Quantitative Ultrasound (QUS) in the Management of Osteoporosis and Assessment of Fracture Risk

Computer-aided diagnosis systems for osteoporosis detection: a comprehensive survey

Computer-aided diagnosis (CAD) has revolutionized the field of medical diagnosis. They assist in improving the treatment potentials and intensify the survival frequency by early diagnosing the diseases in an efficient, timely, and cost-effective way. The automatic segmentation has led the radiologist to successfully segment the region of interest to improve the diagnosis of diseases from medical images which is not so efficiently possible by manual segmentation. The aim of this paper is to survey the vision-based CAD systems especially focusing on the segmentation techniques for the pathological bone disease known as osteoporosis. Osteoporosis is the state of the bones where the mineral density of bones decreases and they become porous, making the bones easily susceptible to fractures by small injury or a fall. The article covers the image acquisition techniques for acquiring the medical images for osteoporosis diagnosis. The article also discusses the advanced machine learning paradigms employed in segmentation for osteoporosis disease. Other image processing steps in osteoporosis like feature extraction and classification are also briefly described. Finally, the paper gives the future directions to improve the osteoporosis diagnosis and presents the proposed architecture. Graphical abstract.

Incidental bilateral calcaneal fractures following overground walking with a wearable robotic exoskeleton in a wheelchair user with a chronic spinal cord injury: is zero risk possible?

Many individuals with spinal cord injury (SCI) rely on wheelchairs as their primary mode of locomotion leading to reduced weight-bearing on the lower extremities, which contributes to severe bone loss and increased risk of fragility fractures. Engaging in a walking program may reverse this vicious cycle, as this promotes lower extremity weight-bearing and mobility, which may reduce bone loss and fragility fracture risk. However, fragility fracture risk associated with the use of wearable robotic exoskeletons (WREs) in individuals with SCI needs consideration. A 35-year-old man with chronic complete sensorimotor SCI (neurological level = T₆) and low initial bone mineral density enrolled in a 6- to 8-week WRE-assisted walking program after successfully completing an initial clinical screening process and two familiarization sessions with the WRE. However, after the first training session with the WRE, he developed bilateral localized ankle edema. Training was suspended, and a CT-scan revealed bilateral calcaneal fractures, which healed with conservative treatment over a 12-week period. Opportunities for improving clinical screening and WRE design are explored. The relevance of developing clinical practice guidelines for safe initiation and progression of intensity during WRE-assisted walking programs is highlighted. This case of bilateral calcaneal fractures illustrates that aiming for "zero risk" during WRE-assisted walking programs may not be realistic. Although WREs are a relatively new technology, current evidence confirms their potential to greatly improve health and quality of life in individuals with chronic SCI. Hence, ensuring their safe use remains a key priority.

Radiofrequency echographic multi spectrometry for the prediction of incident fragility fractures: A 5-year follow-up study

PURPOSE

To investigate the effectiveness of the T-score values provided by Radiofrequency Echographic Multi Spectrometry (REMS) in the identification of patients at risk for incident osteoporotic fractures.

METHODS

A population of Caucasian women (30-90 years), enrolled from 2013 to 2016, underwent dual X-ray absorptiometry (DXA) and REMS scans at axial sites. The incidence of fragility fractures was assessed during a follow-up period up to 5 years. Afterwards, patients with and without incident fractures were stratified in two age-matched groups with a 1: 2 proportion (Group F' and Group NF', respectively). The performance of REMS T-score in discriminating between the two groups was quantitatively assessed and compared with DXA.

