Abstract: An improved metallic bone prosthesis having a porous coating for bone ingrowth or interlocking with bone cement is disclosed. The porous coating comprises two layers of generally ball-shaped metallic particles bonded together at their points of contact, e.g. by sintering, and defining between them a plurality of connected interstitial pores having an average pore size of from about 350 microns to about 500 microns. A high resistance to failure at the coating-substrate and bone-coating (or cement-coating) interfaces is achieved with the use of the improved prosthesis. Also disclosed are a novel method for affixing the porous coating to a metal susbstrate, and a knee joint prosthesis having bearing portions designed so that the function of said prosthesis closely approximates that of the natural knee.
Abstract: A tool for use in preparing a distal femur for the implantation of a prosthetic knee includes a central section having at least one handle. A positioning pin extends outwardly from the central section. A distal femoral condyles cutting jig is selectively connected to the central section.
Abstract: A system for electronically monitoring and controlling the drainage of fluids from a body cavity, including transducers for measuring suction, suction air flow, patient air flow, patient negativity and the like, and displays for rendering measured values in legible form. Various valves for regulating pressure and flow rates are electronically controlled according to desired values and direct measurements of the respective parameters.
Abstract: A surgical stapler includes a supply of staples which are fed one at a time to the discharge opening where a driver in the stapler housing bends the staple around the anvil, the anvil being retracted within the housing away from the discharge opening as the driver completes the bending operation.
Abstract: A device for removing fluids from a wound includes a housing and a resilient bellows inside the housing. The bellows can be collapsed and retained in a collapsed or activated state. Upon release from its activated state, the bellows is expanded so as to create a negative pressure therein whereupon fluids are automatically drawn into and collected within the bellows. Preferably the bellows is expanded by a variable force ribbon spring so that the resultant or combined restoring force provided by the resilient bellows and the variable force ribbon spring allows for the creation of a substantially constant level of negative pressure within the bellows so as to provide for a substantially constant level of suction of the device throughout the range of evacuation of fluids therein. The housing is preferably transparent with graduations provided thereon permitting the visible inspection and measurement of the fluids collected therein. A method for operating the device is also disclosed.
Abstract: A device for storing and dispensing a suture includes an outer envelope formed of two panel layers which are sealed along their peripheries so as to hermetically enclose a region therebetween. An inner container positioned within the region includes a rectangular center panel which has a pocket formed by an overlaying window to snugly retain a needle therein. A second panel foldably secured to one longitudinal edge of the center panel receives on its left-half the major portion of the suture. The right-half of the side panel is then folded over the suture and again is folded over onto the upper surface of the center panel. A tab formed of the center panel is provided so as to lock the side panel when positioned on the center panel. A window is provided in the upper panel layer and overlies the window of the center panel so that the needle and a portion of the thread are viewable therethrough.
Abstract: A femoral rasp for preparing an intramedullary canal for receiving the stem of a femoral hip prosthesis comprises a body section generally divided into a wide proximal portion and a substantially longer narrow distal portion. The body section has a shape that generally corresponds to the stem of a femoral hip prosthesis to be inserted into the prepared cavity. A plurality of spaced apart cutting teeth are located on selected portions of the outside surface of the body section for removing cancellous tissue and bone. A smooth surface on the lateral face of the body section at the free end of the distal portion prevents violation of the lateral cortex upon insertion of the body section into the intramedullary canal. Removal of the body section and insertion of the hip prosthesis results in a glove fit between the stem of the prosthesis and the cavity formed by the femoral rasp.
Abstract: An acetabulum sizer and drill guide for use in implanting an acetabular cup prosthesis comprises a substantially hemispherical shell having an outside surface that generally conforms to the outside surface of the prosthesis to be fitted into a prepared acetabulum. Viewing ports in the shell enable visual inspection of the acetabulum during sizing thereof. A circular peripheral rim on the shell is generally flush with the peripheral boundary of a properly sized acetabulum when the shell is seated therein. Drill guide structure on the shell functions to guide a drill bit into the pelvis bone adjacent the acetabulum in preparing the acetabulum for the acetabular cup prosthesis. A handle is releasably connected to the drill guide structure for manipulating the shell during sizing and drilling.
Abstract: An external wound dressing comprising a first layer of backing sheet material coated on one face with biocompatible adhesive; a second layer of protective sheet material covering the first layer in releasable contact with the adhesive, the second layer having means for separation in one or more sections from the first layer; and release-retarding means along one or a pair of opposed edges of the dressing to require a greater force to separate the layers at the edge or edges than at the remainder of the contact area.
Abstract: A prosthetic nail for stabilizing fractures in a humer has an elongated slightly twisted shape and tapers substantially over its entire length from a relatively thick head to a relatively thin tip. The elevational configuration of the nail has a thin elongated generally twisted midportion with two curved ends, a larger head end and a thinner tip end. The plan configuration of the nail tapers from the head to a blunt rounded tip. Two holes for retaining screws are provided through the head end either at right angles to the elevational length of the nail or at a slight inward inclination thereto. The retaining screws have a broad shank and are threaded for retention in the bone.
Abstract: An improved biocompatible and hemocompatible segmented poly-(ether-urethane-urea) is prepared by a process which comprises condensing an alkylene polyether diol of molecular weight of 500 to 6000 with substantially two equivalents of an aryl, aralkyl, or alkyl diisocyanate of 6 to 20 carbon atoms; condensing the thus-formed .alpha.,.OMEGA.-diisocyanato poly-(ether-urethane) with a substantially equivalent proportion of a primary alkyl diamine of 2 to 6 carbon atoms until a degree of condensation of about 5 to 20 is achieved; condensing the resulting poly-(ether-urethane-urea) with a primary alkyl amine or diamine of up to 6 carbon atoms in an amount substantially equivalent to the free isocyanate content of the poly-(ether-urethane-urea); and condensing the amine-treated poly-(ether-urethane-urea) with an amine-reacting agent in an amount substantially equivalent to the free amine content of the amine-treated poly-(ether-urethane-urea).
Abstract: A novel cannula is disclosed for use in the application of bone cement to the prepared intramedullary canal of a bone prior to the cementation of a surgical implant therein. The novel cannula comprises a hollow tube adapted to slidingly receive the nozzle of a bone cement extruder, an inflatable cuff surrounding the tube, and means to inflate the cuff. In operation, the inflated cuff forms a seal against the wall of the intramedullary canal, thereby preventing escape of cement through the open end of the prepared canal and insuring that the applied cement is properly pressurized within the canal. As a result, a highly secure cementation of the surgical implant within the intramedullary canal is achieved.
Abstract: An extractor for dislodging an implanted tibial prosthesis comprising substantially parallel upper and lower members joined by a yoke, with the lower member comprising a pair of forked blades to insert under the tibial component and the upper member being adapted to receive means for applying upward dislodging force.