Experimental investigation on wear map evolution of ceramic-on-UHMWPE hip prosthesis

In the literature, wear damage of hip prostheses is typically expressed as volumetric wear. Details on wear distribution are rarely provided despite being fundamental to better understand the damaging process and improve implant design. This study presents a preliminary experimental investigation on the evolution of the wear map of hip replacements during wear testing. A ceramic-on-UHMWPE hip prosthesis was tested in-vitro and wear maps of the cup surface were measured throughout the test in a novel way, combining focus variation microscope inspections to the replica method. Wear maps revealed important characteristics of the damaging process not highlighted by the standard gravimetric procedure such as worn area location and shape as well as the progress of local damages.