RESULTS

1516 patients were enrolled and 1370 completed the follow-up (mean ± SD: 3.7 ± 0.8 years; range: 1.9-5.0 years). Fracture incidence was 14.0%. Age-matched groups included 175 fractured patients and 350 non-fractured ones, respectively (median age 70.2 [interquartile range: 61.0-73.3] and 67.3 [65.4-69.8] years, p-value ns). The groups resulted also balanced for height, weight and BMI (p-values ns). As expected, the differences in REMS T-score (for vertebral site, -2.9 [-3.6 to -1.9] in Group F', -2.2 [-2.9 to -1.2] in Group NF') and DXA T-score (-2.8 [-3.3 to -1.9] in Group F', -2.2 [-2.9 to -1.4] in Group NF') were statistically significant (p-value <0.001). Analogous results were obtained for femoral neck. Considering the T-score cut-off of -2.5, REMS identified Group F' patients with a sensitivity of 65.1% and specificity of 57.7% of (OR = 2.6, 95%CI: 1.77-3.76, p < 0.001), whereas DXA showed a sensitivity of 57.1% and a specificity of 56.3% (OR = 1.7, 95%CI: 1.20-2.51, p-value = 0.0032). For femoral neck, REMS sensitivity and specificity were 40.2% and 79.9%, respectively, with an OR of 2.81 (95%CI: 1.80-4.39, p < 0.001). DXA, instead, showed a sensitivity and specificity of 42.3% and 79.3%, respectively, with an OR of 2.68 (95%CI: 1.71-4.21, p < 0.001).

CONCLUSIONS

REMS T-score resulted an effective predictor for the risk of incident fragility fractures in a population-based sample of female subjects, representing a promising parameter to enhance osteoporosis diagnosis in the clinical routine.

The use of pulse-echo ultrasound in women with a recent non-vertebral fracture to identify those without osteoporosis and/or a subclinical vertebral fracture: a pilot study

A pilot study on the use of P-EU to identify patients without osteoporosis and/or a subclinical vertebral fracture after a recently sustained non-vertebral fracture (NVF).

INTRODUCTION

Screening with portable devices at emergency departments or plaster rooms could be of interest to limit referrals for dual X-ray absorptiometry (DXA) and vertebral fracture assessment (VFA). We calculated the number of negative tests for osteoporosis and/or subclinical vertebral fractures (VFs) using pulse-echo ultrasonometry (P-UE) at different thresholds.

PATIENTS AND METHODS

In this cross-sectional study, 209 consecutive women of 50-70 years with a recent non-vertebral fracture (NVF) were studied at the Fracture Liaison Service (FLS) of one hospital. All women received DXA/VFA and P-EU (Bindex®) assessments. Various P-EU thresholds (based on the density index (DI, g/cm²)) were analyzed to calculate the best balance between true negative (indeed no osteoporosis and/or subclinical VF) and false negative tests (osteoporosis and/or subclinical VF according to DXA/VFA).

RESULTS

Eighty-three women had osteoporosis (40%) and 17 women at least one VF (8%). Applying the manufacturer's recommended P-EU threshold (DI 0.844 g/cm²) being their proposed cut-off for not having hip osteoporosis resulted in 77 negative tests (37%, 31% true negative and 6% false negative tests). A DI of 0.896 g/cm² resulted in 40 negative tests (19.3%) (38 true negative (18.3%) and 2 false negative tests (1.0%)).

CONCLUSION

The application of P-EU enables the identification of a substantial proportion of women with recent non-vertebral fractures at the FLS who would not need a DXA/VFA referral because they had no osteoporosis and/or subclinical vertebral fractures. The most conservative P-EU threshold resulted in 18.3% true negative tests verified by DXA/VFA against 1% false negative test results.

The Performance of a Calcaneal Quantitative Ultrasound Device, CM-200, in Stratifying Osteoporosis Risk among Malaysian Population Aged 40 Years and Above

BACKGROUND

Calcaneal quantitative ultrasound (QUS) is widely used in osteoporosis screening, but the cut-off values for risk stratification remain unclear. This study validates the performance of a calcaneal QUS device (CM-200) using dual-energy X-ray absorptiometry (DXA) as the reference and establishes a new set of cut-off values for CM-200 in identifying subjects with osteoporosis.

