Patents Assigned to Pfizer Hospital Products Group, Inc.
  • Patent number: 5658292
    Abstract: A method and apparatus for preparing a planar surface on the distal femur prior to implantation of a femoral knee prosthesis has a femoral plate with an opening therein for exposing both condyles of the femur. A guide with a central aperture is used to align the femoral plate on the distal femur. The guide is releasably secured to the femoral plate and an intramedullary guide rod is placed through the aperture therein and into the intramedullary canal of the femur. After alignment with the intramedullary canal, the femoral plate is pinned to the femur and the rod and guide are removed. A milling guide having two bores, one adjacent each condyle, is then placed on the femoral plate and an end mill is used to mill a planar surface on at least one of the condyles.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: August 19, 1997
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventor: Stuart L. Axelson, Jr.
  • Patent number: 5417695
    Abstract: A method and apparatus for preparing a planar surface on the distal femur prior to implantation of a femoral knee prosthesis has a femoral plate with an opening therein for exposing both condyles of the femur. A guide with a central aperture is used to align the femoral plate on the distal femur. The guide is releasably secured to the femoral plate and an intramedullary guide rod is placed through the aperture therein and into the intramedullary canal of the femur. After alignment with the intramedullary canal, the femoral plate is pinned to the femur and the rod and guide are removed. A milling guide having two bores, one adjacent each condyle, is then placed on the femoral plate and an end mill is used to mill a planar surface on at least one of the condyles.
    Type: Grant
    Filed: July 27, 1992
    Date of Patent: May 23, 1995
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventor: Stuart L. Axelson, Jr.
  • Patent number: 5380290
    Abstract: A device for providing access to a living body. The device, in one embodiment, includes a slotted needle dimensioned and configured to receive, in fluid tight engagement, a catheter or a guidewire introduced into the needle through the slot. The device, in another embodiment, includes a sharpened, slotted first tube, a second tube piercable by the first tube for receipt therein of at least a potion of both the first tube and the slot, and an elongated element passing into the second tube, through the slot and into the first tube. The device might further include a third tube slidably positioned around the second tube.
    Type: Grant
    Filed: April 16, 1992
    Date of Patent: January 10, 1995
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Joshua Makower, Earl H. Slee, Naomi C. Chesler, William J. Gorman, Frank E. Barber
  • Patent number: 5364398
    Abstract: A modular femoral internal implant system for use in the treatment of femoral disorders resulting from injury, disease or congenital defect includes at least three interconnectable components: 1) an elongated epiphyseal/metaphyseal implant, 2) an intramedullary rod and 3) an angled side plate having an elongated plate portion adapted to be secured to the outer cortical wall and a hollow sleeve adapted to extend into the femur. The epiphyseal/metaphyseal implant can be connected to either the angled side plate or the intramedullary rod. The system may also include an elongated bone plate connectable to the angled side plate, one or more additional epiphyseal/metaphyseal implants of variable length, an additional angled side plate, a distal buttress plate connectable to the elongated bone plate, and a plurality of bone screws of a universal design. Preferably, many or all of the components of the system are made of an inert, resilient titanium-base alloy.
    Type: Grant
    Filed: September 21, 1992
    Date of Patent: November 15, 1994
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Michael W. Chapman, Charles C. Edwards, Dana C. Mears
  • Patent number: 5276070
    Abstract: There is disclosed a bone cement composition comprising (a) a liquid component comprising a monomer of an acrylic ester and (b) a powdered component comprising a terpolymer of methyl methacrylate, butyl methacrylate, and styrene. A prepared terpolymer, based on the weight of the powdered component, has between 55 to 89.5% methyl methacrylate, 10 to 40% butyl methacrylate and 0.5 to 5% styrene.
    Type: Grant
    Filed: March 31, 1992
    Date of Patent: January 4, 1994
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventor: Nestor A. Arroyo
  • Patent number: 5266326
    Abstract: A method of modifying salts of alginic acid in situ for prevention and treatment of various intra-articular and extra-articular (spine) complications modifies the alginate in situ to an insoluble gel. This in situ modification provides a final product which can be compressed within the intra-articular space thus remaining localized. The modified material can have varied mechanical strengths and thus varied degradation times and can serve as a matrix for localizing and slowly releasing therapeutic agents. The modified material is biocompatible and biodegradable, thus requiring no reoperation for removal.
    Type: Grant
    Filed: June 30, 1992
    Date of Patent: November 30, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: James J. Barry, Paul A. Higham, Harold M. Aberman
  • Patent number: 5263985
    Abstract: An implantable material for promoting bone growth has a microporous structure exhibiting an average pore size of at least 30 .ANG.. The porous biomaterial is capable of retaining macromolecules having a molecular weight of at least 15,000 and up to 500,000.
