Hip implant

A hip implant femoral component, which comprises:

• (A) a hip implant femoral component stem, wherein the stem includes a distal portion having a length, substantially throughout which two opposing substantially flat faces blend into two opposing convexly rounded faces;
• a proximal end;
• a stem trunnion projecting from the proximal end, which has a self-holding taper and a top, and which projects from and in a direction substantially coaxial with the distal portion;
• a hole in the stem trunnion tapped with screw threads, with the hole having an opening in the top of and substantially coaxial with the stem trunnion;
• and a rounded tip—wherein the stem and the stem trunnion together are of one piece;
• wherein:
• the flat faces are a in form of a truncated slight V-shape when viewed generally perpendicular to the rounded faces and have greater distance between them by a shoulder than by by the rounded tip, and the flat faces have less distance between them about the proximal end and substantially along the length of the stem than the rounded faces correspondingly have between them;
• and
• the stem tapers from the proximal end to the rounded tip;
• (B) a neck attached to the stem trunnion of the stem, with the neck including an associated generally curved mass having a distal base, an upper pinched cervix, two opposing substantially parallel flat faces that blend into opposing flattened curved faces, lower and upper, with the lower flattened curved face curving concavely between the distal base and the upper pinched cervix when viewed perpendicular to the two flat faces of the neck, and an upper flattened curved face curving convexly between the distal base and the upper pinched cervix when viewed perpendicular to the two flat faces of the neck;
• a neck trunnion projecting from and in a direction substantially coaxial with the pinched cervix, which has a self-holding taper that is useful for holding a hip ball head with a corresponding self-holding tapered receptacle;
• a lower female receptacle opening with respect to the distal base, which has a self-holding taper for receiving the male stem trunnion of the stem;
• at least one upper access opening to the receptacle of neck;
• and the neck and the neck trunnion together are of one piece;
• and
• (C) a securing screw threaded into the hole in the stem trunnion of the stem—wherein the securing screw is of one piece.

A kit comprising:

• (A) a hip implant femoral component stem made with a nonmagnetic cobalt-chromium-molybdenum alloy, which exhibits high strength, wear and corrosion resistance, as a wrought powder metallurgy product, is formed from a cobalt-chromium-molybdenum alloy powder having a composition type analysis in weight percent of about the following:
• Carbon, 0.20%-0.30%;
• Chromium, 26.00%-30.00%;
• Molybdenum, 5.00%-7.00%;
• Nitrogen, 0.15%-0.20%;
• Cobalt, balance−and is substantially 100% dense, wherein the stem includes:
• a distal portion;
• and
• a stem trunnion having a self-holding taper and a top, which projects from and in a direction substantially coaxial with the distal portion—
• wherein the stem and the stem trunnion together are of one piece;
• (B) a neck that can be attached to the stem trunnion of the stem and also made of a nonmagnetic cobalt-chromium-molybdenum alloy, which exhibits high strength, wear and corrosion resistance, as a wrought powder metallurgy product, formed from a cobalt-chromium-molybdenum alloy powder having a composition type analysis in weight percent of about the following:
• Carbon, 0.20%-0.30%;
• Chromium, 26.00%-30.00%;
• Molybdenum, 5.00%-7.00%;
• Nitrogen, 0.15%-0.20%;
• Cobalt, balance−and is substantially 100% dense, wherein:
• the neck includes an associated generally curved mass having a distal base, an upper pinched cervix, a lower curved face curving concavely with respect to and between the distal base and the upper pinched cervix, and an upper curved face curving convexly with respect to and between the distal base and the upper pinched cervix;
• a lower female receptacle opening with respect to the distal base, which has a self-holding taper for receiving the trunnion of the stem;
• and a ball-mating, neck trunnion projecting from and in a direction substantially coaxial with the pinched cervix, which has a self-holding taper that is useful for holding a hip ball head with a corresponding self-holding tapered receptacle;
• and
• the neck and the neck trunnion together are of one piece;
• and
• (C) the hip ball head with the self-holding tapered receptacle.

A hip implant femoral component, which comprises a hip implant femoral component neck, which is attachable to a hip implant femoral component stem, wherein:

• the stem includes a distal portion having a length and a tip;
• a proximal end;
• a stem trunnion projecting from the proximal end, which has a self-holding taper and a top;
• and
• the neck includes an associated generally curved mass having a distal base, an upper pinched cervix, a lower curved face curving concavely with respect to said mass from the distal base to the upper pinched cervix, and an upper curved face curving convexly with respect to said mass from the distal base to the upper pinched cervix;
• a lower female receptacle opening with respect to the distal base, which has a self-holding taper for receiving the trunnion of the stem;
• and a ball-mating, neck trunnion projecting from and in a direction substantially coaxial with the pinched cervix, which has a self-holding taper that is useful for holding a hip ball head with a corresponding self-holding tapered receptacle;
• and the neck and the neck trunnion together are of one piece.