Since the first total hip arthroplasty (THA) in 1938, THA evolved and developed into one of the major concentrations of orthopaedic research. The typical hip implant device used today incorporates a femoral and an acetabular component that serve to replicate the anatomical and mechanical functions of the natural hip joint. However, several problems exist that can effect the function of the implant device. Wear in the polyethylene liner of the acetabular component of the total hip replacement device is known as one of the major factors that affects the longevity of total hip replacement devices. Both manual and computer-aided techniques have been developed to measure linear and volumetric polyethylene wear in two and three-dimensional directions. This study aims to develop a software package that will accurately measure in vivo polyethylene wear after total hip arthroplasty and can be applied to determine the factors that lead to polyethylene wear.