A modular knee prosthesis system includes a femoral component having a stem and a sleeve. The system is modular, and provides the surgeon with the option of distally offsetting the joint line by controlling the relative axial positions of the stem and the sleeve. Alternative options include providing sleeves with tapered bores of different diameters, thereby providing a shim to be placed between the sleeve; and the stem and providing the stems as adapters having different diameters.