMD) by DXA, substitute for DXA in prediction of fracture risk, or that could have an incremental value in fracture prediction in addition to DXA. Quality of included studies was rated by QUADAS 2.

RESULTS

Many other technical devices have been tested in a population-based setting. Five studies aiming to indicate BMD and 17 studies aiming to predict fractures were found. Overall, the latter studies had higher methodological quality. The highest number of studies was found for quantitative ultrasound (QUS). The ability to indicate BMD or predict fractures was moderate to minor for all examined devices, using reported area under the curve (AUC) of Receiver Operating Characteristic curves values as standard.

CONCLUSIONS

Of the methods assessed, only QUS appears capable of perhaps replacing DXA as standalone examination in the future whilst radiographic absorptiometry could provide important information in areas with scarcity of DXA. QUS may be of added value even after DXA has been performed. Evaluation of proposed cutoff-values from population-based studies in separate population-based cohorts is still lacking for most examination devices.

Is calcaneal quantitative ultrasound useful as a prescreen stratification tool for osteoporosis?

Calcaneal quantitative ultrasound (QUS) is attractive as a prescreening tool for osteoporosis, alternative to dual-energy X-ray absorptiometry. We investigated the literature of the usability of calcaneal QUS. We found large heterogeneity between studies and uncertainty about cutoff, device, and measured variable. Despite osteoporosis-related fractures being a major health issue, osteoporosis remains underdiagnosed. Dual-energy X-ray absorptiometry (DXA) of the hip or spine is currently the preferred method for diagnosis of osteoporosis, but the method is limited by low accessibility. QUS is a method for assessing bone alternative to DXA. The aim of this systematic review was to explore the usability of QUS as a prescreen stratification tool for assessment of osteoporosis. Studies that evaluated calcaneal QUS with DXA of the hip or spine as the gold standard was included. We extracted data from included studies to calculate number of DXAs saved and misclassification rates at cutoffs equal to high sensitivity and/or specificity. The number of DXAs saved and percentage of persons misclassified were measures of usability. We included 31 studies. Studies were heterogeneous regarding study characteristics. Analyses showed a wide spectrum of percentage of DXAs saved (2.7-68.8%) and misclassification rates (0-12.4%) depending on prescreen strategy and study characteristics, device, measured variable, and cutoff. Calcaneal QUS is potentially useful as a prescreen tool for assessment of osteoporosis. However, there is no consensus of device, variable, and cutoff. Overall, there is no sufficient evidence to recommend a specific cutoff for calcaneal QUS that provides a certainty level high enough to rule in or out osteoporosis. Calcaneal QUS in a prescreen or stratification algorithm must be based on device-specific cutoffs that are validated in the populations for which they are intended to be used.

Quantitative ultrasound variables of the heel in Finnish men aged 18-20 yr: predictors, relationship to bone mineral content, and changes during military service

INTRODUCTION

Determinants of BUA and SOS and their changes during military service-associated physical training were studied in 196 army recruits and 50 control men, aged 18-20 years.

METHODS

Heel ultrasound measurement, DXA, muscle strength test, Cooper's running test and genetic analyses were performed. Lifestyle factors were recorded. Sex steroids and bone turnover markers were determined. Heel ultrasound was repeated after six months.

RESULTS

Exercise was the most significant determinant of both BUA (p<0.0001) and SOS (p<0.0001). There were 10% and 1.3% differences in BUA (p=0.006) and SOS (p=0.0001), respectively, between men belonging to the lowest and highest quartiles of exercise index. Weight associated with BUA (p=0.005) and height with SOS (p=0.03). BUA and SOS correlated with BMC and BMD (p<0.0001) but explained only up to 21% of their variance. Over six months SOS increased more in recruits than in control men (p=0.0043), the increase being higher, the lower muscle strength at baseline (r =-0.27, p=0.0028).

CONCLUSION

Exercise is the most important determinant of ultrasonographic variables in men, aged 18-20 years. Physical loading during military training increases SOS.

