Prospective Study to Evaluate the ConforMIS iTotal^® (PS) Knee Replacement System

The purpose of this study is to gather information over time about the performance of a customized knee implant in patients who have osteoarthritis of the knee. The implant being used in this study is already cleared by the FDA for use in patients with knee osteoarthritis. The study is only to collect information over time about how patients do after receiving the implant.