Abstract: A device for use with an acetabular socket prosthesis which has an outer rim of predetermined size. The device comprises an outwardly extending removable location and/or sealing element adapted to surround the outer rim of said cup with which it is to be used during implantation thereof.

Abstract: An apparatus for performing prosthesis surgery has a phantom implant component. Elements are provided for holding said phantom component accurately and stationary relative to a cavity in a bone. The phantom component has a tapered insert portion, the dimensions of which are identical to the insert portion of an implant component which is to be fitted. A method of performing prosthesis surgery is included which uses the apparatus set forth above which includes preparing an opening in a bone with cement, inserting the insert portion of the phantom component, allowing the cement to at least partially set, removing the phantom component, inspecting the cement and then inserting the implant component with the identical insert portion dimensions.