Host factors that affect outcome of total hip arthroplasty

Investigations into risk factors influencing success of total hip arthroplasty have focused primarily on the type of prosthesis and surgical technique. Rapid polyethylene wear was found to be an important contributor to aseptic fixation failure. However, because prosthesis design is now near perfect, the effect of prosthesis-related factors on survival of the implant has declined. The extreme variability in functional outcomes and revision rates, even within groups implanted with the same prosthesis and at the same institution, indicates the importance of looking beyond prosthetic factors. In today’s Lancet Seneki Kobayashi and colleagues report that the two most important host factors contributing to the survival of the hip implant are poor bone quality (manifest as atrophic osteoarthritis) and poor structure of the hip (stovepipe canal).