Ultrasound velocity and cortical bone characteristics in vivo.

Axial transmission of ultrasound along cortical bone may reflect a combination of material and structural properties of long bone cortices. The goal of this study was to determine the association of speed of sound (SOS) with cortical density (CoD), cortical wall thickness (CWT), and total cortical area (CoA). Quantitative ultrasound (QUS) and peripheral quantitative computed tomography (pQCT) were used to measure the above variables in the distal third of radius and the midshaft of tibia in 51 postmenopausal women aged 62 to 71 years. Univariate regression analysis showed that the site-specific CoD accounted for 34% of the variability in the radial SOS and 29% of that in the tibial SOS (p0.…