Methods, compounds, and kits for the diagnosis or screening of osteonecrosis are described, and the development of animal models for COL2A1 function in osteonecrosis is put forth. Novel mutations in the COL2A1 gene are identified that are associated with avascular necrosis of the femoral head. Methods of treatment of osteonecrosis and avascular necrosis of the femoral head, including gene therapy approaches comprising introduction of COL2A1 nucleic acid are contemplated.