METHODS

The bone health status of Malaysians aged ≥40 years was assessed using CM-200 and DXA. Sensitivity, specificity, area under the curve (AUC) and the optimal cut-off values for risk stratification of CM-200 were determined using receiver operating characteristic (ROC) curves and Youden's index (J). Results: From the data of 786 subjects, CM-200 (QUS T-score <-1) showed a sensitivity of 82.1% (95% CI: 77.9-85.7%), specificity of 51.5% (95% CI: 46.5-56.6%) and AUC of 0.668 (95% CI: 0.630-0.706) in identifying subjects with suboptimal bone health (DXA T-score <-1) (p < 0.001). At QUS T-score ≤-2.5, CM-200 was ineffective in identifying subjects with osteoporosis (DXA T-score ≤-2.5) (sensitivity 14.4% (95% CI: 8.1-23.0%); specificity 96.1% (95% CI: 94.4-97.4%); AUC 0.553 (95% CI: 0.488-0.617); p > 0.05). Modified cut-off values for the QUS T-score improved the performance of CM-200 in identifying subjects with osteopenia (sensitivity 67.7% (95% CI: 62.8-72.3%); specificity 72.8% (95% CI: 68.1-77.2%); J = 0.405; AUC 0.702 (95% CI: 0.666-0.739); p < 0.001) and osteoporosis (sensitivity 79.4% (95% CI: 70.0-86.9%); specificity 61.8% (95% CI: 58.1-65.5%); J = 0.412; AUC 0.706 (95% CI: 0.654-0.758); p < 0.001). Conclusion: The modified cut-off values significantly improved the performance of CM-200 in identifying individuals with osteoporosis. Since these values are device-specific, optimization is necessary for accurate detection of individuals at risk for osteoporosis using QUS.

The relationship between platelet count and bone mineral density: results from two independent population-based studies

In two population-based study of middle-aged and older people, we investigated if platelet count was associated with bone mineral density and determined whether the association remained over time. Highest platelet counts within the normal range are significantly associated with osteopenia and osteoporosis in middle-aged and elderly people.

PURPOSE

Recently, platelets were found to play a role in bone remodeling. However, data on the association between platelet count and osteoporosis are lacking. Our study aimed to investigate the association between platelet counts, osteopenia, and osteoporosis in middle-aged and elderly Koreans.

METHODS

We analyzed cross-sectional data from 5181 adults (postmenopausal women and men over 50 years of age) in the 2008-2011 Korea National Health and Nutrition Examination Survey (KNHANES) and longitudinal prospective data from 3312 adults over 50 years of age in the Korean Genome and Epidemiology Study (KoGES). Bone mineral density (BMD) was measured using dual-energy X-ray absorptiometry in the KNHANES and quantitative ultrasound in the KoGES. The platelet counts were categorized into quintiles within normal ranges (150-450 × 10³ μL). The associations between platelet counts, osteopenia, and osteoporosis were estimated using a multinomial logistic model.

RESULTS

BMD of the femur neck, total femur, and lumbar spine all decreased with increasing platelet counts. The cut-off points of the platelet counts to differentiate normal BMD from osteopenia and osteopenia from osteoporosis were 217 × 10³/μL and 269 × 10³/μL, respectively. The odds ratios (95% confidence intervals) in the highest platelet quartile were 1.39 (1.03-1.88) for osteopenia and 1.60 (1.07-2.37) for osteoporosis after adjusting for confounding factors. The distal radius T-score was significantly decreased in the highest platelet tertile group at a follow-up of 10 years.

CONCLUSION

Highest platelet counts within the normal range are significantly associated with osteopenia and osteoporosis in middle-aged and elderly people.

The Relationship Between Non-elite Sporting Activity and Calcaneal Bone Density in Adolescents and Young Adults: A Narrative Systematic Review

Introduction: Osteoporotic fractures represent a major public health burden. The risk of fragility fractures in late adulthood is strongly impacted by peak bone mass acquisition by the third decade. Weight-bearing sporting activity may be beneficial to peak bone mass accrual, but previous studies have focused on elite sporting activity and have used dual energy X-ray absorptiometry as a measure of bone density. The authors performed a narrative systematic review of individual sports (performed non-competitively or at local level) and calcaneal quantitative ultrasound (cQUS) bone measures in young people.