Quantitative ultrasound of the calcaneus in long-term liver or cardiac transplantation patients

Bone loss is one of the most common complications after solid-organ transplantation, but it is frequently under-diagnosed. Our purpose was to evaluate quantitative ultrasound of calcaneus (QUS) in comparison with dual-energy X-ray absorptiometry (DXA) to identify transplant recipients with osteoporosis. We have cross-sectionally evaluated 140 transplant recipients (85 liver and 55 cardiac transplantations; mean age: 53.6 years, time since transplantation: 67.9 months). Devices used were Hologic 4500 QDR for DXA measurements and Sahara Clinical Sonometer (Hologic Inc, Bedford, MA) for calcaneal QUS. Quantitative ultrasound index (QUI) was calculated from speed of sound (m/s) and broadband ultrasonic attenuation (dB/MHz). QUI T-score and bone mineral density (BMD) T-score (spine and hip) were obtained from Spanish normative data. According to World Health Organization criteria, defined either at lumbar spine or femoral neck, 61% of the females had osteopenia and 32% had osteoporosis, whereas 52% of the males had osteopenia and 11% had osteoporosis. Calcaneal QUS parameters (speed of sound, broadband ultrasonic attenuation, and QUI) were positively correlated with lumbar and femoral BMD (p<0.001). In receiver operator characteristic analysis, a T-score QUI<or=-1.4 standard deviation (SD) had 68% sensitivity and 72% specificity for osteoporosis diagnosis by DXA criteria. However, to obtain maximal sensitivity (5% of false-negative), QUI T-score cutoff should be -0.6 SD, but specificity drops to 42%. In conclusion, a positive correlation exists between lumbar and femoral BMD and QUS parameters in long-term liver or cardiac transplant recipients. QUS could be recommended for screening of osteoporosis in long-term transplanted patients.

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.

Comparison of the Achilles Express ultrasonometer with central dual-energy X-ray absorptiometry

BACKGROUND

Quantitative ultrasound (QUS) devices provide portable, easy-to-operate, low-cost options for point-of-care screening of bone mineral density (BMD). Community pharmacists should be aware of the precision, sensitivity, and specificity of these devices prior to their purchase.

OBJECTIVE

To determine the precision, sensitivity, and specificity of the Achilles Express ultrasonometer compared with central dual-energy X-ray absorptiometry (cDXA) as well as its utility as a bone density screening device in the community pharmacy setting.

METHODS

A prospective study in a community pharmacy and outpatient ambulatory clinic was conducted with 2 groups of white women. Group 1 participants were 25-35 years of age (young, healthy), and those in Group 2 were 45 years of age or older (postmenopausal). BMD assessments of the spine and the nondominant wrist and hip were performed using cDXA. Assessments of the heel were performed using the Achilles Express, a QUS device. The main outcome measures were correlation of t-scores between cDXA and QUS measurements using the Pearson correlation test.

RESULTS

Twenty-two (30 +/- 4 years of age) and 31 (55 +/- 17 years of age) women were enrolled into Groups 1 and 2, respectively. Significant correlations between QUS and hip and spine cDXA t-scores were found in both groups. Correlation coefficients for QUS versus hip cDXA were 0.51 (95% CI 0.11 to 0.77) and 0.70 (95% CI 0.46 to 0.85) in Groups 1 and 2, respectively. Correlation coefficients for the QUS versus spine cDXA were 0.64 (95% CI 0.31 to 0.84) and 0.60 (95% CI 0.31 to 0.79) in Groups 1 and 2, respectively. The QUS device has a sensitivity level of 88% and specificity of 71% to detect a hip cDXA t-score of less than-1.

CONCLUSIONS

The Achilles Express ultrasonometer is a reasonable screening tool to detect low BMD in postmenopausal women.

