Trabecular and total bone densities were determined by quantitative
computed tomography in patients with untreated postmenopausal osteoporosis
and in normal premenopausal and postmenopausal women. A special procedure
was used for precise low-dose examinations of the distal end of the radius
and the distal end of the tibia. The results indicate that the trabecular
bone density of the peripheral skeleton is a reliable index of
postmenopausal osteoporosis. In general, osteoporotic patients could be
distinguished from patients with age-related bone loss based on differences
in the magnitude of the decrease in trabecular bone density. Serial
determinations of trabecular bone density in individual patients indicated
that trabecular bone loss in postmenopausal osteoporotic patients shows a
step-wise pattern in which phases of relative stability are followed by
brief phases of bone loss. Quantitative computed-tomography measurements of
bone density should provide a better understanding of the pathogenesis of
postmenopausal osteoporosis and be useful in the assessment of different
methods of treatment.