Decreased bone formation in osteoporotic patients compared with age-matched controls.

In order to study trabecular bone remodeling in postmenopausal osteoporosis we compared bone biopsies of 44 osteoporotic women aged 50-70 to those of 23 nonosteoporotic women, matched for age, who had a bone biopsy during anesthesia for knee arthritis. Trabecular bone volume, mean wall thickness, osteoblastic surfaces, labeled surfaces, and bone formation rate were decreased in osteoporotic women compared with control women. The osteoclast number and the osteoclastic surfaces were the same in the two groups. The normal distribution of the histomorphometric static parameters in osteoporotic patients did not allow the separation of subgroups. These data indicate that decreased bone formations is a major contributing factor leading to trabecular bone loss in postmenopausal osteoporosis.