Osteoporosis Screening and Education in Community Pharmacies Using a Team Approach

STUDY OBJECTIVES

To develop a model for osteoporosis screening and education in community pharmacies using a team approach, compare bone mineral density T-scores between quantitative ultrasound (QUS) and dual-energy x-ray absorptiometry (DXA), and determine patient satisfaction with this pharmacist-provided osteoporosis screening and education program.

DESIGN

Prospective, cross-sectional study.

SETTING

Community pharmacies and outpatient family medicine, internal medicine, and obstetrics and gynecology clinics in Amarillo, Texas.

PATIENTS

Women aged 55 years or older with no previous diagnosis of osteoporosis or osteopenia who had at least one additional risk factor for osteoporosis and had not been screened in the previous 3 years.

INTERVENTION

Patients were referred from family medicine, internal medicine, and obstetrics and gynecology clinics to a community pharmacy. Osteoporosis screening using heel QUS and education regarding disease prevention and treatment were provided by pharmacists. Screening results, recommendations for confirmatory DXA, and potential treatments options were provided to the referring physicians.

MEASUREMENTS AND MAIN RESULTS

A total of 100 patients (mean age 66.2+/-7.9 yrs) were enrolled in the study; three were subsequently excluded. Of the 97 study patients who were screened using QUS, 45 (46%) patients were at moderate risk (T-score<-1 to>-2.5) and nine (9%) were at high risk (T-score<or=-2.5). Of 54 patients recommended for DXA referral, 20 (37%) completed the scan. All 20 were diagnosed with either osteopenia (9 patients [45%]) or osteoporosis (11 patients [55%]). Correlation was moderate between T-scores obtained by QUS and DXA of lumbar vertebrae 1-4 (r=0.45, p=0.026). Counseling regarding risk factors, screening results, smoking cessation, calcium intake, exercise, and caffeine intake was perceived by patients as valuable or highly valuable (medians for all items ranged from 4-5 on a 5-point Likert scale). Of 84 patients assessed (13 were lost to follow-up), 81 (96%) said they would recommend this service to others.

CONCLUSION

Osteoporosis screening and education in community pharmacies are effective in detecting undiagnosed disease and are perceived by patients as highly useful.

Osteoporosis: Point-of-Care Testing

OBJECTIVE

To review the literature concerning the utility of point-of-care (POC) testing devices for the diagnosis and management of osteoporosis.

DATA SOURCES

Articles were identified from a MEDLINE search (1993–June 2003). Additional references were obtained from cross-referencing the bibliographies of selected articles.

STUDY SELECTION AND DATA EXTRACTION

After evaluation of clinical trials and select review articles, articles comparing peripheral dual-energy absorptiometry (pDXA) or quantitative ultrasound (QUS) with central DXA (cDXA) measurements were emphasized in this analysis.

DATA SYNTHESIS

Sensitivity for detecting osteoporosis by QUS or pDXA varies widely (range 35–75%). Using adjusted T-score cutoffs increases sensitivity to 85–95%, at the price of reducing device specificity to 23–49%. Many states require a radiology technician to perform pDXA tests.

CONCLUSIONS

POC testing with peripheral devices should only be considered in areas with limited access to cDXA or for women who initially refuse cDXA testing. T scores of −1.0 or less with POC testing typically require further evaluation via cDXA. Many states require pDXAs to be performed by certified radiology technologists, making QUS use more feasible for pharmacists. POC testing should not be used for assessing response to osteoporosis therapy.

