Regional variations in histomorphometric bone dynamics from the skeleton of an osteoporotic woman.

Histomorphometric evaluation of bone formation in an intravital tetracycline-labeled skeleton of a suddenly deceased osteoporotic woman is presented. The 24 skeletal sites investigated displayed substantial regional variations which, for two out of four cortical bone dynamics and all trabecular bone dynamics, were significantly higher than the intraspecimen variation. Poor agreement was found between bone formation in left- and right-sided iliac crest specimens. Furthermore, no agreement was found between trabecular bone formation and amount of hematopoietic bone marrow. With all the limitations that the study of a single patient involves it is suggested that bone biopsy in individual patients should not be the only basis for therapeutic decisions in postmenopausal osteoporosis; amount of hematopoietic marrow does not seem to influence bone formation; and bone formation in the skeleton displays large regional variations, which are larger for the fraction of labeled surfaces than for appositional rate.