A tibial prosthesis system comprising: a first tibial base plate (100) comprising: a first proximal surface (111)； a first distal surface (134) opposite the first proximal surface, the first distal surface sized and shaped to substantially cover a resected surface proximal to a tibia； a first face (160) medial； a first lateral face (162) opposite the first medial face； a first total width measured from the first medial face to the first lateral face； and a first keel (130) extending distally from the first distal surface, the first keel separated from the first medial face by a first medial distance (164) and separated from the first lateral face by a first lateral distance (166)； characterized in that the tibial prosthesis system further comprises a second tibial base plate comprising: a second proximal surface； a second distal surface opposite the second proximal surface, the second distal surface sized and shaped to substantially cover a resected surface proximal to a tibia； a second medial face； a second lateral face opposite the second medial face； a second total width measured between the second medial face and the second lateral face, the second total width that differs from the first total width whereby the first and second tibial base plates comprise unique nominal sizes； and a second keel that extends distally from the second distal surface, the second keel separated from the second medial face by a second medial distance and separated from the second lateral face by a second lateral distance, a first ratio of the first medial distance to the first total width that differs from a second ratio of the second medial distance to the second total width.Un sistema de prótesis tibial que comprende: una primera placa de base (100) tibial que comprende: una primera superficie (111) proximal； una primera superficie (134) distal opuesta a la primera superficie proximal, la primera superficie distal dimensionada y conformada para cubrir sustancialmente una superficie
