Femoral hip prosthesis

A femoral hip joint prosthesis comprising:

• a slender stem core (17) having a proximal end section for engaging a trochanteric region (14) of a femur and having a distal section (12) for extending into a medullary cavity;
• a plurality of longitudinal ribs (15) projecting from said stem core and extending along said proximal end section on each of dorsal and ventral sides of said stem core, each of said ribs having a ridge surface (18) opposite said stem core to engage surrounding bony tissues, each of said ribs having a broad surface extending between said stem core and said ridge and facing a medial side of said femur;
• each of said ribs defining a multiplicity of perforations (20) extending through said broad surface;
• and
• at least one of said ribs defining a plurality of slits, each said slit extending from said ridge surface to one of said perforations.

A femoral hip joint prosthesis for anchoring free of cement in a femur, comprising:

• a stem core (17) having a proximal end section for engaging a trochanteric region (14) of a femur (1) and having a distal section (12) for extending into a medullary cavity;
• and
• a plurality of longitudinal ribs (15) projecting from said stem core and extending along said proximal end section on each of dorsal and ventral sides of said stem core, each of said ribs having a ridge surface (18) opposite said stem core to engage surrounding bony tissue, each of said ribs having a broad surface extending between said stem core and said ridge and facing a medial side of said femur;
• said broad surfaces of adjacent ribs facing each other defining an interspace and being adapted to engage the bone tissue contained in such interspace for the transmittance of medially directed forces.