Methods: Multiple databases were systematically searched up until the 31st of March 2019. The authors included studies of participants' mean age (11–35 years), reporting any level of recreational sporting activity and cQUS measures as well as excluding elite/professional sporting physical activity. Studies (title and abstract) were screened independently by two reviewers, and a third reviewer resolved any discrepancies. STROBE guidelines were used to check the reporting of observational studies. The Newcastle–Ottawa Scale was used to assess the risk of bias of the studies included in the review. The systematic review was registered with the International Prospective Register of Systematic Reviews (PROSPERO).

Results: A search yielded 29,512 articles that considered relationships between bone density assessed by any technique and sporting activity. Duplicate and out of scope abstracts were removed. This left 424 papers that were screened by two reviewers; of these, six met the inclusion criteria, including assessment by cQUS. The authors identified papers where sports were considered, included soccer (football), swimming, cycling, gymnastics, dancing, badminton, basketball, fencing, wrestling, and judokas. Although study heterogeneity prohibited meta-analysis, all six included studies reported significant benefits of weight-bearing non-elite sports on cQUS outcomes.

Conclusion: Our study found beneficial effects of non-elite sports participation on cQUS in adolescence and young adulthood, although further work is now indicated.

Predictive value of quantitative ultrasound parameters in individuals with chronic kidney disease: A population-based analysis of CARTaGENE

BACKGROUND

The use of calcaneal quantitative ultrasound (QUS) to predict fractures has not been well studied in early CKD populations. We compared the association of QUS with incidental fractures and its predictive properties in non-CKD and CKD individuals.

METHODS

Analysis of a prospective population-based survey of 40- to 69-year-old individuals recruited between 2009 and 2010. QUS parameters (stiffness index [SI], speed of sound [SOS], broadband attenuation [BUA]) were measured at baseline. Renal function was measured using baseline creatinine and was classified into CKD stages (non-CKD, stage 2, stage 3). Fracture incidence at any site or at major osteoporotic fracture sites for up to 7 years of follow-up was identified in administrative databases using a validated algorithm. The association (age-adjusted hazard ratio per standard deviation decrease in Cox models), discrimination (c-statistic) and calibration (standardized incidence ratio [SIR]) of QUS parameters with fracture outcomes was computed in each CKD stratum.

RESULTS

We included 18,306 individuals (9,011 non-CKD; 8,595 CKD stage 2; 700 CKD stage 3). During a median follow-up of 70 months, we identified 782 fractures at any site and 326 major osteoporotic fractures. Although all QUS parameters (SI, SOS and BUA) were associated with any or major fracture incidence in non-CKD and CKD patients, the magnitude of these associations was lower for any fracture and for BUA. QUS parameters moderately discriminated incidental fractures across CKD strata but underestimated fracture incidence in CKD stage 3 even after adjustment for demographics and clinical risk factors. At a given QUS value, CKD stage 3 patients had higher fracture risk than non-CKD and CKD stage 2 patients.

CONCLUSIONS

QUS parameters are associated with fracture incidence in both non-CKD and CKD but underestimate fracture incidence in individuals with early CKD.

Structural and Metabolic Assessment of Bone

The assessment of bone structure and metabolism should focus on the bone strength. Many factors are involved, and although bone density is an important component, it is not the same as bone strength. Other aspects of bone quality include bone volume, micro-architecture, material composition, and ability to repair damage. This chapter briefly reviews some of the methods that can be used to assess both density and quality of bone. Non-invasive measurements of density or structure include dual X-ray absorptiometry (DXA), quantitative computed tomography, ultrasound, and magnetic resonance imaging. DXA is most widely used and has advantages of safety and accessibility, but there are limitations in the interpretation of the results, and in clinical practice positioning errors are frequently seen. Invasive methods are used primarily for research. Samples of bone can be used to measure structure by histology as well as micro-computed tomography and infra-red spectroscopy or backscattered electron microscopy. Force can be directly applied to bone samples to measure the bones strength. Impact microindentation is a new minimally invasive technique that measures bone hardness. Metabolic assessment includes blood and urine tests that reflect diseases that cause bone loss, particularly problems with mineral metabolism. Tetracycline-labelled bone biopsies are the standard for measuring bone formation. Non-invasive biochemical tests of bone formation and resorption can evaluate a patient's skeletal physiology.

