Abstract: An orthopedic component having multiple layers that are selected to provide an overall modulus that is substantially lower than the modulus of known orthopedic components to more closely approximate the modulus of the bone into which the orthopedic component is implanted. In one exemplary embodiment, the orthopedic component is an acetabular shell. For example, the acetabular shell may include an outer layer configured for securement to the natural acetabulum of a patient and an inner layer configured to receive an acetabular liner. The head of a femoral prosthesis articulates against the acetabular liner to replicate the function of a natural hip joint. Alternatively, the inner layer of the acetabular shell may act as an integral acetabular liner against which the head of the femoral prosthesis articulates.

Abstract: A metal-backed acetabular implant and a method of forming the same.

Abstract: An orthopedic component having multiple layers that are selected to provide an overall modulus that is substantially lower than the modulus of known orthopedic components to more closely approximate the modulus of the bone into which the orthopedic component is implanted. In one exemplary embodiment, the orthopedic component is an acetabular shell. For example, the acetabular shell may include an outer layer configured for securement to the natural acetabulum of a patient and an inner layer configured to receive an acetabular liner. The head of a femoral prosthesis articulates against the acetabular liner to replicate the function of a natural hip joint. Alternatively, the inner layer of the acetabular shell may act as an integral acetabular liner against which the head of the femoral prosthesis articulates.

Abstract: A metal-backed acetabular implant and a method of forming the same.

Abstract: A method and apparatus for mixing bone cement which produces bone cement essentially free of entrained air. The apparatus includes a cartridge having two telescoping cylinders. The outer cylinder receives a cap thereon which hermetically seals the cartridge. The cap includes an outlet port in which a break-away agitator is installed and a port for connection of a vacuum pump. In use, a desired vacuum pressure is drawn on the cartridge and the inner cylinder is allowed to be drawn into the outer cylinder while the vacuum is being drawn, whereupon the inner cylinder automatically stops moving relative to the outer cylinder when the desired vacuum pressure is reached. Mixing of the bone cement is then performed under the partial vacuum thereby created. The agitator paddles provide a scraping action against both inner cylinder walls of the telescoping cylinders thereby improving mixing.

Abstract: A paste injector gun, especially adapted for injecting bone cement, has first and second mechanical advantages. In a first embodiment, the first and second mechanical advantages are produced by two fulcrums engageable during different portions of the trigger stroke. In a second embodiment, the first and second mechanical advantages are produced by a fixed fulcrum and a rotatable fulcrum. The first mechanical advantage is greater than the second such that the first facilitates pressurizing the bone cement and the second facilitates high volume dispensing of the bone cement. The injector gun also includes a pair of U-shaped slots. One of the slots is sized to accept a large cement cartridge and the other slot is sized to accept a small cement cartridge. An alternative embodiment provides a hinged cartridge retaining gate for closing the U-shaped slots for positive retention of the cartridge.

Abstract: A paste injector gun, especially adapted for injecting bone cement, has first and second mechanical advantages corresponding to different portions of the trigger stroke. The first mechanical advantage is greater than the second such that the first facilitates pressurizing the bone cement and the second facilitates high volume dispensing of the bone cement. The injector gun also includes a pair of U-shaped slots. One of the slots is sized to accept a large cement cartridge and the other slot is sized to accept a small cement cartridge.

Abstract: A preassembled collection of disposable mixing apparatus and constituent components needed for the vacuum mixing and preparation of bone cement and packaged as a single disposable kit is disclosed. The kit includes a contoured storage tray, ampules of liquid cement monomer, packets of powder cement copolymer, a small portable vacuum pump, connecting tubing with a vacuum indicator, a mixing cartridge, a cartridge cap and agitator, an assortment of connectable cement nozzles, and a funnel attachment. The kit can be packaged as a single unit for convenient and efficient use in the sterile environment of an operating room. The disposable telescoping mixing cartridge of the kit employs a telescoping mixing cartridge with a vacuum release mechanism.

Abstract: In a syringe assembly comprising an outer barrel for a powder medicament, an inner barrel telescopically mounted in the outer barrel for diluent, seal means isolating the powder and diluent compartments comprising a plug member made of a resilient material sealingly engaging in the discharge opening of the inner barrel, plunger means mounted on the discharge end of the inner barrel including a hollow plug chamber closed at one end remote from the discharge end of the inner barrel by a wall having a plurality of discharge openings therein, said plug adapted upon pressure buildup in the inner barrel to be displaced axially outwardly into said plug chamber to permit flow of diluent from the inner barrel to the powder compartment.