Tibial prosthesis

Abstract

A tibial prosthesis, and, particularly, a fixed bearing tibial prosthesis has a two-pronged securement mechanism. The securement mechanism may or may not be angled. Advantageously, the securement mechanism, working alone or in cooperation with other securement features, minimizes micromotion between the tibial tray and tibial bearing component.

What is claimed is: 
     
         1 . A tibial prosthesis for replacing at least part of a natural knee of a body, the body defining a sagittal plane which centrally separates the body into right and left halves, said tibial prosthesis comprising:
 a bearing component comprising:
 at least one concave articulating surface; 
 a distal surface opposite said concave articulating surface; and 
 a notch formed in said distal surface, said notch defining a longitudinal axis, said longitudinal axis defining an offset axis angle relative to the sagittal plane, said offset axis angle ranging from greater than zero degrees to about 90 degrees; and 
   a tibial tray comprising:
 a support surface capable of supporting said bearing component, said support surface having a lateral edge and a medial edge opposite said lateral edge, and 
 a boss having an a longitudinal axis, said longitudinal axis angled with respect to the sagittal plane, 
   said boss lockingly engageable with said notch along said offset axis angle to lock said tibial tray to said bearing component.