Animal models of osteonecrosis

Nonhuman animal research is advantageous only if the ethical dilemma surrounding the use of live animals for this purpose is resolved in one's laboratory and institution. Investigators have struggled in creating an animal model of the disease that realistically mimics the natural course of the disease in humans. It has been exceptionally difficult to develop a model that proves capable of progressing to the end-stage condition of frank mechanical collapse that occurs in humans. This paper attempts to describe the significant findings of various animal models, their advantages and disadvantages, and their key methodologies that could assist in the development of that elusive ideal model.