A partial knee prosthesis for replacing one of a medial tibiofemoral joint of a knee and a lateral tibiofemoral joint of the knee, the prosthesis comprising: a tibial implant having an inferior surface and an opposite, superior surface, the inferior surface being configured to be fixed to a tibia of a patient; a femoral implant mateable to the tibial implant and having an inferior surface and an opposite, superior surface, the superior surface being configured to be fixed to a femur of the patient, and the tibial implant being configured to articulate relative to the femoral implant when the tibial implant is fixed to the tibia and the femoral implant is fixed to the femur; wherein, when the partial knee prosthesis is for replacing a medial tibiofemoral joint of a knee, the tibial implant has a medial compartment configured to be seated on a medial surface of the tibia with a first portion of the tibial implant being seated on or over the tibia's medial surface and a second, substantially smaller portion of the tibial implant being seated on or over the tibia's lateral surface, and a post extends from the superior surface of the tibial implant near an edge thereof, the post being configured to be substantially centered on the tibia when the tibial implant is fixed thereto such that the post simulates an anterior cruciate ligament when the tibial implant is fixed to the tibia and the femoral implant is fixed to the femur, and wherein, when the partial knee prosthesis is for replacing a lateral tibiofemoral joint of the knee, the tibial implant has a lateral compartment configured to be seated on a lateral surface of the tibia with a first portion of the tibial implant being seated on or over the tibia's lateral surface and a second, substantially smaller portion of the tibial implant being seated on or over the tibia's medial surface, and a post extends from the superior surface of the tibial implant near an edge thereof, the post being configured to be substantially centered on the tibia when the tibial implant is fixed thereto such that the post simulates an anterior cruciate ligament when the tibial implant is fixed to the tibia and the femoral implant is fixed to the femur. a tibial implant having an inferior surface and an opposite, superior surface, the inferior surface being configured to be fixed to a tibia of a patient; a femoral implant mateable to the tibial implant and having an inferior surface and an opposite, superior surface, the superior surface being configured to be fixed to a femur of the patient, and the tibial implant being configured to articulate relative to the femoral implant when the tibial implant is fixed to the tibia and the femoral implant is fixed to the femur; wherein, when the partial knee prosthesis is for replacing a medial tibiofemoral joint of a knee, the tibial implant has a medial compartment configured to be seated on a medial surface of the tibia with a first portion of the tibial implant being seated on or over the tibia's medial surface and a second, substantially smaller portion of the tibial implant being seated on or over the tibia's lateral surface, and a post extends from the superior surface of the tibial implant near an edge thereof, the post being configured to be substantially centered on the tibia when the tibial implant is fixed thereto such that the post simulates an anterior cruciate ligament when the tibial implant is fixed to the tibia and the femoral implant is fixed to the femur, and wherein, when the partial knee prosthesis is for replacing a lateral tibiofemoral joint of the knee, the tibial implant has a lateral compartment configured to be seated on a lateral surface of the tibia with a first portion of the tibial implant being seated on or over the tibia's lateral surface and a second, substantially smaller portion of the tibial implant being seated on or over the tibia's medial surface, and a post extends from the superior surface of the tibial implant near an edge thereof, the post being configured to be substantially centered on the tibia when the tibial implant is fixed thereto such that the post simulates an anterior cruciate ligament when the tibial implant is fixed to the tibia and the femoral implant is fixed to the femur.