Muscle-tendon weakness contributes to chronic fatigue syndrome in Gaucher's disease

Background

Chronic fatigue (CFg) is a prevalent symptom in Gaucher disease (GD) at diagnosis (79%) and remains in a quarter of patients after years of therapy. Bone abnormalities are present in over 70% and peripheral neuropathy in about 11% of the patients, which contributes to the disabling and debilitating complications. Our hypothesis is that other factors such as muscle-tendinous weakness could have influence in the development of CFg.

Methods

We have evaluated the fiber structure and elasticity of muscle-tendinous unit by strain-elastography (S-ELA) and analyzed their influence in the CFg. S-ELA study was performed in Achilles tendon in 25 type 1 and two type 3 GD patients, all of them with fatigue and were on enzymatic replacement therapy for mean 13 years; simultaneously, bone marrow burden by MRI and calcaneus ultrasound densitometry were evaluated. Blood cell counts, plasma biomarkers, GBA1 genotyping, and SF36 quality of life scale (QoL) were also performed. Statistical analysis: descriptive and comparative test.

Results

All patients showed a normal Achilles tendinous structure. Abnormal stiff grade 2–3 was found in 17/27 (62.9%); in 11/27 (40.7%) of patients, the alteration was bilateral. There were no correlations between the S-ELA results to other variables; nevertheless, a significant correlation between the degree of tendon hardness and the low score on the QoL scales (p = 0.0035) was found. The S-ELA is a sensitive painless, fast, and low cost method to detect muscle-tendinous subclinical dysfunction that could contribute to CFg in GD. The identification of subclinical tendon alteration would be a sign of alarm, focused on the risk of development of bone complications.

Conclusion

Intratendinous alteration in strain-elastography is an independent variable in GD patients with persistent fatigue.

Monitoring the Setting of Calcium Sulfate Bone-Graft Substitute Using Ultrasonic Backscattering

We report a method to monitor the setting process of bone-graft substitutes (calcium sulfate) using ultrasonic backscattering techniques. Analyzing the backscattered fields using a pulse-echo technique, we show that it is possible to dynamically describe the acoustic properties of the material which are linked to its setting state. Several experiments were performed to control the setting process of calcium sulfate using a 3.5-MHz transducer. The variation of the apparent integrated backscatter (AIB) with time during the setting process is analyzed and compared with measurements of the speed of sound (SOS) and temperature of the sample. The correlation of SOS and AIB allows us to clearly identify two different states of the samples, liquid and solid, in addition to the transition period. Results show that using backscattering analysis, the setting state of the material can be estimated with a threshold of 15 dB. This ultrasonic technique is indeed the first step to develop real-time monitoring systems for time-varying complex media as those present in bone regeneration for dental implantology applications.

Radiofrequency echographic multi-spectrometry for the in-vivo assessment of bone strength: state of the art-outcomes of an expert consensus meeting organized by the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO)

PURPOSE

The purpose of this paper was to review the available approaches for bone strength assessment, osteoporosis diagnosis and fracture risk prediction, and to provide insights into radiofrequency echographic multi spectrometry (REMS), a non-ionizing axial skeleton technique.

METHODS

A working group convened by the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis met to review the current image-based methods for bone strength assessment and fracture risk estimation, and to discuss the clinical perspectives of REMS.

RESULTS

Areal bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) is the consolidated indicator for osteoporosis diagnosis and fracture risk assessment. A more reliable fracture risk estimation would actually require an improved assessment of bone strength, integrating also bone quality information. Several different approaches have been proposed, including additional DXA-based parameters, quantitative computed tomography, and quantitative ultrasound. Although each of them showed a somewhat improved clinical performance, none satisfied all the requirements for a widespread routine employment, which was typically hindered by unclear clinical usefulness, radiation doses, limited accessibility, or inapplicability to spine and hip, therefore leaving several clinical needs still unmet. REMS is a clinically available technology for osteoporosis diagnosis and fracture risk assessment through the estimation of BMD on the axial skeleton reference sites. Its automatic processing of unfiltered ultrasound signals provides accurate BMD values in view of fracture risk assessment.

