A method and apparatus for a prosthesis. At least a portion of the
prosthesis is made from a ceramic that is treated with ion implantation,
which causes a controllable, bilateral compressive stress of the ceramic.
A diamond-like-coating (DLC) can be coated on the ceramic and in the same
chamber as the ion implantation. After treating by ion implantation and
coating with DLC, the ceramic will be strengthened and have a low
coefficient of friction and thereby be made much less likely to fracture
under load.