A tibial implant system has an ultra-high molecular weight polyethylene tibial insert (10) which can engage with either one of two tibial trays through differing means of engagement. The tibial insert includes a locking wire (12) and locking tab (13) disposed along an anterior surface (11) and a locking recess (15) disposed along a posterior surface (14). A first polymeric tibial tray (20) includes a bead (22) along an anterior wall (21) and an undercut area (24) along a posterior wall (23). A second metallic tibial tray (30) includes a plurality of barbs (32) along an anterior wall (31) and an undercut area (34) along a posterior wall (33).
