Patents Assigned to Intermedics Orthopedics, Inc.
  • Patent number: 5639279
    Abstract: The present invention relates to prosthetic knee devices providing for an expanded range of translational movement without substantially reducing the risk of inadvertent dislocation of the knee when implanted. The devices of the invention achieve the expanded range of motion without requiring a substantial posterioral shifting of the points of contact between the femoral and tibial components. The prostheses of the invention also reduce the risk of breakdown of the plastic components of the prosthesis and the underlying resectioned proximal tibia surface by providing an expanded, winged fixation post.
    Type: Grant
    Filed: February 9, 1995
    Date of Patent: June 17, 1997
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Brian D. Burkinshaw, Lawrence D. Dorr, Wayne P. Gray
  • Patent number: 5554158
    Abstract: An intercondylar notch cutter using a plunge milling bit and bit guide which engages parallel tracks in a trial prosthesis. The intercondylar notch cutter comprises a cutting bit and a guide sleeve. The cutting bit can be thrust into the femur and then translated through the femur cutting a notch without removing the trial prosthesis. The bit is supported by a guide or housing with a guide platform which extends medially and laterally from the guide. Two condyle articulating surfaces on the platform slidingly engage a condyle surface on a trial prosthesis. Along the condyle surfaces on the trial prosthesis are two parallel grooves. Posts on the notch cutter are slidingly received within the grooves. A surgeon first places the trial implant on the femur without cutting an intercondylar notch. The surgeon can proceed immediately to cut an intercondyle notch without removing the femoral trial prosthesis.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: September 10, 1996
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: John D. Vinciguerra, Charles H. Perrone, Jr., Charles W. Mumme, Jeffery C. Higgins
  • Patent number: 5496323
    Abstract: An orthopedic instrument having a quarter-turn disconnect apparatus. A female socket is provided on a broach or cutting instrument and a male plug with a locking mechanism is provided on a cutting apparatus. The male plug is inserted into the socket and pushed forward slightly against the resistance of a spring. The plug or socket are then turned one-quarter turn at which point the locking mechanism falls into place.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: March 5, 1996
    Assignee: Intermedics Orthopedics, Inc.
    Inventor: Donald W. Dye
  • Patent number: 5490853
    Abstract: An orthopedic bone plug cutter for cutting a customized bone plug for use with prosthesis having stems of complex geometry, such as a cruciate stem. The bone plug cutter comprises an anvil which supports a piece of bone obtained intraoperatively. A specialized cutting head is forced against the anvil by a parallel jaw clamp. The cutting head can then be removed from the clamp and the bone plug extruded from the cutter with a plunger.
    Type: Grant
    Filed: June 8, 1994
    Date of Patent: February 13, 1996
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Brian D. Burkinshaw, John L. Wheeler
  • Patent number: 5486177
    Abstract: A patella planer for preparing a resected surface on a patella in a single operation. The patella planer has an adjustable stop which can be used on either side of the planer so that the planer may be used on the right or left knee. The adjustable stop has a floating zero pointer which can be set to accommodate varying thickness of the patient's patella. The amount of patella material to be removed can be selected by adjusting an offset stop pin.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: January 23, 1996
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Charles W. Mumme, Philip Gold
  • Patent number: 5480445
    Abstract: A tibial knee prosthesis having a plastic or polyethylene prosthesis body comprising an articulating surface and medullary stem. An intermediate metal plate locks on to the medullary stem and fits between the articulating surface and a resected proximal surface of the tibia. A distal surface of the plate may be provided with a porous coating adjacent the proximal resected surface of the tibia, to encourage bone ingrowth and fixation.
    Type: Grant
    Filed: June 9, 1994
    Date of Patent: January 2, 1996
    Assignee: Intermedics Orthopedics, Inc.
    Inventor: Brian D. Burkinshaw
  • Patent number: 5480452
    Abstract: A prosthesis having a proximal portion of a stem formed as a wedge having opposed tapers such that prostheses can be thrust into a medullary canal and achieve fixation without unduly stressing the cortical bone remaining in the femur. Ribs secure the prosthesis against medial-lateral motion. Simultaneously, a degree of flexibility is provided in an anterior-posterior direction. A slotted distal portion of the stem is flared to enhance fixation distally.
