Tibial trials with sliding spacers and method

A tibial trial comprising:

• a tibial tray having a perimeter, the tibial tray comprising a rim extending about a substantial portion of the perimeter;
• a spacer with a superior side and an inferior side, wherein the inferior side defines a periphery sized and shaped to contact the rim located on the tibial tray to restrict motion of the spacer relative to the tibial tray when connected to the tibial tray, the spacer comprising a first interlocking mechanism extending superiorly therefrom, the first interlocking mechanism including medial and lateral sidewalls and a plurality of rails extending laterally from the medial and lateral sidewalls of the first interlocking mechanism, the plurality of rails extending in an anterior to posterior direction, the plurality of rails defining a groove along the medial and lateral sidewalls of the first interlocking mechanism;
• an articular trial with an inferior side and with a superior side configured to interact with a femoral trial or a femoral implant, the articular trial being configured to be slid in an anterior to posterior direction between the spacer and the femoral trial or the femoral implant, the articular trial comprising a recess formed in the inferior surface thereof, the recess arranged and configured to receive the first interlocking mechanism, the articular trial further including a plurality of guide rails extending laterally into the recess, the plurality of guide rails extending in an anterior to posterior direction;
• and
• wherein when the articular trial is slid in an anterior to posterior direction between the spacer and the femoral trial or the femoral implant, the plurality of guide rails on the articular trial interlock with the grooves defined by the plurality of rails extending from the medial and lateral sidewalls of the first interlocking mechanism of the spacer without moving the femoral trial or femoral implant superiorly relative to the spacer.

A tibial trial comprising:

• a tibial tray having a superior portion, the tibial tray comprising a ridge extending across the superior portion;
• a spacer with a superior side and an inferior side, wherein the inferior side is sized and shaped to connect with the ridge extending across the superior portion of the tibial tray to restrict motion of the spacer relative to the tibial tray when connected to the tibial tray, the spacer comprising a first interlocking mechanism extending superiorly therefrom, the first interlocking mechanism including medial and lateral sidewalls and a plurality of rails extending laterally from the medial and lateral sidewalls of the first interlocking mechanism, the plurality of rails extending in an anterior to posterior direction, the plurality of rails defining a groove along the medial and lateral sidewalls of the first interlocking mechanism, the spacer further comprising a first stop within the groove and located at a posterior portion of the groove;
• an articular trial with an inferior side and with a superior side configured to interact with a femoral trial or a femoral implant, the articular trial being configured to be slid in an anterior to posterior direction between the spacer and the femoral trial or the femoral implant, the articular trial comprising a recess formed in the inferior surface thereof, the recess arranged and configured to receive the first interlocking mechanism, the articular trial further including a plurality of guide rails extending laterally into the recess, the plurality of guide rails extending in an anterior to posterior direction, the articular trial further comprising a second stop oblique to the guide rail;
• and
• wherein when the articular trial is slid in an anterior to posterior direction between the spacer and the femoral trial or the femoral implant, the plurality of guide rails of the articular trial interlock with the grooves defined by the plurality of rails extending from the medial and lateral sidewalls of the first interlocking mechanism of the spacer without moving the femoral trial or femoral implant superiorly relative to the spacer and the second stop is engageable with the first stop to limit movement of the articular trial relative to the spacer along the groove.