Modular implant provisional

A provisional tibial component for a knee joint prosthesis having modular augmentation block, the provisional tibial component comprising;

• a tibial tray having a proximal surface configured for contact with a bearing insert and a distal surface configured for contact with prepared bone surface, the tibial tray including an anterior surface and a posterior surface, a slot being formed in the distal surface extending from the anterior surface to the posterior surface, the slot including angled side walls, a stem portion extending generally transversely away from the distal surface of the tibial tray, the modular augmentation block including a proximal surface configured for contact with the distal surface of the tibial tray, a distal surface configured for contact with a prepared bone, a pair of protrusions extending from the proximal surface of the augmentation block toward the distal surface of the tibial tray and shaped to be slidably engaged within the slot of the tibial tray, the pair of protrusions being spaced apart, the augmentation block further including at least one lateral extension extending along the distal surface of the tibial tray and being configured to contact a prepared surface of an accommodating bone, one of the pair of protrusions constituting means for rotating the augmentation block relative to the tibial tray so that the extension may be positioned posterior to the stem.