| 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 ( 101 a ) 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 ( 101 b ) 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. |