Abstract
By direct measurement on the roentgenograms and densitometry in comparison with aluminum step-wedge, all metacarpals of both hands were studied. Thickness of the cortex declined with advancing age especially in females after middle age so that a significant difference between males and females was obtained after the age of 60. The decrease in cortical thickness was especially pronounced in the first and fifth metacarpals resulting in a highly significant correlation between age and peripheral-central ratio of the cortical thickness in both sexes. The density of metacarpals was definitely lower in females than in males above the age of 30, indicating the earlier onset of the decrease in density than that of the thinning of the cortex. A negative correlation was found between age and metacarpal density in females but not in males.
