Degree Name

BS in Biomedical Engineering


Biomedical and General Engineering Department


Scott Hazelwood


Recognized as the most common type of bone disease in humans, osteoporosis poses a major health threat to roughly 28 million Americans [1]. In women, the leading cause of osteoporosis is known to be a drop in estrogen during the time of menopause. Thus, it becomes essential to acquire a better understanding of postmenopausal osteoporosis, as many individuals desire a longer lifetime and an improved quality of life for the elderly. To further current knowledge of postmenopausal osteoporosis and help develop methods of overcoming it, it is important to find an appropriate animal model.

In this study, pretreated ovine compact bone is analyzed using histomorphometry to see if this type of animal model can be used to model osteoporotic bone in women experiencing menopause. Ready-made radiographs of ovine compact bone taken from the radius and ulna of 14 sham-ovariectomized sheep (control) and 14 ovariectomized sheep (OVX), sacrificed after 3 months in either the winter or fall seasons, were used to study the consequences of seasonal, anatomical, and hormonal variation on ovine bone remodeling. Three-way ANOVA analyses were performed to determine seasonal, anatomical, and hormonal interaction effects on the following variables (quantified via histomorphometry): bone volume to tissue volume ratio, average percent of tissue and material remodeling, average secondary osteonal radius, and number of cement line interfaces (CLI).

Anatomical and hormonal variations were found to have individual effects on average percent remodeled tissue and material, with 95% confidence. Tukey’s tests showed that estrogen depletion of OVX sheep caused significantly higher percent remodeled tissue and material averages than control sheep. In addition, there were seasonal and anatomical interaction effects on average CLI in both tissue and material, and a seasonal effect on average osteonal radius.