Bone Mineral Density in Japanese Children and Adolescents

Abstract

Lumbar bone mineral densities (BMD) and total bone mineral densities (TBMD) were examined in 779 Japanese children and adolescents aged 6 to 22 years. Peak bone masses assessed by lumbar BMD (BMDL2-4) were 1.05 ± 0.12 g/cm² in females aged 18-20 years, and 1.07 ± 0.11 g/cm² in males aged 20-22 years. Taking into consideration Seino's data, we made a standard curve for BMDL2-4 for both sexes. Applying the standard curve for BMDL2-4, we calculated incremental values of BMDL2-4 every 3 months. Maximum increase rate of BMDL2-4 for 3 months was 0.020 g/cm² in females at age 11 yr 3 months, and 0.018 g/cm² in males aged 13 yr. Changes in BMD in both sexes in 10 regions including head, both arms, bilateral ribs, thoracic-spine (T-spine), lumbar-spine (L-spine), pelvis and both legs in subjects from 8 to 18 yr old were also measured. BMD for the head was highest among the ten regions. BMD in the arms, legs and spine did not differ in children under 10 yr of age. BMD in the right arm was higher than that in the left arm in both sexes from age 11 yr.