Quantitative ultrasound of the calcaneus as a screening tool to detect osteoporosis: different reference ranges for caucasian women, african american women, and caucasian men

The interpretation of results measured by quantitative ultrasound (QUS) of the heel depends on the population studied. We measured estimated bone mineral density (BMD) of the heel using the Hologic Sahara sonometer. People were studied at county fairs, health fairs, and churches. Subjects were not on treatments that would affect bone density, other than calcium supplementation. This included 823 Caucasian women, 131 African American women, and 301 Caucasian men. In contrast to women, for Caucasian men the squared term for age was not significant, and a straight line of decline was the best fit for estimated BMD. African American women had a standard deviation larger than that reported by Hologic for Caucasian women. We compared a history of self-reported fractures with a subject's estimated BMD. An estimated BMD of 0.57 gm/cm2 included 75% of all fractures. This cutoff point was associated with increased fracture prevalence in subjects over age 50, relative risk of 1.4. This result corresponds to the Hologic data T-score of -0.2. When used as a screening tool for osteoporosis fracture risk, an estimated BMD of 0.57 gm/cm2 seems reasonable in those subjects over age 50.

Discriminatory ability of quantitative ultrasound measurements is similar to dual-energy X-ray absorptiometry in a Brazilian women population with osteoporotic fracture

The discriminating ability and relevance of clinical risk factors, quantitative ultrasound (QUS) variables, X-ray-based bone mineral density (BMD) and hip axis length (HAL) measurements to evaluate the risk of osteoporotic fracture in elderly Brazilian women were examined in this study. QUS at the calcaneus (Achilles +, Lunar), HAL and BMD measurements (DPX-L, Lunar) at several anatomical sites were performed in 275 postmenopausal Caucasian women. Patients with suspected secondary osteoporosis were excluded. One hundred twenty-two (44.4%) women had had previous osteoporotic fracture. All of the subjects were over 50 years old (range 53-93) and answered a questionnaire that included details concerning aspects of lifestyle, diet, hormonal factors and drug use. Lateral thoracic and lumbar radiographs were taken and an independent radiologist reviewed the X-rays for the presence of vertebral fractures. After adjustments for age, the most relevant risk factors to discriminate patients with osteoporotic fracture from normal non-fracture controls were Stiffness index (OR 2.8 per standard deviation; 95% confidence interval 2.3, 8.7), familial history of hip fracture (OR 2.6 per standard deviation; 95% confidence interval 2.2, 5.4), femoral neck BMD (OR 2.3 per standard deviation; 95% confidence interval 1.9, 4.2), age (OR 2.1 per standard deviation; 95% confidence interval 1.6, 2.8) and weight (OR 1.9 per standard deviation; 95% confidence interval 1.5, 2.6). HAL measurements did not associate significantly with the risk of hip fracture in this population. The ability of QUS measurements discriminate between patients with fractures from those without was similar to, if not better, than X-ray-based BMD measurements. However, a combination of QUS and BMD measurements did not significantly improve fracture discrimination compared with either technique alone. Association of clinical risk factors with QUS or BMD measurements seems, on the other hand, to increase the sensibility to identify patients at risk of osteoporotic fractures.

Osteoporosis in pulmonary clinic patients: does point-of-care screening predict central dual-energy X-ray absorptiometry?

STUDY OBJECTIVES

Patients in a pulmonary clinic have disorders that predispose them to osteoporosis and may use glucocorticoid therapy, which has been associated with low bone mineral density (BMD) and increased fracture risk. Ideally, all patients at risk for osteoporosis would be screened using the best test available, which is central BMD by dual-energy x-ray absorptiometry (DXA). We proposed to stratify the risk for osteoporosis by the use of a simple questionnaire and point-of-care heel ultrasound BMD measurements.

DESIGN

Cross-sectional screening study.

SETTING

Pulmonary clinic in a single Veterans Affairs Medical Center.

PATIENTS

Approximately 200 male and female patients who had not had previous BMD testing were eligible for the study, and 107 gave consent.

INTERVENTIONS

One hundred seven men (white, 71 men; black, 35 men; and Asian, 1 man) underwent heel BMD testing and filled out a questionnaire. Ninety-eight men underwent a central DXA.

