Tribology and total hip arthroplasty implants.

Define tribology and discuss its effect on total hip arthroplasty (THA). Tribology is defined as the science of interacting surfaces in relative motion and includes the principles of friction, lubrication, and wear of implant materials. Tribology of the articulating materials in THA is the most important issue for long-term survival of the implants because the fixation of implants either with or without cement has reached excellent long-term survival rates up to 20 years. Because the long-term success of an implant is based on permanent fixation and wear of the articulation, concerns about wear and osteolysis have highlighted the importance of tribology in THA.