Mechanical properties of vertebrae: An evaluation of the mature ovariectomized rat model of post-menopausal osteoporosis

Ovariectomized rats were used to model the loss of bone and the reduction of mechanical strength of the vertebrae due to osteoporosis in humans. The relative contributions of the cortical shell and cancellous interior portion of the vertebrae to the mechanical behavior of the bones were evaluated. It was shown that ovariectomy reduced the mean density of the bones by 5% compared to the control counterparts. It also decreased the compressive strength of the vertebral bodies. In addition, structural changes were observed in the cancellous bone. These observations are parallel to those observations in humans, particularly in post-menopausal women who have succumbed to osteoporosis as a result of lower estrogen levels in their bodies.