Methods related to seating of bearing component on tibial tray

A method of inserting a bearing component onto a tibial tray via an incision providing access to a knee, the knee having an extensor mechanism, the method comprising:

• providing the tibial tray having a support surface sized to receive the bearing component;
• positioning the tibial tray within the knee via the incision;
• providing the bearing component having at least one concave articulating surface and an opposing distal surface;
• inserting the bearing component, while avoiding the extensor mechanism, through the incision in an anterior-medial insertion direction to position the distal surface of the bearing component atop the support surface of the tibial tray;
• seating the bearing component onto the tibial tray comprising rotating the bearing component about an axis of rotation displaced laterally of an anterior-posterior midline of tibial tray;
• and
• mating a boss and notch of the bearing component and the tibial tray, the boss and notch having corresponding shapes that are configured to allow for the rotating of the bearing component to provide a final alignment of the bearing component with the tibial tray, the boss and notch are configured to provide for a locking engagement of the bearing component with the tibial tray in the manner of a fixed-bearing prosthesis.

A method of inserting a bearing component onto a tibial tray via an incision providing access to a knee, the knee having an extensor mechanism, the method comprising:

• providing the tibial tray having a support surface sized to receive the bearing component;
• positioning the tibial tray within the knee via the incision, wherein the step of positioning the tibial tray comprises positioning the tibial tray including a boss including:
• a concave lateral side facing a lateral edge of the tibial tray,
• a convex medial side facing a medial edge of the tibial tray, and
• a boss rail projecting transversely from each of the concave lateral side and the convex medial side, the boss rail having an increasing thickness in a first direction from an anterior end of the boss towards a posterior end of the boss;
• providing the bearing component having at least one concave articulating surface and an opposing distal surface, wherein the bearing component comprises a notch shaped to receive the boss of the tibial tray;
• inserting the bearing component, while avoiding the extensor mechanism, through the incision in an anterior-medial insertion direction to position the distal surface of the bearing component atop the support surface of the tibial tray;
• and
• seating the bearing component onto the tibial tray, wherein the step of seating the bearing component onto the tibial tray comprises:
• advancing the boss of the tibial tray into the notch, and
• rotating the bearing component until the medial and lateral projecting rails of the tibial tray form a locking engagement with the medial and lateral grooves of the bearing component, respectively.