Bearing Surfaces in the Hip Joint Prosthesis: Past, Present and Future

Total hip arthroplasty (THA) is the replacement of the hip joint by artificial prosthesis. This surgery is one of the most successful orthopaedic surgeries. The most important challenge to the THA is bearing surface of these implants, which is closely related to the survival of the prosthesis. Following the introduction of the first successful implant in THA, there has been great progress in implant production, by increasing the power and reducing the friability and wear of the bearing surfaces. The wear particles can remain in the host tissue, generate osteolysis and reduce the implant survival. These problems with bearing surfaces have led to creation of other bearing surfaces such as metal-on-polyethylene, metal-on-metal, ceramic-on-ceramic and ceramic-on-polyethylene with improved characteristics. Such types of implants can be used for young and more active patient, in addition to the elderly who is less active. In the present review, the different type of bearing surfaces with their advantages and disadvantages has been discussed.