Age and menopause-related changes in phalangeal bone density of Japanese women, measured by a digital image processing method

Abstract

The bone density (BD), phalangeal index (PLI), and metacarpal index (MCI) of the proximal phalangeal and metacarpal bones of the index finger of the nondominant hand were measured, using a digital image processing (DIP) method, in a total of 345 normal Japanese women. In this study, two different locations were measured and the BD, PLI, and MCI decreased significantly after the age of 50 years (P, 0.01 vs values for women in their third decade). The BD, PLI, and MCI of the proximal phalangeal and metacarpal bones showed a significant decrease in postmenopausal groups compared with the pre-menopause group (P, 0.01), which indicated that not only trabecular bone but also cortical bone had an accelerative bone loss in the postmenopausal women. The BD in proximal phalangeal and metacarpal bones decreased by 0.69% and 0.74% / per year, respectively, and there were no significant differences between these annual decreases. The BD of proximal phalangeal bone had a good correlation with that of the metacarpal bone (r 5 0.77; P, 0.01), which suggested that the measurement of proximal phalangeal BD was as useful as the measurement of metacarpal BD in screening for osteoporosis (coefficient of variation; CV, 0.64%). The data suggest that DIP has a potential application in screening for osteoporosis.