    Type: Grant
    Filed: November 20, 1992
    Date of Patent: November 23, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Qi-Bin Bao, John H. Dumbleton, Paul A. Higham
  • Patent number: 5258420
    Abstract: A bone cement is disclosed wherein the liquid component contains a therapeutic or diagnostic substance in combination with an emulsifying agent for said substance.
    Type: Grant
    Filed: June 10, 1991
    Date of Patent: November 2, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Jessica Posey-Dowty, Paul A. Higham, Nestor A. Arroyo, Casper F. Stark
  • Patent number: 5250050
    Abstract: A modulator apparatus for use in the preparation of bone surfaces and the implantation of a modular total knee prosthesis in a patient, which apparatus comprises cutting guides, templates, alignment devices, a distractor and clamping instruments which provide modularity and facilitate bone resection and prosthesis implantation.
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: October 5, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Matthew P. Poggie, Peter S. Walker, Frederick C. Ewald
  • Patent number: 5234456
    Abstract: A stent for placement within a body lumen and comprising a wall structure wherein at least a portion thereof is a hollow wall. The hollow wall has disposed therein a hydrophilic material which can be in the form of a gel, for example, which swells upon introduction of a liquid into the hollow wall to thereby achieve inflation thereof. The hollow wall is fabricated of a semi-permeable membrane whereby fluid from tissues surrounding the stent at the site of placement can pass through the membrane and swell the hydrophilic material to thereby inflate the hollow wall. A drug can be disposed with the hydrophilic material for release through the membrane at the site of stent placement. The entire wall structure of the stent can be a hollow wall, or the wall structure can incorporate both hollow and non-hollow wall portions such as hollow and solid fibers which are braided, woven or wound together.
    Type: Grant
    Filed: May 7, 1992
    Date of Patent: August 10, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventor: Thomas A. Silvestrini
  • Patent number: 5217462
    Abstract: An implant comprising a specially adapted bone screw having a threaded shank portion and a sleeve which mates with and operates in cooperation with the threaded shank portion is provided. Also provided is a driver specially adapted for inserting and removing the implant of the invention. A method of compressing a fracture in a bone is also provided. The implant generates bone compression by itself and can be used either alone or with plates and washers. It is easily inserted into a fracture and also is easily removed from the fracture. The driver which is specially adapted to be used in combination with the implant of the invention aids in the ease of insertion and removal of the implant.
    Type: Grant
    Filed: March 5, 1991
    Date of Patent: June 8, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Stanley E. Asnis, John S. Crombie, Lewis B. Lane
  • Patent number: 5213112
    Abstract: A tension meter for measuring the degree of tension between bones has a grip portion, a tension meter body mounted to the grip portion, and a torque setting device rotatably connected through a torque shaft to the tension meter body. The tension meter body includes a body portion, a fixed arm extending from one end of the body portion, and a movable arm mounted on the body portion so as to be movable away therefrom. The movable arm is located in opposed relationship to the fixed arm. The movable arm is provided with a gear portion meshing the torque shaft. The torque setting device is provided with a torque limiter for limiting relative displacement of the movable arm in relation to the fixed arm according to a force to be applied between the fixed arm and the movable arm. Use of the tension meter produces quantitative data which makes it possible to carry out surgical operations with reproducible results because they do not rely only upon the surgeon's senses.
    Type: Grant
    Filed: January 29, 1992
    Date of Patent: May 25, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Shigeo Niwa, Mineo Sakakibara
  • Patent number: 5203653
    Abstract: A reamer for shaping a socket, such as a hip socket, comprising a cutter head located at one end of a rotatably driven shaft and having a hemispherical portion with a hemispherical exterior surface, the hemispherical portion containing a closed hollow chamber, and helical openings, such as slots, in said hemispherical portion connecting between the exterior surface and the chamber, the trailing portion of each of the openings having a cutting edge raised slightly above the hemispherical surface to move material from the socket into the chamber during rotation of the cutter head, and an attachment element for connecting and disconnecting the cutter head and the drive shaft.
    Type: Grant
    Filed: December 30, 1991
    Date of Patent: April 20, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventor: John W. Kudla
  • Patent number: 5203595
    Abstract: A coupling device and method of coupling especially suitable for coupling multiple components of surgical instruments are provided. A wedging portion provides an interference fit between parts so that a secure connection can be made that will not unintentionally dissociate. In a preferred embodiment, bores and counterbores within dovetail portions are provided. Especially preferred is the use of this coupling device to secure a reamer head to a shaft.
    Type: Grant
    Filed: February 2, 1990
    Date of Patent: April 20, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Rocco R. Borzone, Jay Bichet, Thomas F. McCarthy
  • Patent number: 5201735
    Abstract: Apparatus for fixing a fracture of a bone including an elongated body member having a proximal end and a distal end for insertion into the intramedullary canal of the bone; a tab member having at least one aperture to allow for passage of a screw for fastening of the tab member to the bone; and a bolt for selectively removably coupling the tab member to the proximal end of the body member. Preferably, the tab member is of a hollow cylindrical configuration and removably interlocking the first plate member to a second plate member. In another embodiment, the apparatus include a body member for insertion into a bone cavity, the body member having at least one aperture disposed in close proximity to its first end to allow for passage of a screw for fastening the body member to the bone.
