A new preclinical femoral head osteonecrosis model in sheep.

Abstract

INTRODUCTION: Animal models have been used as insight into the pathogenesis of osteonecrosis, even though most have failed to reproduce all stages of human disease, limiting progression in experimental treatment modalities. A new surgically induced animal model of femoral head osteonecrosis in sheep is presented. METHOD: Osteonecrosis was achieved using an improved method of intracephalic cryogenic lesion by means of a cryoprobe and vascular ligation. RESULTS: Histologic findings at 6 and 12 weeks showed progression to advanced stage osteonecrosis. MRI, the gold standard in diagnosis and follow-up in human osteonecrosis showed concordant results with histology. CONCLUSION: Our model can therefore be used as a preclinical femoral head osteonecrosis model in an easily accessible animal to assess biological treatments with MRI.