Endoprosthesis device and method

That method of anchoring an endoprosthesis immovably in a medullary canal comprising:

• providing an elongated rigid load bearing stem;
• embracing said stem with an elongated elastomeric member;
• which is fluid impervious and has an internal cavity;
• securing opposite end portions of said elastomeric member to a respective end of said stem;
• inserting said stem and elastomeric member into the open end of a medullary canal;
• and
• pressuring said elastomeric member inwardly of an outer wall thereof with a fluent material introduced under pressure into said internal cavity to expand said outer wall of the elastomeric member radially outwardly into pressurized contact with a juxtaposed surface of the medullary canal and continuously maintaining the outer wall of the elastomeric member compressed in resilient pressure contact with the medullary canal surface, said elastomeric member being effective to distribute elastic pressure substantially uniformly to the surface area of the medullary canal in contact therewith and conform to irregularities present in the juxtaposed surface portion of the medullary canal while said uniformly distributed elastic pressure applied continuously by the elastomeric member to the medullary canal is effective to anchor said endoprosthesis immovably therein.

A pressurizable elastic endoprosthesis anchoring apparatus freely insertable into a medullary canal and thereafter immovably anchorable thereto comprising:

• a rigid main body including a load bearing stem supporting a head on one end thereof;
• tubular elastomeric means having at least one tubular outer wall embracing said stem with opposite end portions thereof secured to said stem in a fluid-tight manner to provide at least one closed annular cavity;
• and
• means for pressurizing said annular cavity to hold said at least one tubular outer wall pressed into resilient continuously maintained pressurized contact with the juxtaposed surface of a medullary canal to distribute elastic pressure substantially uniformly to the juxtaposed surface area of the medullary canal in contact therewith and to conform to irregularities present in said surface and to anchor said endoprosthesis immovably therein under said uniformly distributed elastic pressure continuously applied by the outer wall of said elastomeric means.