Bone quality assessment by quantitative ultrasound of proximal phalanxes of the hand in healthy subjects aged 3--21 years.

Bone quality by quantitative ultrasound was assessed in 1083 (587 males) healthy white subjects aged 3--21 y. Amplitude-dependent speed of sound (AD-SoS) through the distal end of the first phalanx diaphysis of the last four fingers of the hand was measured by an ultrasound device (DBM Sonic 1200, IGEA, Carpi, Italy). Mean AD-SoS values increased progressively from 3 to 21 y (males, 1845.9--2119.1 m/s, p < 0.0001; females, 1842.3--2098.8 m/s, p < 0.0001). They did not differ (p = NS) between sexes up to age 11, but females showed higher (p < 0.05 - p < 0.0001) AD-SoS values than males in age groups 12, 13, and 14 y. There was no difference (p = NS) of AD-SoS values between sexes in pubertal stages 1, 2, and 5, but females had higher mean AD-SoS values than males in stages 3 (p < 0.01) and 4 (p < 0.001). Independent predictors of AD-SoS were weight, body mass index, pubertal stage, and mean width of fingers in males, and age, pubertal stage, and mean width of fingers in females (p < 0.01 - p < 0.0001). However, 7.8% in males and 3.6% in females of the increment of AD-SoS values can be related to the finger anatomy alone. AD-SoS values probably reflect the architectural organization of growing bone or changes in bone elasticity. Increased bone density and size may be additional factors influencing AD-SOS: Measurement of AD-SoS at the hand phalanxes may be a simple, noninvasive, and radiation-free technique to assess bone quality in children.