RESULTS

Of 98 subjects, 24.5% had a spine, total hip, or femoral neck (FN) T-score of <or= -2.5, which is the generally accepted definition of osteoporosis diagnosed using DXA, and 44.9% had a T-score of <or= -2.0. The best-fit models for predicting FN or total hip BMD included body weight, heel BMD, corticosteroid use for >or= 7 days, and race, which accounted for 52 to 57% of the variance. When a heel ultrasound T-score of -1.0 was tested to predict a central DXA T-score of -2.0, the sensitivity was 61% and the specificity 64%. Adding the questionnaire score and body mass index (BMI) to the heel T-score improved sensitivity but not specificity. Moreover, BMI and age predicted central BMD with similar sensitivity and specificity. Importantly, of 24 patients with a central DXA T-score of <or= -2.5, only 14 were identified by a heel T-score of <or= -1.0.

CONCLUSIONS

Although the findings from a heel ultrasound plus the answers to a questionnaire were reasonably good indicators for predicting the presence of low BMD, little predictability was gained over the use of BMI and age. In a group of pulmonary clinic patients, the prevalence of osteoporosis was clinically significant, and central DXA testing was the preferable technique for identifying patients who were at risk for fracture.

Performance of quantitative ultrasound in the discrimination of prevalent osteoporotic fractures in a bone metabolic unit

There is a growing interest in ultrasound evaluation of bone status as an alternative to the measurement with dual X-ray absorptiometry (DXA), due to its low cost, portability, and nonionizing radiation. The aim of our study was to investigate the relation among DXA, QUS, clinical, anthropometric, and lifestyle factors, and to determine QUS cutoff values in order to discriminate fractures in patients referred to the Bone Metabolic Unit at an Endocrinology Service. We studied 300 patients (281 females and 19 males; age 58 +/- 11 years) referred for evaluation of osteoporosis. In all cases we determined basic anthropometric parameters, a clinical history including previous osteoporotic fractures and risk factors for osteoporosis, and QUS parameters in calcaneus (Hologic Sahara), and BMD in lumbar spine (LS) and femoral neck (FN), by DXA (Hologic QDR 1000). Using the WHO densitometric criteria, 37, 46.7, and 16.3% of our population were osteoporotic, osteopenic, and normal, respectively. A QUI T-score </=-1.5 SD provided a sensitivity of 68.9% and a specificity of 64.7% for osteoporotic fracture discrimination and a sensitivity of 64.9% and a specificity of 74.1% for osteoporosis defined by WHO criteria using DXA. In the logistic regression, the presence of family history of fragility fractures (OR: 3.03; CI 95%: 1.3-7.03), a DXA T-score </=-2.5 (OR: 3.58; CI 95%: 1.66-7.73), and a QUI T-score </=-1.5 (OR: 2.56; CI 95%: 1.15-5.69) were independently associated with prevalent osteoporotic fractures. In conclusion, calcaneus ultrasound appears as a useful technique for the routine clinical practice, as its performance is similar to DXA for the discrimination of subjects with osteoporotic fracture.

[Non-invasive method for measuring bone mineral density]

Measurement of bone mineral density (BMD) using dual energy X-ray absorptiometry is the basis of the definition of osteoporosis. Accuracy, precision and sensitivity of the method are good enough for clinical use. Prospective studies have shown that there is a gradient of risk between the decrease in BMD, related to age and hormonal insufficiency, and the increase in the incidence of fracture. Thus, therapeutic decision is based on both BMD and clinical risk factors that contribute to fracture risk.

Evaluation of calcaneal quantitative ultrasound in a primary care setting as a screening tool for osteoporosis in postmenopausal women

