The bone mineral content (BMC) and the cortical thickness at the distal radius and at the II metacarpal were assessed in growing individuals (167 females and 158 males) by radiometric and quantitative roentgen microdensitometric methods. BMC adjusted for age and pubertal status was significantly higher in males than in females. However, the BMC corrected for bone volume (volumetric bone density, g/cm3) and the metacarpal cortical index (cortical area/total area) were identical in males and females. BMC rose progressively with age, approaching a plateau by the end of puberty. Lower but still significant increases with age were also observed for volumetric bone density of the metacarpus and the metacarpal index. These increases were also most marked by the end of pubertal maturation and might be related to diminution of bone turnover.
Conclusion: This study provides the normative data of bone mass in growing individuals by making use of a reasonably accurate and easily available technique. The results obtained indicate that most of the differences between males and females and the changes with age are related to changes in skeletal dimension rather than density.