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 set of instruments and a surgical technique facilitate precise orientation of the femoral implant. Precision is aided by decoupling the determination of A/P placement, valgus angle, and external rotation into three discrete steps. In this way, a surgeon's full concentration can be directed to each element of placement and fine adjustments can readily be made to each. An Epicondylar Guide is configured to ease referencing external rotation from the epicondyles. The narrow elongated guide is easily alignable with the epicondyles when it is placed on the flat distal cut. A Posterior Reference/Rotation Guide can be attached to the Epicondylar Guide to check the rotation relative to the intact posterior condyles to confirm the epicondylar setting. A slot in the guide guides a saw blade to cut a corresponding slot in the distal femur. An A/P Cutting Guide has a fin that fits in the slot cut in the distal femur.

Abstract: A package includes a cavity having a series of cavity slots transverse to the cavity's longitudinal axis. These slots permit a pair of stop plugs to be positioned to receive products of different lengths. Each stop plug has four lateral lugs for engaging the cavity slots to resist linear and rotational displacement of the stop plug. Each plug has bottom, end, and side walls to isolate the product end from the cavity. In addition a pair of fingers extending from the stop plug elastically grips the product to further restrain product movement. The fingers can flex to accommodate different sizes of products. A retainer snaps onto the cavity to close it. The retainer includes a retainer stop at each end that extends into the cavity and prevents the retainer from shifting even if the retainer is lifted due to product pressure against the retainer during shipping. The retainer also includes a pair of product restraints extending into the cavity to limit motion of the product toward the retainer.

Abstract: An improved suture anchor driver includes a handle and an extending elongated shaft adapted for passing through arthroscopic portals. The distal end of the shaft engages the suture anchor. The shaft is cannulated to allow passage of a suture from the anchor to the handle. The shaft also has a slot in its wall and extending along most of its length in communication with the interior of the shaft. The handle has a grooved knob and adjacent resilient cap for retaining a needle. A sliding member is positioned on the shaft adjacent the needle. The intermediate portion of the suture is looped through an elastic hole in order to maintain it in tension. In use, the anchor is driven into tissue. As the driver is withdrawn, the suture pulls out of the elastic hole and through the shaft. The suture then pulls the needle from the groove. A portion of the needle slides in the slot as the needle travels along the cannula. The sliding member is pulled along by the needle.

Abstract: A saw blade has two portions that are adjustable relative to one another in order to vary the overall length of the saw blade. A hub portion includes a hub adapted to engage a saw. Opposite the hub is an engagement end. A blade portion carries cutting teeth. Opposite the teeth is an engagement end. The engagement end of the blade portion engages the engagement end of the hub portion. The engagement ends carry a releasable lock to hold them in engagement to form a saw blade of a particular length. To change the saw blade length, the lock is released, the engagement ends moved relative to one another, and the lock reengaged. A locking sleeve can be slid to enclose the engagement portions to more securely hold them in engagement.

Abstract: An implant fixation stem has a distal portion with a controlled stiffness. In one embodiment the deflection in response to a given force is equal to other similarly designed stems to give a surgeon consistent implantation feedback regardless of implant size. The deflection is preferably provided via a slot in the stem, the slot length being determined as a function of the stem's moment of inertia. Alternate embodiments provide for flutes of unequal length.

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: An articular component has a fibrous structure wherein the fibers are oriented normal to the articular surface. Wear debris reduction is attributed to the increased strength of fibers over bulk material and to the abrasion resistance associated with abrading a fiber bundle on the fiber tips. This is similar to the abrasion resistance seen in a household broom which is subjected to abrasion across the tips of the broom bristles. Reduced cold flow is attributed to the increased strength and stiffness of fibers over bulk material.

