A femoral implant of a knee joint prosthesis, comprising: a femoral component including (i) an outer surface which includes a lateral condyle surface and a medial condyle surface, and (ii) a backside surface positioned opposite the outer surface that is configured to contact a bone of a patient, a sleeve component having first and second ends and a first bore at the second end which is tapered inwardly away from the second end, and a stem component including a tapered post which capable of being received in the first bore of the sleeve component, the tapered post having a bore formed therein extending along an axis, in which (i) a passageway is defined in the femoral implant along the axis from the outer surface of the femoral component to an end of the bore of the stem component, and (ii) a fastener for securing the sleeve component to the stem component when the sleeve component is positioned between the femoral component and the stem component, the fastener extending along the axis characterised in that: the femoral component has a stem post extending from the backside surface along an axis towards its free end, the stem post having an external surface which tapers inwardly towards the free end and a bore which tapers inwardly away from the free end, the sleeve component has an outside surface provided by a plurality of step surfaces, and a second bore at the first end which is tapered inwardly away from the first end and in which the stem post is received to secure the sleeve component to the femoral component, and the tapered post on the stem component is capable of being received in the inwardly tapered bore in the stem post of the femoral component when the sleeve component is not positioned between the femoral component and the stem component. a femoral component including (i) an outer surface which includes a lateral condyle surface and a medial condyle surface, and (ii) a backside surface positioned opposite the outer surface that is configured to contact a bone of a patient, a sleeve component having first and second ends and a first bore at the second end which is tapered inwardly away from the second end, and a stem component including a tapered post which capable of being received in the first bore of the sleeve component, the tapered post having a bore formed therein extending along an axis, in which (i) a passageway is defined in the femoral implant along the axis from the outer surface of the femoral component to an end of the bore of the stem component, and (ii) a fastener for securing the sleeve component to the stem component when the sleeve component is positioned between the femoral component and the stem component, the fastener extending along the axis characterised in that: the femoral component has a stem post extending from the backside surface along an axis towards its free end, the stem post having an external surface which tapers inwardly towards the free end and a bore which tapers inwardly away from the free end, the sleeve component has an outside surface provided by a plurality of step surfaces, and a second bore at the first end which is tapered inwardly away from the first end and in which the stem post is received to secure the sleeve component to the femoral component, and the tapered post on the stem component is capable of being received in the inwardly tapered bore in the stem post of the femoral component when the sleeve component is not positioned between the femoral component and the stem component. the femoral component has a stem post extending from the backside surface along an axis towards its free end, the stem post having an external surface which tapers inwardly towards the free end and a bore which tapers inwardly away from the free end, the sleeve component has an outside surface provided by a plurality of step surfaces, and a second bore at the first end which is tapered inwardly away from the first end and in which the stem post is received to secure the sleeve component to the femoral component, and the tapered post on the stem component is capable of being received in the inwardly tapered bore in the stem post of the femoral component when the sleeve component is not positioned between the femoral component and the stem component.