Femoral head remodeling and prosthetic means therefor

Abstract

A femoral hip joint replacement comprises a hollow metal cap, approximating the normal femoral head size, secured to a tri-flanged insert adapted to be located within the femoral shaft and between remaining upstanding portions of the remodeled femoral head. The cap is secured to or integral with the upper surface of the insert head and rests upon the superior portion of the remodeled femoral head which has been cut downwardly at an angle of approximately 23 degrees in relation to a plane normal to the vertical axis of the femoral shaft. The sides and end of the femoral head are also resected to provide flat faces, and the upper surface of the remodeled femoral head also preferably angles upwardly front-to-back at an angle of approximately seven degrees, these angles imparting superior load-bearing characteristics to the structure in operation. The insert neck is seated on the inner surface of the cortex of the medial portion of the remodeled femur at the calcar or inferior femoral neck, and the metal shell has inner mating faces corresponding to the faces of the remodeled femoral head to facilitate close engagement therewith and securement thereto. The inner portion of the metal shell and the insert are preferably porous-coated to allow direct ingrowth of bone. Following placement of the prosthetic insert within the femoral shaft, the surgeon has the option of further securing or not securing the insert with cement.