Abstract: In a tibial portion of a knee joint endoprosthesis with a securing shank (10) to be inserted into the medullar cavity of the tibia, which, on one end, is provided or not with a tibia condyle terminal plate for the attachment of the articular parts of the prosthesis, the securing shank (10), in order to achieve a firm fit of the implant after the implantation, comprises a cylindrical sleeve (11) that is insertable into a cylindrical slotted drilled hole (201) of the tibia with an interior (12) accommodating the spongiosa nucleus (205) of the slotted drilled hole (201), and is fabricated from a metallic material or some other suitable, body-compatible material, while the securing shank (60) is disposed at a right angle to the terminal plate (20) extending parallelly to the horizontal or slightly inclined ostectomy area (206) (FIG. 1).

Abstract: The milling guide of this invention provides a guide having a base with a track formed therein to slidably accommodate a milling device and guide the milling device along the bone. The milling device provides a smooth bone surface and the guide is provided to maintain the milling device generally transverse to the longitudinal axis of the tibia. A slider is carried by the track and accommodates the milling device to maintain the milling device generally perpendicular relative to the guide. The slider is shiftable within the guide in an medial-lateral plane. The milling device is shiftable relative to the slider and guide in the anterior-poster plane as well.

Abstract: A comb for connection to the skin meshing unit adjacent the cutter blades to contact the blades to remove the skin from the blades. The comb includes a plurality of slots which accommodates a portion of the cutter blades as the blades rotate through the skin sample passed under the blades. Each longitudinal end of the slot includes angled side wall and is bevelled relative to the bottom wall of the comb to form a V-shaped groove which engages the cutting edge of the blades in close contact to remove the skin from the cutter.

Abstract: A cement plug received within a bone recess is extracted by forming a bore within the plug, tapping the bore to form internal screw threads therein, engaging the threads with a pulling tool, and applying tension to the tool to extract the plug. The bore is formed through means of a rod inserted into the plug while in a fluid state and/or a drill bit having a tubular guide received therearound to maintain the bit in generally aligned condition with the bone recess and limit the depth to which the bit penetrates the plug. The degree to which the bore is tapped and engaged by the pulling tool is controlled to avoid exceeding the extent of the bore and the screw threads formed therein. One embodiment employs a self-tapping extraction rod which serves both as a tap to form the screw threads and as the pulling tool to apply tension to extract the plug. Another embodiment employs a tap which is separate from the pulling tool.

Abstract: A femoral component for a knee joint prosthesis having a modular cam which may be connected intraoperatively to provide posterior tibial subluxation resistance when the posterior cruciate ligament is sacrificed. The cam includes protrusions which engage with notches on the stem base to prevent rotation of the cam during use. A stem extension is connected to the stem base for clamping engagement of the cam body therebetween. A transverse opening may be formed in the stem base for providing access to the stem extension threads. The threads may then be malformed to prevent rotation of the stem extension relative to the extension.

Abstract: The targeting device of this invention includes a radio-transparent handle and a metal snap fit barrel. The radio-transparent handle reduces obstructions in the radio-graphic image to provide a clearer image to the surgeon for proper placement of the locking screws. The metal snap fit barrel is retained in the handle by an interference fit between the handle and biased keys carried by the barrel. After use, the barrel may be easily disassembled for cleaning by striking a removal tool against the keys to drive the barrel from the handle.

Abstract: The acetabular cup assembly of this invention includes a bearing component having an elevated rim and a metal cup. A groove is formed about the component for engagement with a locking ring carried by the metal cup. The bearing component may be inserted into the cup and tilted or tipped so that the elevated rim is pressed downwardly against the rim of the metal cup. In this position, the elevated portion of the rim is out of the way of the surgeon permitting the head to be more easily inserted into the bearing component. Once the head is seated the surgeon presses against the raised lip of the bearing component to shift the bearing component such that the elevated lip is properly positioned. A snap ring locks into a groove of the bearing component when positioned for use.Accordingly, it is an obejct of the invention to provide a novel acetabular hip cup assembly.

Abstract: A prosthetic hip stem implant and torque wrench adapter. The hip stem includes an extraction bore formed through its body and a plurality of recessions formed in the body upper surface. A lip extends outwardly of the body and including alignment indicia for visually aligning the implant during seating. The torque wrench adapter includes a movable arm which is accommodated in the extraction bore of the implant. A pair of protrusions extending downwardly from the adaptor head to engage the implants' recesses. An adjustment screw shifts the arm toward the protrusions to clamp the adapter to the implant.

Abstract: A two piece bone screw having a separate head and shaft adapted for slidable engagement relative to one another. The head and shaft include a plurality of teeth which mutually engage to permit the head to shift relative to the shaft in only one direction. Therefore, under load, the head is shifted downwardly along the shaft to shorten the length of the screw in a ratcheting manner.

Abstract: The invention provides a temporary clamp for connection to the midline clamp which holds the midline clamp in engagement about the lamina and is small enough to be substantially out of the way of the surgeon in use. The temporary clamp is removably connected to the midline clamp by a pair of screws. The temporary clamp is releasably connected to a clamp inserter such that after the midline clamp and temporary clamp is connected to the vertebra, the clamp inserted may be removed and used to connect subsequent temporary clamps. Therefore, since the clamp inserter may be removed from the surgical site without releasing the midline clamp, the surgeon may connect a plurality of the midline clamps with temporary clamps attached without significantly obstructing the surgical site.

