A prosthetic assembly comprising: a body portion; first and second flanges provided on a rim of the body portion; the first and second flanges being provided with first and second openings respectively; and a bridging member connectable to the first and second flanges such that the member spans between the first and second flanges, the member being provided with a third opening; wherein the first, second and third openings are suitable for receiving first, second and third bone attachment members respectively.