Patent ID: 7695519

Claim:
A modular tibial implant comprising: a polymeric bearing component having an inferior surface, a tibial baseplate having a superior surface for receiving the inferior surface of the polymeric bearing component and having a medial side, a lateral side an anterior side and a posterior side with a plate having a distally facing bone contacting surface, the superior surface extending between said sides of said baseplate, said plate including an opening therein, said bone contacting surface having a distally facing portion having a u-shaped receptacle therein open to only one side of said baseplate said receptacle located intermediate the bone contacting surface and the superior surface of the baseplate and the opening open to the bone contacting surface, the receptacle having a u-shaped groove formed on an inwardly facing peripheral surface thereof; a modular bone engagement element having a distal bone engaging portion and a u-shaped flanged proximal coupling portion for slidable insertion into said receptacle in a direction generally parallel to said bone contacting surface, the flanged coupling portion having a u-shaped tongue extending around an outer periphery thereof for being received within the groove of the u-shaped receptacle; a locking element for engaging said flanged proximal coupling portion of said bone engagement element after the bone engaging element has been slidably inserted into said receptacle to prevent disassembly thereof from said baseplate, wherein said receptacle includes a pair of spaced rails forming grooves for receiving edges of said flanged proximal coupling portion and said modular bone engagement element is a keel or a stem, said keel includes a first fin extending radially outwardly from said stem portion at an angle to said medial side of said baseplate and a second fin extending radially outwardly of said stem at an angle to said lateral side of said baseplate wherein said baseplate bone contacting surfaces includes a pair of inferiorly extending ribs for engaging a proximal end portion of each of said first and second fins.