Tibial component for artificial knee joint

A tibial component for use with a femoral component for an artificial knee joint, said tibial component comprising:

• a plate section having, at an upper surface thereof, a pair of bearing surface parts which are adapted to be in sliding contact with said femoral component;
• a stem extending downwardly from a lower surface of said plate section;
• a pair of blade-like plicae extending obliquely posteriorly from said stem and said pair of blade-like plicae extending from said lower surface of said plate section downwardly to an end of said stem remote from said lower surface of said plate section to prevent said stem from being rotated about an axis thereof and for preventing said stem from being inclined in antero-posterior and medio-lateral directions;
• and
• said plate section having at a lower surface thereof a plurality of elongated grooves for improving affinity with respect to a surrounding bone, said grooves including a first group of grooves and a second group of grooves extending substantially perpendicularly to said first group of grooves.