Three ultrasound parameters-broad band ultrasound attenuation (BUA), speed of sound (SOS) through the heel and average of standardized BUA and SOS (stiffness)-were measured with a LUNAR Achilles system (Lunar Corporation, Madison, WI, USA) in 9459 normal Japanese women (mean±SD 54.7±11.3yr, 15-90 yr) who have no history of ovariectomy, and 260 men (58.1±16.5 yr, 15-86 yr).
The bone mass values peaked in women aged 15-17 years (BUA 116±9, SOS 1572±23 and stiffness 97±11), and in men aged 15-16 (SOS 1590±20, stiffness 107±11) and in the age span 22-29 years (BUA 124±14).
The rates of bone loss were high in women aged 51-55 (stiffness 1.0%/yr), significantly high in the women who had been menopausal for less than 5 years (stiffness 2.0% yr).
We compared the mean values of the parameters in women with early menopause (≤45 yr) and late menopause (≥53 yr) more than 5 years after the menopause. In the early menopausal women, the mean BUA values at age 58-62, and those of BUA, SOS and stiffness at age 63-67 were significantly low (P<0.02) compared with the age-matched values in the late menopausal women, whereas no significant difference was observed between those in either of the two groups after 68 years of age.
There were significantly positive correlations between the 3 ultrasound parameters and height, body weight and obesity index, but SOS was not significantly correlated with body mass index.
These results indicate that the maximal bone mass in the os calcis is attained in very young women aged 17 or less and that loss in the calcaneus bone quality appears to be more dependent on menopause than aging in women 58-67 years old. In the older women, however, the loss of bone seems to be age-related.

Methods: Nineteen volunteers (16 men, three women) lifted a 60-kg doll from a seated position to a standing position. The first transfer was performed without the HAL for Care Support, and the second was performed with the HAL for Care Support assistive robot. We evaluated transfer performance, the visual analog scale (VAS) score for lumbar fatigue, and electromyogram analyses of the trunk and hip. Results: Four participants (two men, two women) succeeded with the HAL for Care Support even though they were unable to perform the task without it. The mean lumbar fatigue VAS score for all participants without the HAL for Care Support was 62 mm, while that with it was 43 mm. With lumbar assistance from the HAL for Care Support, subjective lumbar fatigue during the transfer decreased significantly. A power analysis indicated adequate statistical power to detect a difference in the VAS score for lumbar fatigue (0.99). The activity of the left gluteus maximus alone increased significantly during transfers with the HAL for Care Support. No adverse events occurred during use of the HAL for Care Support for transfers. Conclusions The HAL for Care Support was able to reduce lumbar load in a simulated patient transfer.