Bone repair in osteoporotic bone: postmenopausal and cortisone-induced osteoporosis.

Although osteoporosis has been the subject of a considerable number of publications in recent years, very few studies have investigated the effects of osteoporosis on the process of tissue repair. Most of the studies are based on animal data, using the ovariectomized rat model, and in most cases, fractures were obtained by femoral osteotomy. This model is imperfect in several aspects to fit with postmenopausal osteoporosis which is a complex, multifactorial disorder. Furthermore, a surgically induced fracture is not exactly the same as a fracture which occurs as a result of bone fragility. However, and despite contradictory results in some of the studies, in ovariectomized rats a delay in bone consolidation has been reported in the model, associated locally with a decrease in bone mineral density and mechanical resistance. Very few human data are available, which confirm the existence of a delay in consolidation subsequent to femoral fractures in aged patients compared to young patients.