CONCLUSIONS

New approaches for improved bone strength and fracture risk estimations are needed for a better management of osteoporotic patients. In this context, REMS represents a valuable approach for osteoporosis diagnosis and fracture risk prediction.

Ultrasound-Based Estimates of Cortical Bone Thickness and Porosity Are Associated With Nontraumatic Fractures in Postmenopausal Women: A Pilot Study

Recent ultrasound (US) axial transmission techniques exploit the multimode waveguide response of long bones to yield estimates of cortical bone structure characteristics. This pilot cross-sectional study aimed to evaluate the performance at the one-third distal radius of a bidirectional axial transmission technique (BDAT) to discriminate between fractured and nonfractured postmenopausal women. Cortical thickness (Ct.Th) and porosity (Ct.Po) estimates were obtained for 201 postmenopausal women: 109 were nonfractured (62.6 ± 7.8 years), 92 with one or more nontraumatic fractures (68.8 ± 9.2 years), 17 with hip fractures (66.1 ± 10.3 years), 32 with vertebral fractures (72.4 ± 7.9 years), and 17 with wrist fractures (67.8 ± 9.6 years). The areal bone mineral density (aBMD) was obtained using DXA at the femur and spine. Femoral aBMD correlated weakly, but significantly with Ct.Th (R = 0.23, p < 0.001) and Ct.Po (R = -0.15, p < 0.05). Femoral aBMD and both US parameters were significantly different between the subgroup of all nontraumatic fractures combined and the control group (p < 0.05). The main findings were that (1) Ct.Po was discriminant for all nontraumatic fractures combined (OR = 1.39; area under the receiver operating characteristic curve [AUC] equal to 0.71), for vertebral (OR = 1.96; AUC = 0.84) and wrist fractures (OR = 1.80; AUC = 0.71), whereas Ct.Th was discriminant for hip fractures only (OR = 2.01; AUC = 0.72); there was a significant association (2) between increased Ct.Po and vertebral and wrist fractures when these fractures were not associated with any measured aBMD variables; (3) between increased Ct.Po and all nontraumatic fractures combined independently of aBMD neck; and (4) between decreased Ct.Th and hip fractures independently of aBMD femur. BDAT variables showed comparable performance to that of aBMD neck with all types of fractures (OR = 1.48; AUC = 0.72) and that of aBMD femur with hip fractures (OR = 2.21; AUC = 0.70). If these results are confirmed in prospective studies, cortical BDAT measurements may be considered useful for assessing fracture risk in postmenopausal women. © 2019 American Society for Bone and Mineral Research.

Association of breastfeeding and postmenopausal osteoporosis in Chinese women: a community-based retrospective study

Background

Postmenopausal osteoporosis (PMOP) has long been a pervasive public health concern. With the aging Chinese population, the prevention, assessment and management of postmenopausal osteoporosis were particularly important. During the breastfeeding, a large amount of Calcium loss from maternal bone for infants’ growth. However, whether this loss is completely reversible remains controversial. As the relationship between breastfeeding and postmenopausal osteoporosis is different from society to society and is not clear from the literature, the purpose of this study was to determine whether breastfeeding was an independent factor for the development of PMOP based on Chinese postmenopausal population.

Methods

A retrospective cross-sectional investigation was conducted at Tianjin Xiaobailou health Community Healthcare Center between December 2017 and June 2018. Postmenopausal women over the age of 50 who underwent the annual health examination or visited the center to perform bone densitometry as a part of routine screening for disease were recruited. A trained community nurse administered a questionnaire to all participants by face-to-face interview. Participants were questioned about age, BMI, Vitamin D and calcium intake, the history of smoking, drinking and fracture, age of menarche, age of menopause, the number of pregnancy, parity, feeding pattern (breastfeeding, artificial feeding and mixed feeding) and overall breastfeeding duration. BMD measurements were carried out using quantitative ultrasound (QUS) at the bilateral radius.

