Abstract: A stem (100) for use in a joint prosthesis, such as a femoral stem for a hip joint prosthesis, the stem comprising: a solid central core (102); a proximal outer layer (127) disposed over a proximal portion (101a) of the central core, wherein the proximal outer layer comprises a set of longitudinal ribs (120), defining slots (130) there between; and a distal outer layer made of a deformable porous material disposed over a distal portion (101b) of the central core. The arrangement is such that the stem (100) can be made with a relatively large diameter yet without being excessively stiff, for cementless fixation in osteoporotic patients. The deformability of the distal outer layer also mitigates against the risk of intraoperative bone fractures.