Pathophysiology of osteoporosis

The pathogenesis of osteoporosis is complex and multifactorial. Alterations in bone density almost certainly represent the final common pathway by which pathologic factors affect risk of future osteoporotic fracture. The interplay of various physiologic processes, which result in peak bone mass, and maintenance of adult bone mass are key to understanding the pathogenesis of the disease. Changes in hormonal status, and in particular estradiol, clearly are important factors in both formation and resorption of bone in men and women. Perturbations in growth hormone activity, musculoskeletal function, dietary intake of calcium and vitamin D, and genetic determinants are also important pathogenic factors. Sorting out this complex interaction will challenge investigators and clinicians well into the next century.