Results

A total of 202 women who met the inclusive and exclusive criteria were enrolled. Univariate analysis revealed that overall breastfeeding more than 24 months increased the risk of osteoporosis (OR 39.00, 95%CI 2.40–634.65, p = 0.010). However, multivariate estimate of the risk of osteoporosis by overall breastfeeding duration suggested that when controlling for age, BMI, the number of pregnancy and parity, the overall breastfeeding duration was not an independent risk factor for postmenopausal osteoporosis (OR 5.22, 95%CI 0.18–147.76, p = 0.333). Additionally, age (OR 1.16, 95%CI 1.05–1.29, p = 0.003), BMI (OR 1.26, 95%CI 1.04–1.54, p = 0.021) and the number of pregnancy (OR 1.80, 95%CI 1.08–2.98, p = 0.024) were significant associated with postmenopausal osteoporosis.

Conclusion

Breastfeeding was not associated with postmenopausal osteoporosis, while age, BMI and the number of pregnancy may contribute to increasing risk of postmenopausal osteoporosis in Chinese women.

Electronic supplementary material

The online version of this article (10.1186/s12905-019-0808-0) contains supplementary material, which is available to authorized users.

Prescreening for Osteoporosis With Quantitative Ultrasound in Postmenopausal White Women

OBJECTIVES

Calcaneal quantitative ultrasound (QUS) is a readily accessible and radiation-free alternative to dual-energy x-ray absorptiometry (DXA) for assessing bone mineral density (BMD). Results obtained from QUS measurement cannot directly be compared to DXA, since these techniques capture different bone-specific parameters. To identify individuals who are likely to have osteoporosis by DXA, device-specific thresholds have to be defined for QUS. This cross-sectional study evaluated the accuracy of QUS to identify postmenopausal women with osteoporosis, defined as a T score of -2.5 SDs or lower by DXA, and to calculate device-specific cutoff values for the QUS device investigated.

METHODS

We assessed BMD at the lumbar spine, bilateral femoral neck, and total hip sites with DXA and QUS parameters of the right and left calcanei in a cohort of 245 postmenopausal treatment-naïve women between 40 and 82 years. Correlation coefficients for BMD and QUS parameters were calculated. Receiver operating characteristic curves were generated, and areas under the curves (AUCs) were evaluated. Cutoff values for QUS were defined.

RESULTS

Calcaneal QUS had the ability to identify postmenopausal women with a T score of -2.5 or lower at the right hip (AUC, 0.887) and left femoral neck (AUC, 0.824). Cutoff values for the QUS T scores at the right (-1.455) and left (-1.480) calcanei were defined for screening purposes.

CONCLUSIONS

This study provides insights into the comparative performance of QUS with DXA. Considering the diagnostic accuracy of this modality in comparison to DXA, it can be recommended as a prescreening tool to reduce the number of DXA screenings.

Associations between radius low-frequency axial ultrasound velocity and bone fragility in elderly men and women

An exploratory study in elderly women and men from the Geneva Retirees Cohort indicates that low-frequency quantitative ultrasound measurement at the radius captures aBMD, bone size, and cortical tissue mineral density and might be used for screening purposes prior to DXA to evaluate fracture risk_. INTRODUCTION: The contribution of distal radius bone mineral density (BMD) and cortical microstructure to fracture risk has recently been demonstrated. In this exploratory study, we investigated whether low-frequency quantitative ultrasound measurement at the distal radius may capture the peripheral determinants of bone fragility assessed with dual-energy X-ray absorptiometry (DXA) and high-resolution peripheral quantitative computed tomography (HR-pQCT).

METHODS

Low-frequency velocity (V_LF) was measured at the radius using OsCare Sono®, a portable axial transmission ultrasonometer, in 271 community-dwelling postmenopausal women and men (age 71.5 ± 1.4 years) from the Geneva Retirees Cohort. Cortical (Ct) and trabecular (Tb) volumetric (v) BMD and microstructure at the distal radius were assessed by HR-pQCT, in addition to areal (a) BMD by DXA, at the same time point.

