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[Bone density of calcaneus of 2769 healthy persons in Zhejiang province].

OBJECTIVE
To provide a scientific basis for the diagnosis and prevention of osteoporosis in Chinese populations.


METHODS
The stiffness index (STI) of the calcaneus was measured with the Achilles Express ultrasound apparatus made in USA among 2769 healthy persons, 1262 males and 1507 females, aged 10 to over 60, in Zhejiang province. The relationships between the STI and sex and age were analyzed.


RESULTS
The peak STI appeared in the age 20 - 24 among the males, and appeared in the age 15 - 19 among the females. Beyond these age periods the STI decreased along with the age. The STI values of the males aged over 54 were significantly higher than those of the females the same age. The speed of STI decrease of the females aged over 55 was higher than the males of the same age (P < 0.01). The prevalence of osteoporosis was higher in the females than in the males. The STI was negatively correlated with age, and positively correlated with height and body weight in both sexes. The practically measured T values were mostly significantly lower than the instrument' T values (with young adult Japanese as reference population).


CONCLUSION
There are significant relationships between STI and age, height, and body weight in both males and females. The distribution of bone mineral density of the reference population for the imported instrument does not completely accord with that of Chinese. It is necessary to establish a standard adaptable to the specific condition of Chinese.