Screening of osteoporosis by quantitative ultrasound (QUS) has become widely available in Europe, but no clear strategies for its clinical use have been established. The aim of this study was to validate the use of QUS in a cross-sectional study carried out in three primary care centers. Measurements of calcaneal QUS and bone mineral density (BMD) at proximal femur were obtained by dual-energy X-ray absorptiometry (DXA). Osteoporosis was diagnosed by DXA T-score <or= -2.5 at the femoral neck. Sensitivity, specificity, kappa index, and receives operator characteristics (ROC) curve QUS values were calculated with respect to the standard reference. Both positive and negative likelihood ratios (LR) were used to calculate the optimum cut-off levels. Two hundred and sixty-seven women aged 65 or older were included. Fifty-five percent had osteoporotic femoral neck BMD values (T-score <or= -2.5). The same threshold for QUS yielded a lower prevalence of osteoporosis (10%). Women with BMD diagnosis of osteoporosis were older and showed lower age-adjusted values for all QUS parameters (p < 0.001). Area under the curve (AUC) ranged from 0.662-0.678 for the different QUS parameters; correlation and concordance of all parameters with femoral neck BMD were statistically significant (p < 0.001). Cut-off values calculated from the AUC yielded 61.1% sensitivity and 65.3% specificity for the best QUS parameter (i.e., Estimated Heel T-score <or= -1.55). Estimated Heel T-score values of +0.05 or above ruled out osteoporosis (LR 0.18), whereas those -2.50 or below supported the diagnosis (LR 5.98). The application of these cutoff points allowed classification of 22.1% of cases. In conclusion, in postmenopausal women, QUS screening conclusively confirms or rules out osteoporosis in approximately one-fifth of cases, thereby avoiding the need for a DXA measurement.

Prevalence of low bone density in institutionalized men with developmental disabilities

This study investigates the prevalence and degree of low bone mineral density (BMD) in a group of 108 institutionalized men with developmental disabilities. Speed of sound (SOS) and broadband attenuation (BUA) of the calcaneus were measured to determine a quantitative ultrasound index (QUI). Comparison was made to the values for this index in a reference population of age-matched and young adult controls. Thirty-four percent of the study participants had QUI values more than 2 standard deviations (SDs) below those of age-matched controls. Fifty-one percent of this population showed QUI values more than 2 SDs below those of the young adult reference group, suggesting a high prevalence of significantly decreased BMD.

Biochemical and ultrasound tests for early diagnosis of active neuro-osteoarthropathy (NOA) of the diabetic foot

OBJECTIVES

To test the effectiveness of a combined approach to an early diagnosis of neuro-osteoarthropathy (NOA) of the diabetic foot, we studied a group of outpatients with active NOA, presenting for the first time to our Diabetic Foot Clinic in 1998, by means of an integrated approach designed to assess bone turnover.

PATIENTS AND METHODS

Fifteen consecutive diabetic patients (five Type 1 and ten Type 2 diabetic individuals, age 61.9+/-12.2 years, diabetes duration 18.7+/-8.9 years, HbA(1c) 8.4+/-1.5%) with active NOA (Group 1) were compared to nine diabetic patients with chronic stable NOA (Group 2), 14 neuropathic diabetic patients without NOA (Group 3), 13 non-neuropathic diabetic patients (Group 4) and 15 healthy controls (Group 5). Determination of serum carboxy-terminal collagen telopeptide (ICTP), bone alkaline phosphatase isoenzyme (B-ALP), osteocalcin (BGP) concentrations, as well as urinary excretion of deoxypyridinoline (DPD) were obtained in all individuals for assessment of bone reabsorption and new bone formation. Moreover in all individuals quantitative ultrasound (QUS) of the calcaneal bone was performed and mass density of lumbar spine and femur bone was determined by dual-energy X-ray absorptiometry (DEXA).

RESULTS

QUS was significantly lower in the active NOA patients as compared with other groups (P<0.01), while ICTP was higher in both NOA groups (P<0.01). Urinary DPD was higher in the neuropathic non-NOA group (P<0.01) than the other groups, and osteocalcin was higher in healthy controls compared to diabetic patients without NOA. QUS and ICTP were inversely correlated (r=0.44, P=0.000). QUS in the active NOA group was significantly (P<0.01) lower in the affected compared to the unaffected foot.

