The P.F.C. Sigma tibial tray component being assessed in this study is made of Cobalt Chrome (CoCr). The new CoCr tibial tray has the same design geometrically as the original titanium (Ti) tray, however, it features a highly polished top surface where it is joined to the polyethylene. This polished surface is designed to decrease the coefficient of friction between the polyethylene and the tray, thus minimizing backside wear. A comparative clinical study will be conducted to evaluate long-term clinical and radiographic data between geometrically identical cemented implants using GVF and crosslinked polyethylene tibial tray bearing inserts in Total Knee Arthroplasty (TKA) using the P.F.C. Sigma Total Knee System. Patients will be assigned to study treatment groups at random if they meet specific demographic and pathophysiologic criteria for cemented total knee arthroplasty. The anticipated duration of this investigation is a minimum six years, which includes a one-year enrollment phase.