Pressure injection of bone cement apparatus and method

A system for injecting a low viscosity pre-mixed penetrating bone cement into a bone cavity, prior to placement of a prosthetic device into the bone cavity, under sufficient pressure to cause the cement to penetrate between the trabeculae of the bone, said system comprising;

• (a) cartridge means having an opening at one end thereof and a piston at the opposite end thereof, and a low viscosity bone penetrating cement having a viscosity, at 68.degree. to 70.degree. F., of less than 2,000 poises, up to about the sixth minute after the time of initial mixing of the cement, said opening functioning as both an inlet for loading said cement into said cartridge means and as an outlet from which said cement can be forced out of said cartridge means;
• (b) extruding means for forcing a low volume of about 2 to 3 cubic centimeters of the penetrating bone cement in said cartridge means to move towards said outlet opening, said extruding means comprising
• a housing for engaging the end of the cartridge having the piston;
• pressure means for forcing the piston into the cartridge means and comprising a rod supported in said housing in axial alignment with respect to said cartridge means, one end of said rod engaging the piston and a means for slideably engaging said rod;
• and
• manual activating means for actuating the pressure means and comprising a lever pivotally connected to the housing by a pivot pin, said lever having one end manually movable with respect to the housing and having the opposed end thereof engaging the means for slideably engaging the rod;
• wherein said opposed end of the lever which engages the means for slideably engaging the rod, said pivot pin, and said lever are configured such that a single manual actuation of said lever causes said slideable engaging means to move said rod which moves said piston into the cartridge means a distance sufficient to forcibly eject said low volume of low viscosity penetrating bone cement through said outlet opening under substantial pressure sufficient to cause said cement to penetrate between the trabeculae of the bone;
• and
• (c) removable nozzle and pressure sealing means at the outlet opening of said cartridge means for applying the low volume of low viscosity penetrating bone cement forced from the cartridge means by the extruding means to the bone cavity and for providing a pressure seal between said bone cavity and said outlet opening, whereby said low volume of low viscosity penetrating bone cement will be injected into the bone cavity under said substantial pressure and will penetrate between the trabeculae of the bone to thereby provide a bone/cement interface to securely hold said prosthetic device in place,
• wherein said removable nozzle and pressure sealing means comprises a removable closure cap fitting over the outlet opening of said cartridge means and having an outlet orifice and at least one nozzle removably connectable to said outlet orifice, at least one of said nozzles having an outlet portion shaped to close against an entrance to a bone cavity to thereby provide said pressure seal between said bone cavity and said outlet opening.