[Clinical evaluation of ultrasonic measurement of the calcaneal bone]

We measured the speed of sound (SOS) and broadband ultrasound attenuation (BUA) in the calcaneal bone and compared those values with bone mineral density (BMD) as assessed by single X-ray absorptiometry and dual energy X-ray absorptiometry. Calcaneal speed of sound and broad band ultrasound attenuation showed an earlier decrease with age than lumbar BMD, Calcaneal SOS and BUA correlated well with calcaneal BMD. Calcaneal SOS correlated more closely with neck BMD than lumbar BMD measured by DXA. Furthermore, measurement of calcaneal SOS is more useful than measurement of lumbar BMD to evaluate femoral neck BMD, which might be very important for clinical purposes. Both body weight and height correlated well with calcaneal BMD but not so well with calcaneal SOS or BUA. As ultrasound emits no radiation, we can use it without the restriction of radiation protection.