A femoral sizing guide comprises a body, a superstructure and a stylus. The body has feet extending underneath and resting against posterior condylar surfaces of the femur and an extension component. The superstructure is slidable on the extension component and the extension component is rotatable with respect to the feet. The stylus may be coupled to the superstructure. The superstructure has a first guide hole defining a first alignment axis and the extension component has a second guide hole defining a second alignment axis. The distance between the first and second guide holes varies as the superstructure slides relative to the body. A method of locating an alignment axis on a resected femoral surface at a distal end of a femur which is transverse to the longitudinal axis of the femur using the femoral sizing guide is also disclosed.