RESULTS

V_LF was highly correlated with aBMD at the distal third radius (r = 0.72, p < 0.001). For microstructure parameters, the highest correlation was observed with cortical area (r = 0.59, p < 0.001). V_LF also captured bone geometry (total area) and cortical tissue mineral density independently of aBMD. In models adjusted for age and sex, V_LF was significantly associated with prevalent low-trauma fractures [OR 95%CI for one SD decrease of V_LF 1.50 (1.05, 2.14), p = 0.024], with discrimination performance comparable to femoral neck or distal radius aBMD.

CONCLUSION

Measurement of V_LF at the radius captures aBMD, bone size, and cortical tissue mineral density and might be used for screening purposes prior to DXA to evaluate fracture risk_.

Speed of sound ultrasound: a pilot study on a novel technique to identify sarcopenia in seniors

OBJECTIVES

To measure speed of sound (SoS) with a novel hand-held ultrasound technique as a quantitative indicator for muscle loss and fatty muscular degeneration.

METHODS

Both calf muscles of 11 healthy, young females (mean age 29 years), and 10 elderly females (mean age 82 years) were prospectively examined with a standard ultrasound machine. A flat Plexiglas® reflector, on the opposite side of the probe with the calf in between, was used as timing reference for SoS (m/s) and ΔSoS (variation of SoS, m/s). Handgrip strength (kPA), Tegner activity scores, and 5-point comfort score (1 = comfortable to 5 = never again) were also assessed. Ultrasound parameters (muscle/adipose thickness, echo intensity) were measured for comparison.

RESULTS

Both calves were assessed in less than two minutes. All measurements were successful. The elderly females showed significantly lower SoS (1516 m/s, SD17) compared to the young adults (1545 m/s, SD10; p < 0.01). The ΔSoS of elderly females was significantly higher (12.2 m/s, SD3.6) than for young females (6.4 m/s, SD1.5; p < 0.01). Significant correlations of SoS with hand grip strength (r = 0.644) and Tegner activity score (r_s = 0.709) were found, of similar magnitude as the correlation of hand grip strength with Tegner activity score (r_s = 0.794). The average comfort score of the elderly was 1.1 and for the young adults 1.4. SoS senior/young classification (AUC = 0.936) was superior to conventional US parameters.

CONCLUSIONS

There were significant differences of SoS and ΔSoS between young and elderly females. Measurements were fast and well tolerated. The novel technique shows potential for sarcopenia quantification using a standard ultrasound machine.

KEY POINTS

• Speed of sound ultrasound: a novel technique to identify sarcopenia in seniors. • Measurements were fast and well tolerated using a standard ultrasound machine. • The novel technique shows potential for sarcopenia quantification.

AKAP11 gene polymorphism is associated with bone mass measured by quantitative ultrasound in young adults

Background: Due to the increased prevalence of osteoporosis and direct health care cost of osteoporosis-related fractures, there is a growing interest in identifying genetic markers associated with osteoporosis phenotypes in order to develop genetic screening strategies. We aimed to analyze the possible associations between calcaneal Quantitative ultrasound (QUS), a valuable screening tool for assessing bone status in clinical practice, and ZBTB40 (rs7524102, rs6426749), SP7 (rs2016266) and AKAP11 (rs9533090) genes. Methods: A cross-sectional study was conducted on 550 healthy individuals of Caucasian ancestry (381 females and 169 males, median age 20.46±2,69). Bone mass was assessed through QUS to determine broadband ultrasound attenuation (BUA, dB/MHz). Single-nucleotide polymorphisms (SNPs) in ZBTB40 (rs7524102, rs6426749), SP7 (rs2016266) and AKAP11 (rs9533090) were selected as genetic markers and genotyped using TaqMan OpenArray® technology. Results: Linear regression analysis revealed that rs7524102 and rs6426749 in ZBTB40, and rs9533090 in AKAP11 were significantly associated with the calcaneal QUS parameter after adjustments for age, sex, weight, height, physical activity, and calcium intake (p=0.038, p=0.012 and p=0.008, respectively). After applying the Bonferroni correction for multiple testing (p=0.012), only the association of rs9533090 in AKAP11 remained significant. Conclusion:AKAP11 gene (rs9533090) influences QUS trait in a population of Caucasian young adults. The rs9533090 SNP may be considered a factor affecting peak bone mass acquisition.