    Type: Grant
    Filed: March 4, 1991
    Date of Patent: April 13, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Michael W. Chapman, Dana C. Mears, Charles C. Edwards
  • Patent number: 5192326
    Abstract: A prosthetic nucleus for implantation in the disc space after removal of a damaged or degenerated nucleus is formed from a multiplicity of hydrogel beads having a water content of at least 30%. The beads are covered by a semi-permeable membrane. The membrane has porosity less than the size of the beads to thereby retain the beads therein but permit fluids to flow in and out of the prosthetic nucleus.
    Type: Grant
    Filed: September 9, 1991
    Date of Patent: March 9, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Qi-Bin Bao, Paul A. Higham
  • Patent number: 5190545
    Abstract: A bone fracture stabilization apparatus includes a cable positioning insert for a bone plate of the type having a series of apertures therein for receiving bone screws for attaching the bone plate to the bone. The cable positioning insert has a body shaped for at least partial insertion into at least one of the apertures of the bone plate. The insert further includes a flange extending from the body for engaging either the outer or inward surface of the bone plate. A boss extends from the body in a direction away from the bone when the bone plate is mounted thereon. The boss has at least one opening and preferably two openings therein for accommodating a cerclage cable and positioning it relative to the apertures in the bone. The boss may be made of a malleable material that deforms under pressure to flatten the openings therein and capture the cable.
    Type: Grant
    Filed: August 27, 1991
    Date of Patent: March 2, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: George M. Corsi, Richard M. Brooks, Paul J. Viola
  • Patent number: 5190544
    Abstract: A modular femoral internal implant system for use in the treatment of femoral disorders resulting from injury, disease or congenital defect includes at least three interconnectable components: 1) an elongated epiphyseal/metaphyseal implant, 2) an intramedullary rod and 3) an angled side plate having an elongated plate portion adapted to be secured to the outer cortical wall and a hollow sleeve adapted to extend into the femur. The epiphyseal/metaphyseal implant can be connected to either the angled side plate or the intramedullary rod. The system may also include an elongated bone plate connectable to the angled side plate, one or more additional epiphyseal/metaphyseal implants of variable length, an additional angled side plate, a distal buttress plate connectable to the elongated bone plate, and a plurality of bone screws of a universal design. Preferably, many or all of the components of the system are made of an inert, resilient titanium-base alloy.
    Type: Grant
    Filed: March 18, 1991
    Date of Patent: March 2, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Michael W. Chapman, Charles C. Edwards, Dana C. Mears
  • Patent number: 5181930
    Abstract: A beam adapted for implantation within a bone is able to support bending and torsional loading forces applied thereto. The beam has a stiffness defined by a modulus elasticity, which stiffness varies along the length of the beam to match the corresponding stiffness of the cortical bone adjacent the beam after implantation within the bone. The beam is made from an elongated core formed of continuous filament carbon fibers embedded in a thermoplastic polymer matrix with the carbon filaments extending in a direction substantially parallel to the longitudinal axis of the beam. Encasing the core is a filler molded to the core, which filler is made up of the same thermoplastic polymer as the core but contains no reinforcing carbon fibers. The filler provides the prosthesis with a shape generally conforming to the desired shape of the final prosthetic implant. A sheath formed of carbon reinforced filament fibers embedded in the thermoplastic polymer is wound in spiral formation around the filler and molded thereto.
    Type: Grant
    Filed: April 10, 1991
    Date of Patent: January 26, 1993
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: John H. Dumbleton, Ruey Y. Lin, Casper F. Stark, Thomas E. Crippen
  • Patent number: 5171243
    Abstract: An acetabular cup for use as a prosthetic implant has an insert with a body including a central bore for receiving a positioning rod therein. A key element is formed on the bore and is adapted to align the positioning rod. The insert has a locating element formed on an outer surface of the body and also includes spring elements extending radially outwardly from the body. The acetabular cup has a generally hemispherical shell member coupled to the outer surface of the insert. The shell has an outer surface for engaging the acetabulum and an inner surface having a circumferential groove for receiving the spring elements. The spring elements may be deflected radially inwardly out of engagement with the groove for releasing the insert from the shell. The shell has a plurality of apertures extending from its inner to its outer surface, which apertures are located in an asymmetrical pattern about the shell.
    Type: Grant
    Filed: October 22, 1991
    Date of Patent: December 15, 1992
    Assignee: Pfizer Hospital Products Group, Inc.
    Inventors: Glen A. Kashuba, Jon I. Klippel