An arrangement for the preparation of the proximal surface of the tibia for a tibial component of a prosthetic knee joint including a tibial and femoral stability gap preparation plate having a plurality of user operable height adjustable extension tabs that define a stability gap. A stability gap guide drill plate adapted to act as a guide for a drill bit to drill a series of bore holes into the proximal surface of the tibia to a depth commensurate with the height adjustment of the user operable height adjustable extension tabs and a stability gap router plate adapted to allow a router to complete a final bone resection on the surface of the tibia to rout or cut away bone about each of the series of bore holes so as to provide a stable balanced complete angular movement between a tibial component and a femoral component of the prosthetic knee joint throughout an arc of motion from extension mid flexion and flexion.
