Patent ID: 8425618

Claim:
In a human hip replacement method, the steps that include: a) providing a selected size generally vertically extending stem and laterally angled neck, the stem received into a recess in an elongated femur, the neck adapted to support a ball, b) a size selected first base carrying the neck, the base and stem having a non-circular tongue and groove interfit connection to resist relative rotary displacement therebetween, c) fitting a selected ball on an open end of said neck, d) there being an acetabular cup and insert socket being placed into an acetabulum, e) fitting said ball in the socket on a hip bone, to pivot in the socket, said selection of stem and neck, and tongue and groove connection between the size selected base and stem, enabling accurate pivoting of the ball in the socket, f) said neck extending upwardly and angularly relative to an upper horizontal surface of the base, and the base has a lower horizontal surface receivable by the stem, the upper and lower horizontal surfaces having selected vertical spacing therebetween, g) the base having front and rear endwise horizontally spaced end surfaces with selected spacing therebetween, the neck extending frontally and upwardly and above front to rear endwise spaced surfaces, said spacing between the front to rear endwise spaced surfaces selected for best fit of the ball into the socket, h) providing a second base characterized in that said first and second bases each have like sized front and rear upright substantially parallel endwise spaced end surfaces, and opposite side surfaces which are substantially parallel, the second base being endwise longer than the first base between respective end surfaces thereof, the second base also supporting a ball carrying neck sized the same as the first base neck, said step e) fitting of the ball in the socket facilitated by selectively employing one of the first and second bases for reception into a stem formed pocket, which is open ended to receive said bases.