Abstract: A suction adapter couples a fluid drain tube to a suction canister for fluid collection while maintaining the drain tube at atmospheric pressure for optimal draining flow rate. The suction adapter further allows the surgeon to easily apply suction to the drain tube when he desires to increase the flow rate through the drain tube and to just as easily return the drain tube to atmospheric pressure. The suction adapter does not spill and is muffled to reduce noise. The suction adapter comprises a housing defining an interior space. The housing has a suction port in communication with the interior space for connection to a suction source and a fluid port in communication with the interior space for connection to a fluid drain tube. The housing also has a ventilation port formed in the housing to allow atmospheric air into the interior space. The ventilation port communicates with a ventilation tube located in the interior space, the ventilation tube having a ventilation hole.

Abstract: A coding scheme associates multiple codes with one or more of the components of a prosthetic implant system in order to indicate the compatibility among the mating components. It is thus possible for operating room personnel to quickly and accurately select components and verify their compatibility.

Abstract: A suture anchor comprises a shaft having a proximal and a distal end. A screw thread extends from the shaft and spirals from the proximal to the distal end. A cross-hole is formed through the shaft and the screw thread near the proximal end. The cross-hole receives a suture which provides a double end of suture to facilitate attachment of soft tissue. In a preferred embodiment, the shaft is tapered from a larger diameter proximally to a smaller diameter distally while the major diameter of the screw thread remains constant over most of its length. The suture anchor contains a driven portion which preferably contains a groove to conduct the suture from the cross-hole to the free end of the driven portion. A driver for the suture anchor having an engagement portion for engaging the driven portion likewise contains a groove so that when the engagement portion engages the driven portion the two grooves align to form an enclosed passageway for conducting the suture as the suture traverses the driven portion.

Abstract: An implant comprises a plastic body and a metallic, porous surface securely fixed to the body. The porous surface is attached to the body by infiltration of the body into the porous surface such that the body and porous surface interdigitate. A filler material is embedded in the porous surface to prevent total filling of the porous surface by the body.

Abstract: A tibial knee component includes reference marks to which a surgeon can reference the location of the point of contact between the tibial component and a femoral knee component. In one embodiment of the invention, the femoral component also includes reference marks to aid the surgeon in determining the contact point and to aid in orienting the knee in specific predetermined degrees of flexion.

Abstract: An augment for an orthopaedic implant contains a countersunk through hole. A fixation means interacts with the countersink to produce both downward and lateral forces on the augment. As the fixation means is tightened, it abuts one side of the countersink so that it exerts both a downward force and a lateral force on the augment. The lateral force causes the augment to press tightly against the implant. Because of the combination of downward and lateral forces, the augment strongly resists displacement and rotation.

Abstract: A bone cement composition has adjustable rheological properties, high strength, and produces a uniform radiological image. The cement is characterized by controlled retention and release of additives incorporated in beads included in the dry component of the cement. The cement comprises beads containing a polymerization initiator in controllable concentrations from 0% to 5% or more by weight. These same beads or others may also contain an opacifier. The polymerization initiator and the opacifier may be selectively distributed throughout the beads or at specific radial locations in the beads. They may also be selectively placed in beads of a particular advantageous size range. Furthermore, in other embodiments of the invention, other advantageous additives can be incorporated in the beads such as dyes, antibiotics, bone growth factors, and other pharmacological or therapeutic agents.

Abstract: A hay feeder comprising a container for holding hay and having an open top to provide access to the hay. A wire mesh float rests on top of the hay. As hay is removed from the container the float moves down with the diminishing level of the hay. The wire mesh float allows a feeding animal to reach the hay but prevents the animal from rooting in the hay. In a preferred embodiment, the feeder includes a hinged bottom through which hay can be loaded. An extensible handle provides leverage for flipping the feeder over.

Abstract: An implant fixation stem has a distal portion with a controlled stiffness. In one embodiment the deflection in response to a given force is equal to other similarly designed stems to give a surgeon consistent implantation feedback regardless of implant size. The deflection is preferably provided via a slot in the stem, the slot length being determined as a function of the stem's moment of inertia. Alternate embodiments provide for flutes of unequal length.