US 4,697,584 AGranted

Device and method for plugging an intramedullary bone canal

AssigneeDarrel W. Haynes

InventorDarrel W. Haynes

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Abstract

This invention relates to a method of plugging the open end of an intramedullary bone canal with an inflatable bone plug which is capable of restricting the flow of bone cement during the insertion of bone cement, particularly during the pressurized injection of such a cement, during an operative procedure involving the fixation of the stem of an artificial joint prosthesis to the end of a bone such as in the fixation of a hip joint prosthesis to the proximal femur. The inflatable bone plug is inflated with a fluid which is capable of escaping from the plug within a relatively short period of time after the bone cement holding the prosthesis in place has hardened to avoid possible weaking of the cortical bone surrounding the inflated plug. This invention also relates to an inflatable bone plug of the above type which is preferably constructed from a silicone elastomer and is pressurized with carbon dioxide gas.

Claims20

Dependent claims

A method of replacing a diseased or damaged joint with a prosthetic device of the type including a stem fixable within the intramedullary bone canal of an open-ended bone adjacent to the joint, said method comprising the steps of:

(A) preparing the end of the bone and the intramedullary canal of the bone for receipt of the stem of an artificial joint prosthesis,
(B) inserting an inflatable bone plug into the canal a distance from the open end of said bone which is at least more than the distance which the stem will be inserted into said canal for cementing to the bone, said plug comprising an expandable container of a biocompatible elastomeric material having an exterior wall configuration which is adapted to be received within said canal and an interior wall enclosing a hollow interior region, said container having a first end fitted with a reealable valve means to enable injection of a biocompatible fluid into said hollow interior means through the use of a further cooperating injection means which is sealingly enageable with said valve means and an opposing second end, said second end being the end which is first inserted into the open end of said canal, said container wall having a sufficient strength and thickness to contain pressure resulting form injection of said fluid, said container further containing a means for the controlled release of said fluid to reduce the pressure therein to a minimum within a preselected amount of time after injection of a pressuring amount of said fluid,
(C) injecting a preselected quantity of fluid into said interior region through the use of the injection means to raise the pressure of said interior region to a sufficient level to enable the outside wall of the container to sealingly conform to the walls of the intramedullary bone canal surrounding the container,
(D) removing the injection means,
(E) inserting a hardenable bone cement material and said stem into said canal, wherein the cement is prevented from flowing beyond said plug as a result of the contact with the canal produced by the pressure of the fluid within said interior region,
(F) allowing the cement to harden, and
(G) allowing the pressure within said container to drop to a minimum after the cement has hardened.

4 more elements

An inflatable implantable bone plug for plugging an open-ended intramedullary canal of a bone to restrict the flow past said plug of a hardenable bone cement used to fix the stem of an artificial joint prosthesis into the open end of said canal, said plug comprising an expandable container of a biocompatible elastomeric material having an exterior wall configuration which is adapted to be received and implanted within said canal between said stem and the remainder of said intramedullary canal, said outside wall being configured to sealingly conform to the walls of said canal surrounding the container when the container is pressurized to prevent bone cement from passing beyond the plug and entering the remainer of said intramedullary canal, said container having an interior wall enclosing a hollow region, said container having a first end fitted with a resealable valve means to enable injection of a biocompatible fluid into said interior region through the use of a further cooperating and removable injection means which is sealingly engageable with said valve means and which injection means is removed from said valve means before the insertion of said cement and said stem within the open end of said canal and an opposing second end, said second end being the end which is first inserted into the open end of said canal, said container walls having a sufficient strength and thickness to contain pressure from injection of said fluid, said container further containing a means for the controlled release of said fluid into the remainder of said intramedullary canal to reduce the pressure within said interior region to a minimum a preselected amount of time after injection of a pressurizing amount of said fluid and thereby reduce the pressure against the walls of said intramedullary canal surrounding said plug after said cement has hardened.

Dependencies are inferred from the claim text.