Patellar complications in total knee replacement.

Over the past 26 years there have been marked changes in total knee arthroplasty components. Combinations of metal and polyethylene have been used in a variety of ways in the development of the three major components of the knee prosthesis. The metal-backed patellar implant that was considered state-of-the-art in the early 1980s soon came under criticism due to the high rate of failure and subsequent revision. A closer look at patellar resurfacing may suggest that some patellar compartments do just as well without being resurfaced.