Abstract: A prosthetic implant for insertion into a cement filled intramedullary canal including a plurality of spacers formed from PMMA. The spacers include a body having a frontal portion and a trailing portion. The body of the spacers narrowing with distance from said frontal portion toward said trailing portion. The narrowing body of the spacers interrupting the flow of cement along the implant body as the body is inserted into a cement filled intramedullary canal. The narrowing trailing portion of the spacers cause the cement flow to smoothly re-attach to the implant body without creating substantial disturbances or vortexes in the cement.

Abstract: A method and apparatus for removing a pre-placed prosthetic joint from a bone cavity and conditioning the cavity for receipt of a replacement joint. The pre-placed joint is first pulled from the mantle of hardened cement holding it within the cavity, thus leaving a cavity within the mantle. A mass of fluid cement is then placed within the cement cavity, after which a pulling appliance is inserted into the fluid cement and the fluid cement is permitted to cure to bond the appliance to the mantle. Tension is then applied to the pulling appliance to remove the appliance and the cement mantle from the bone cavity as a unit. The fluid cement partially dissolves and softens the hardened cement mantle so that an integral cement mass is formed upon curing of the fluid cement. The pulling appliance is of a screw-like configuration, with means to connect a slap-hammer to its proximal end.

Abstract: Over tightening of the threaded rods used to engage and remove the cement for prosthetic joints is avoided by measuring the depth of the passages into which the rods are threaded and providing sleeves on the rods which serve as visual indicia of the extent of penetration of the rods into the cement. A depth gauge calibrated in both units of length and screw thread turns is provided for the measuring function. The sleeves are slidably received on the rods and proportioned to engage the edges of the passages into which the rods are threaded. In use, the sleeves slide toward a marker as the rods are threaded into place.

Abstract: A femoral component for a knee joint prosthesis having a modular cam which may be connected intraoperatively to provide posterior tibial subluxation resistance when the posterior cruciate ligament is sacrificed. The cam includes protrusions which engage with notches on the stem base to prevent rotation of the cam during use. A stem extension is connected to the stem base for clamping engagement of the cam body therebetween. A transverse opening may be formed in the stem base for providing access to the stem extension threads. The threads may then be malformed to prevent rotation of the stem extension relative to the extension.

Abstract: A method of making a femoral rasp wherein the hip stem implant is used to make a two part mold. The mold halves are separated and the implant removed to yield left and right mold halves representing corresponding halves of the hip stem. The cavities of the mold halves are lined with wax and a plurality of blades are imbedded into the wax such that an anchor portion of each of the blades remains exposed. The mold halves are connected together and a stem of handle is inserted therein. A moldable material such as PMMA is poured into the mold and allowed to cure. When the PMMA is hard or cured, the mold halves are separated and the wax is removed from the rasp body exposing the cutting surfaces of the teeth.

Abstract: The surgical saw blade includes a main body portion and a cover portion joined to provide an enclosed manifold space. Irrigation channels extend from the manifold space to saw teeth provided on the saw blade. In one embodiment of the invention the saw teeth are provided at an end portion of the saw blade. In another embodiment of the invention the irrigation channels extend toward saw teeth provided along the longitudinal side edge of the saw blade. In either embodiment of the invention the irrigation channels commonly communicate with the fluid manifold and are uniformly distributed among the cutting teeth to provide a uniform distribution of fluid during a cutting action. Depending upon the positioning of the saw teeth on the blade and the movement provided to the blade, one embodiment of the saw blade can be used for oscillatory cutting action and another embodiment of the saw blade can be used for reciprocating cutting action.

Abstract: A prosthetic implant for insertion into a cement filled intramedullary canal including a plurality of spacers formed from PMMA. The spacers include a body having a frontal portion and a trailing portion. The body of the spacers narrowing with distance from said frontal portion toward said trailing portion. The narrowing body of the spacers interrupting the flow of cement along the implant body as the body is inserted into a cement filled intramedullary canal. The narrowing trailing portion of the spacers cause the cement flow to smoothly re-attach to the implant body without creating substantial disturbances or vortexes in the cement.

Abstract: A drill having a variable speed trigger and logic circuit which can control the direction and speed of rotation. In an alternating mode of operation, the logic circuit alternates the direction of motor/chuck rotation on each successive activation of the trigger. The drill can also be set to rotate in either a forward or reverse direction without the alternating feature. A pair of lights provide visual confirmation that the drill is set to rotate in either a forward or reverse direction. The drill can also be set in a safe mode to prevent rotation in either direction.

Abstract: The arthroscopic surgery instrument includes an elongated outer sheath member having substantially fully open distal and proximal ends, and an inner hollow cylindrical cutting blade member rotatable within the sheath member. The cutting blade member has a distal end that is substantially fully open. The cutting blade member and the sheath member are each provided with a pair of spaced longitudinally extending, diametrically opposed tabs at their corresponding distal ends. The spaces between the tabs on the sheath member defines oppositely disposed cutting windows. Cutting edges are formed on each of the tabs on the cutting blade member and the sheath member and extend to the free ends of each member. The cutting edges on the cutting blade member are cooperable with the corresponding cutting edges on the sheath member. A rotary drive motor rotates the cutting blade member relative to the sheath member.

Abstract: A multiple spindle bar machine which includes a carrier rotatively supporting a plurality of spindles. The carrier is rotatable to index the spindles to a successive work station. Separate spindle drives supported by the carrier are provided to rotate each spindle independently of each other spindle. Each spindle drive includes a motor supported by the frame and a clutch assembly for transferring rotative motion from the motor to the drive means. Each clutch assembly includes two clutch plates which are separable to allow rotation of the carrier to index the spindles.