The role of quantitative ultrasound in predicting osteoporosis defined by dual X-ray absorptiometry

The aim of this study was to establish whether quantitative ultrasound (QUS) parameters could identify patients classified as osteoporotic and osteopenic on the basis of dual energy X-ray absorptiometry (DEXA). One hundred and twenty-three patients (39 male, 84 female) with osteoporosis and suspected of having osteoporosis were included in this study. Broadband ultrasound attenuation (BUA) and speed of sound (SOS) were measured and bone mineral densities (BMD) of the lumbar spine and left hip was measured by DEXA. Subjects were classified into three groups (normal, osteopenic and osteoporotic) on the basis of BMD T-scores measured by DEXA. QUS parameters of the osteoporotic group were significantly lower than those of osteopenic and normal groups; there was no difference in QUS parameters between the normal and osteopenic groups. Correlations of both right and left SOS and BUA with the spine and femoral neck BMD were moderate (r = 0.343-0.539, P < 0.001). There was also reasonable correlation between DEXA and QUS T-scores (r = 0.364-0.510, P < 0.001). QUS had a sensitivity of 21% and a specificity of 95% for diagnosing osteoporosis. We concluded that, although DEXA and QUS parameters were significantly correlated, QUS parameters can not predict osteopenia as defined by DEXA, and sensitivities and specificities of QUS parameters were not sufficiently high for QUS to be used as an alternative to DEXA.