Calcaneus and vertebrae bone mineral density values and fracture threshold

The calcaneus bone mineral density values (BMDs) of healthy Japanese women peaked at 20 to 25 years of age with 435 +/- 66 mg/cm2 (mean +/- S.D.), decreased 0.51% on the average every year thereafter until 45 years of age, 1.72% between 45 and 55 years (menopause) and 0.55% thereafter. The vertebrae bone mineral density value peaked at 30 to 35 years of age with 1.06 +/- 0.13 g/cm2 (mean +/- S.D.), decreased 0.67% on the average every year thereafter until 45 years of age, 1.23% between 45 and 55 years (menopause) and 0.70% thereafter. Mean -2.0 S.D. of the peak bone mass was considered appropriate as the fracture threshold for both the calcaneus and vertebra, judging from the BMDs of osteoporosis patients.