The correlation between calcaneus stiffness index calculated by QUS and total body BMD assessed by DXA in Chinese children and adolescents

Abstract

Few studies have shown comparison data between calcaneus stiffness index (SI) calculated by quantitative ultrasound (QUS) and bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) in the Chinese population. This study was aimed to examine the correlations between calcaneus SI calculated by QUS and total body BMD and bone mineral content (BMC) measured by DXA in Chinese children and adolescents. We measured the total body BMD and BMC using Lunar Prodigy (GE Healthcare), and speed of sound (SOS), broadband ultrasound attenuation (BUA), and a calculated SI of the left os calcis using Lunar Achilles Express (GE Healthcare) in 392 healthy Chinese schoolchildren and adolescents aged 5-19years. The short-term precision for DXA was 0.5% for total body BMD. The precision for QUS was 1.8% for SI, 2.9% for BUA, and 0.4% for SOS. Pearson's correlation coefficients (r) were calculated to assess the possible correlations between the total body BMC by DXA and SI calculated by QUS. There were significantly positive correlations between SI of the left os calcis and total body BMD (r=0.693, p<0.001, n=392) and BMC (r=0.690, p<0.001, n=392). For all the subjects, significant positive correlations were observed between the calcaneal SI and the age, weight, height, BMI, total body BMD, total body BMC, total body lean mass, and total body fat mass, with r ranging from 0.310 (total body fat mass) to 0.693 (total body BMD) (p<0.001, n=392). In conclusion, QUS bone densitometry is a useful measuring method showing the physiological bone development in childhood and adolescence.