A tibial prosthesis including a tibial component including a tray having first and second opposing surfaces and a stem extending from the second surface of the tibial component, a tibial conversion module including a receiver portion defining a stem-receiving cavity for slideable engagement with the stem of the tibial component, wherein the stem of the tibial component is positioned within the stem-receiving cavity at a first end of the receiver portion, and an extension peg engaged with the stem-receiving cavity at a second end of the receiver portion that is opposite the first end of the receiver portion.