CONCLUSION

Our results indicate a possible role for an integrated approach to the diagnosis and monitoring of NOA involving the diabetic foot. DPD may identify patients at-risk for NOA, ICTP could be tested as a marker for NOA in asymptomatic cases. Finally, QUS of the calcaneal bone may be useful in discriminating active versus quiescent phases.

The use of ultrasound in the assessment of bone status

The assessment of skeletal status has wide clinical applications, especially in the management of osteoporosis. Osteoporosis, once thought of as an unpreventable and untreatable aging process, has revealed many of its secrets over the last decade, and the advent of successful drug therapy has changed our perception of the disease. Non-invasive techniques play a fundamental role in the diagnosis of osteoporosis and in the assessment of the efficacy of drug treatments. The primary technique used in osteoporosis is dual X-ray absorptiometry (DXA), that has been established as a reliable means of measuring bone density. Quantitative ultrasound (QUS), because of the relative portability of the equipment, ease of use, lack of ionizing radiation and low cost, has great potential for widespread use. Five devices for QUS assessment have recently been approved by the Food and Drug Administration and many more applications are in progress. QUS is a relatively new technology, at least in its application to bone fragility. Nevertheless, QUS has demonstrated that it is able to detect bone fragility as well as DXA. However, diagnosis of osteoporosis by QUS remains contentious, but the problems are due more to the limitations of the present T-scores rather than to the technique. A better option for QUS would be to report results in terms of remaining lifetime fracture risk, keeping in mind that a risk estimate needs not only the QUS or DXA measurement, but also the specific data, such as age, weight, gender, hormonal status and fracture history of the patient.

Physician treatment of osteoporosis in response to heel ultrasound bone mineral density reports

Optimal information that should be included in ultrasound (US) heel bone mineral density (BMD) reports is not known. If additional information about further evaluation of patients with low heel BMD were included in reports, would responses for treatment improve? We screened people at health fairs using the Sahara heel US machine. For those with a T-score of </= 1.0, letters were sent to their primary care physician notifying them of the result. Physicians were randomly assigned to (1) a standard letter, which recommended central bone density screening (dual X-ray absorptiometry [DXA]) and treatment if the BMD was low; or (2) an extended letter, which also outlined treatment strategies based on recommended subsequent central DXA scan results for a T-score of < 1.50 and also if < 2.00. The extended letter only increased the frequency of DXA testing from 30.1 to 37.2% (not a significant increase). Of 88 people with heel BMD </= 1.00 and not previously on any treatment, 25 of 45 (56%) were treated (calcium, estrogens, bisphosphonates, or calcitonin or a combination) after physicians received a standard letter and 30 of 43 (70%) after an extended letter (one-sided p = 0.084). Of people with T </= 1.9, and initially taking nothing more than calcium, 5 of 36 (13.9%) received additional treatment after physicians received a standard letter vs 9 of 41 (22.0%) after an extended letter (one-sided p = 0.180). For those with T </= 1.0 because of the screen 25 of 197 (12.7%) received additional treatment. One hundred forty-six of 194 (75%) individuals and received treatment with calcium or other medications, and 74 of 173 (43%) of individuals before screening and 141 of 195 (72%) after physicians received letters took calcium. Physicians regarded calcium alone as adequate treatment in many cases. There was no marked increase in treatment when additional information was provided to physicians regarding evaluation and treatment for low US heel BMD results.

Bone density in competitive figure skaters

OBJECTIVES

To compare the bone mineral density (BMD) of competitive female teenage figure skaters with a history of fracture with the BMD of skaters without fracture and to compare each group to age-matched, nonathletic controls.

DESIGN

Retrospective age-matched cohort.

SETTING

Tertiary care medical center and 3 local skating clubs.

PARTICIPANTS

Thirty-six adolescent female competitive skaters (10 with fracture, 26 without fracture) to 22 age-matched controls.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

BMD was estimated by quantitative ultrasound.

