Bearing component for artificial knee joint

A bearing component (200) for an artificial knee joint, the bearing component comprising:

• a body part (210) having a plane shape that is oval as a whole, having an indentation portion (211) formed by depressing a part of a rear side of the body part to a predetermined depth toward a center of the body part;
• a protruding portion (220) protruding from a top side of the body part (210) to a predetermined height and configured to be introduced into an opening of a femoral component;
• a coupling portion (230) provided on a bottom surface of the body part (210) opposite to the protruding portion (220), and including:
• a coupling protrusion (250) formed on a central portion of the bottom surface of the body part,
• wherein the central portion of the bottom surface of the body part includes the center of the body part, and
• wherein the coupling protrusion (250) includes
• a front part disposed at a position forward of the center of the body part,
• a left part extending from the left end of the front part toward the indentation portion of the body part, wherein a portion of the left part is disposed at a position rearward of the center of the body part, and
• a right part extending from the right end of the front part toward the indentation portion of the body part, wherein a portion of the right part is disposed at a position rearward of the center of the body part,
• wherein each of the front, left, and right parts of the coupling protrusion (250) has a bottom thickness greater than a top thickness, such that a groove is formed at a top portion of each part,
• wherein the grooves of the left and right parts are open to face each other, and the groove of the front part is open to face the indentation portion (211);
• and
• an engagement surface (231) having a plate shape as a whole with a predetermined height to form a step difference from the bottom surface of the body part, the engagement surface (231) being formed on left, front, and right sides on the bottom surface of the body part and being not formed on the central portion and near the indentation portion (211) of the bottom surface of the body part such that the engagement surface (231) surrounds the coupling protrusion (250),
• wherein the coupling portion (230) provides a dovetail type locking mechanism formed by the grooves of the left, front, and right parts, having a truncated cone or shape that gradually widens toward the indentation portion, and an air gap (242) is formed between the coupling protrusion and the engagement surface (231) along outer surfaces of the coupling protrusion such that where an accommodating portion (340) of a tibial component (300) is engaged, the air gap provides a free space in which the coupling protrusion (250) is configured to be retracted.