Alternative bearing surface options for revision total hip arthroplasty.

Despite the overall success of total hip arthroplasty (THA), there has been an increase in the rate of revision hip surgeries performed each year in the United States. These revision surgeries result in several billion dollars in health care costs. Bearing surface wear can result in the need for revision surgery through a variety of mechanisms. Many implant failures necessitating the need for revision surgeries occur secondary to dislocations, which are often related to prothesis wear and eventual loosening of the components. Wear also can lead to osteolysis and may play a role in aseptic loosening. Specific concerns regarding the wear rates of metal-on-polyethylene (the most common bearing surface) have encouraged the manufacture of newer polyethylene implants with improved wear properties, as well as alternative bearing surfaces. The goal is to improve the durability of revision implants and/or reduce the incidence of revision THAs. Revision arthroplasty involves using alternative surfaces, such as replacing the metal femoral head with a ceramic component or changing the entire prosthesis to a metal-on-metal or ceramic-on-ceramic articulation. It is important to review the characteristics of these alternative bearing surface options and their contributions to improved THA tribology and prolonged prosthesis longevity. The choice of a bearing surface for a revision THA should consider factors such as the patient's age and activity level, the cost of the implant, and both the surgeons' and patients' preferences. Although laboratory studies and small clinical trials have generated optimistic results for these alternative implants in vitro and in vivo, much still needs to be learned about the long-term performance of these materials in patients after total hip revision surgery.