RESULTS

Skaters who had suffered stress fractures had BMD values comparable with those of healthy nonathletic controls. However, skaters who had not suffered stress fractures had calcaneal BMD values 15% to 24% greater than either the controls or skaters with fractures. Among the skaters without fracture, there was a 14% to 19% higher calcaneal BMD in skaters who executed triple jumps relative to skaters who performed only double jumps. Furthermore, there was 7% to 11% greater BMD in the landing foot of the skaters relative to the takeoff foot.

CONCLUSIONS

Stress fractures in adolescent skaters are not caused by low bone mass but may result from excessive forces placed on a normal skeleton. Our findings also support the hypothesis that higher peak forces are applied to the landing foot relative to the takeoff foot.

Comparison of heel ultrasound and finger DXA to central DXA in the detection of osteoporosis. Implications for patient management

The goal of the study was to investigate the potential discordance in patient management when a clinician assumes that a peripheral device is a diagnostic surrogate for central DXA in the detection and treatment of osteoporosis. Over a period of 2 mo, asymptomatic women seeking conventional central DXA evaluation for osteoporosis at a diagnostic imaging center were also evaluated with heel ultrasound and finger DXA peripheral imaging devices. T-Scores of -2.5 or less in screening examinations were used to evaluate the discordance between the two peripheral devices and central DXA in the identification of patients with osteoporosis. Higher T-score cutoffs (>-2.5) were also evaluated. Using central DXA as the standard for comparison, the sensitivity of heel ultrasound for screening cases was 0.34 and specificity was 0.92. For finger DXA, sensitivity was 0.23 and specificity was 0.92. Overall discordance between the peripheral devices and central DXA was 21% (heel) and 23% (finger). Heel ultrasound identified 7 out of every 22 osteoporotic patients diagnosed with central DXA. Finger DXA identified 5 out of every 22 osteoporotic patients. Using lower T-scores for the peripheral devices increased sensitivity but markedly increased discordance with DXA. The peripheral devices we studied cannot be considered equivalent surrogates for central DXA in the screening of asymptomatic women for osteoporosis.

Utility of heel ultrasound bone density in men

In women, heel ultrasound (US) bone mineral density (BMD) has been shown to predict fracture risk, but the usefulness of this screening tool in men is not known. We measured the heel quantitative ultrasound index (QUI( in a convenience sample 185 of men (136 Caucasian, 1 Asian, and 48 African-American) with an average age of 63 yr (range of 25-85) undergoing BMD of the spine and hip by dual X-ray absorptiometry (DXA) to determine whether the heel measurement could predict central BMD. The average DXA T-score was -0.97, -1.20, and -1.61 for the spine, total hip, and femoral neck, respectively. The mean heel US BMD T-score (using the only available T-score, which was defined for Caucasian postmenopausal women) was -0.92. There were significant correlations among the various DXA measurements and the heel US BMD T-score (r = 0.373-0.483, p < 0.001). We defined arbitrarily osteopenia as a spine, total hip, or femoral neck T-score by DXA of < -1.5. We also made two different arbitrary definitions of osteoporosis by DXA: < -2.0 and < -2.5. Using these numbers as disease definitions, we determined the specificity, sensitivity, as well as positive and negative predictive values of using the heel US T-score to predict osteopenia or osteoporosis. Using various cutoffs for the heel T-score, we found that increasing the cutoff toward 0 increased the sensitivity but lowered the specificity. No cutoff was found that provided both good sensitivity and specificity. By analyzing the men by ethnic and age groups, we found that the best set of receiver operating characteristic (ROC) curves was derived from data using heel US to predict osteopenia and osteoporosis in men younger than age 65, although the areas under the ROC curve were approx 0.8. In conclusion, despite a strong correlation between the heel QUI and the spine and hip BMD by DXA, no heel T-score could predict osteopenia or osteoporosis with satisfactory sensitivity and specificity. It is possible that the use of risk factor assessment plus heel QUI might have better predictive value, and further studies are needed to determine whether heel QUI or other US determination is an independent risk factor for fracture in men.