Performance of HR-pQCT, DXA, and FRAX in the discrimination of asymptomatic vertebral fracture in postmenopausal Chinese women

Abstract

Summary Volumetric bone density (vBMD) and trabecular microarchitecture measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) can discriminate the patients with high risk of asymptomatic vertebral fracture (VF) in postmenopausal Chinese women. These findings suggested that HR-pQCT could provide additional information on bone quality of the patients with asymptomatic VF. Introduction Although there were several studies using HR-pQCT to investigate asymptomatic VF, it remains uncertain if HR-pQCT parameters can discriminate asymptomatic VF patients, especially in Chinese population. The purpose of this study was to investigate whether bone quality measured by HR-pQCT could discriminate asymptomatic VF independent of hip areal bone mineral density (aBMD) measured by dual-energy x-ray absorptiometry (DXA) and fracture risks evaluated using built-in Fracture Risk Assessment Tool (FRAXBMD). Methods This is a nested case–control study. One hundred seventy-five ambulatory Chinese postmenopausal women aged 60–79 years were retrieved from Normative Reference Standards (NRS) cohort in Hong Kong. DXA was used to identify VF from lateral spine images (VFA) using Genant’s semi-quantitative method. Major osteoporotic fracture risk was calculated using FRAX tool. HR-pQCT was used to assess vBMD, microarchitecture, and estimated strength at both distal radius and tibia. Comparison of HR-pQCT parameters between asymptomatic VF and control was performed using covariance analysis. Logistic regression analysis was performed for calculating the adjusted odds ratio (OR) with 95% confidence intervals (CI) of fracture status as per SD decrease in HR-pQCT parameters. Results Women with asymptomatic VF were older than those of the control in our NRS cohort. Nevertheless, after adjusted for covariance, asymptomatic VF showed significantly lower trabecular vBMD (Tb.vBMD) at radius but higher SMI at tibia as compared with those of the control. Tb.vBMD at radius yielded the highest value of area under the curve (AUC) as compared with total hip aBMD and FRAXBMD. However, no significant difference was found among each other. Conclusion Tb.vBMD at the radius and SMI at the tibia provided by HR-pQCT can discriminate asymptomatic VF independent of hip aBMD and FRAXBMD by DXA in postmenopausal women.

Muscle plays a more superior role than fat in bone homeostasis: A cross-sectional study of old Asian people

“…The distal radius and distal tibia (non-dominant and non-fractured) of participants were scanned by HR-pQCT (XtremeCT I, Scanco Medical AG, Switzerland) using the standard scanning protocol (60 kVp, 900 μA, 100 ms integration time, isotropic voxel size 82 μm). The details of the HR-pQCT operational procedures and the image quality grading of HR-pQCT for motion artifact were illustrated in previous studies ( 18 , 19 ). Daily phantom calibration was performed to monitor the stability of the HR-pQCT system.…”

“…Trabecular thickness (Tb.Th, mm) was derived by standard histomorphometry methods ( 24 ). For cortical bone analysis, cortical thickness was measured directly by a distance-transform method and intracortical pores in the binary cortex image were eliminated ( 19 ). Bone strength was estimated in terms of stiffness (kN/mm) by micro-finite element analyses (μFEA) on three-dimensional images of the distal radius and tibia using a built-in Image Processing Language software of HR-pQCT (IPL-FE v1.15, Scanco Medical).…”

“…Bone strength was estimated in terms of stiffness (kN/mm) by micro-finite element analyses (μFEA) on three-dimensional images of the distal radius and tibia using a built-in Image Processing Language software of HR-pQCT (IPL-FE v1.15, Scanco Medical). The specific conditions of the software operation were illustrated in previous studies ( 18 , 19 ). Whole bone stiffness (kN/mm) was evaluated by performing a uniaxial compression test with 1000 N load and an apparent strain of 1%.…”

“…Daily phantom calibration was performed to monitor the stability of the DXA system. CV for femoral neck, total hip, and lumbar spine aBMD in our center was 1.36%, 1.19%, and 1.01%, respectively (19). Five elderly volunteers were included to assess the reliability of DXA examination.…”

“…standard scanning protocol (60 kVp, 900 mA, 100 ms integration time, isotropic voxel size 82 mm). The details of the HR-pQCT operational procedures and the image quality grading of HR-pQCT for motion artifact were illustrated in previous studies (18,19). Daily phantom calibration was performed to monitor the stability of the HR-pQCT system.…”