    Type: Grant
    Filed: October 21, 1993
    Date of Patent: January 2, 1996
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Aaron A. Hofmann, James E. Williams
  • Patent number: 5423827
    Abstract: A surgical jig for orienting a femoral component of a prosthetic knee prosthesis angularly with respect to the axis of the patient's femur which jig utilizes a single drill plate or guide for condylar pins, but permits variation in the placement of those pins. The jig comprises a distal plate which is placed against the distal end of the femur. The distal plate has two condyle fingers for grasping the posterior side of the femoral condyles. Gage means are provided to measure the size of the distal end of the femur. A rotatable drill guide permits the surgeon to adjust the placement of two drill bores for receiving condyle pins on a femoral component of a knee prosthesis.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: June 13, 1995
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Charles W. Mumme, Jeffery C. Higgins
  • Patent number: 5411505
    Abstract: A jig for resecting the distal end of a femur to receive a femoral component of a knee prosthesis. The jig has independent medial and lateral condyle sagittal saw guides. The guides aid a surgeon in cutting three of four resected surfaces or planes for each condyle. The femoral component accepts shims over either condyle to compensate for uneven loss of healthy bone. The shims do not change the internal geometry of the femoral component, but associate each proximal displacement with an anterior displacement of the geometry. Each saw guide slides on a slanted dovetail track so that the proper amount of anterior displacement can be maintained so that shims may maintain the common internal geometry.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: May 2, 1995
    Assignee: Intermedics Orthopedics, Inc.
    Inventor: Charles W. Mumme
  • Patent number: 5405349
    Abstract: An orthopedic jig or saw guide for preparing a femoral knee joint to receive the femoral component of a posterior stabilized prosthesis. The jig is adapted for cutting a central cavity in the distal end of the femur. In one embodiment, the cavity has a curved surface, the curve extending medial-laterally and a curved osteotome for incising a curved surface between the resulting two longitudinal incisions. The jig further comprises longitudinal saw guides for guiding a sagittal saw to make appropriate incisions parallel to the longitudinal axis of a femur.
    Type: Grant
    Filed: November 24, 1993
    Date of Patent: April 11, 1995
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Brian D. Burkinshaw, Wayne P. Gray
  • Patent number: 5405404
    Abstract: An apparatus for disassembling a head and acetabular component of a bipolar orthopedic hip prosthesis. The head includes a female taper configured for engaging a corresponding male taper of a femoral component of a hip prosthesis. The acetabular component includes a cavity in which the head is elastically constrained. The apparatus includes a rod having a male taper at one end thereof sized and configured to be received in taper locking engagement in the female taper of the head of the bipolar prosthesis. The rod has external threads that engage internal threads of a sleeve surrounding the rod. The sleeve includes a thrust surface at one end that engages the acetabular component as the sleeve is rotated relative to the rod. The sleeve causes the acetabular component to be pressed off of the head while the head remains taper locked to the rod. Continued rotation of the sleeve causes the head to be pressed off of the taper of the rod.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: April 11, 1995
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Kenneth J. Gardner, Adriana de la Barcena, Steven L. van der Meulen, Donald W. Dye, Amber E. Okoye, Mark L. Arlitt
  • Patent number: 5405402
    Abstract: An implantable prosthesis comprises a polyethylene prosthetic member that is substantially transparent to x-rays and a radiographic marker that is substantially opaque to x-rays. The radiographic marker is configured as a tension spring arranged as a continuous ring encircling the prosthetic member.
    Type: Grant
    Filed: April 14, 1993
    Date of Patent: April 11, 1995
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Donald W. Dye, Mark L. Arlitt
  • Patent number: 5405398
    Abstract: A posterior stabilized knee prosthesis with removable pin in the femoral component. The removable pin has a tapered split ring lock which prevents the pin from backing out. A split ring is provided on the pin which rides in a groove on the pin. When the pin is properly seated, the split ring engages a corresponding groove within the femoral prosthesis, locking the pin in place. Chamfers are provided on both the front and back of the split ring so that the split ring will compress as the pin is being screwed into the femoral component and also so that the pin can be removed if necessary.
    Type: Grant
    Filed: August 30, 1993
    Date of Patent: April 11, 1995
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Thomas B. Buford, III, Charles H. Perrone, Jr., Jeffery C. Higgins
  • Patent number: 5376124
    Abstract: A spacer to be used with femoral hip prostheses. The spacer is placed under a existing collar of a femoral hip prosthesis and cemented or tied in place or both. The spacer comprises a U-shaped segment adapted to fit under a medial collar and partially enclose part of a proximal portion of the stem of a hip prosthesis. Spacer plugs are provided to offset the spacer slightly and provide a space which is filled with bone cement (PMMA), securely attaching the spacer to the prosthesis. A distal ledge which lies adjacent the proximal body of the prosthesis keeps the cement enclosed between the stem and the spacer. An area of porous coating is provided distally. A peripheral groove is also provided.
    Type: Grant
    Filed: August 3, 1993
    Date of Patent: December 27, 1994
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Kenneth A. Gustke, Kenneth J. Gardner, James E. Williams
  • Patent number: 5364402
    Abstract: A tibial spacer saw guide for guiding the resection of a bony defect of the lateral or medial condyle of the proximal tibia to accommodate a spacer to be implanted beneath a tibial baseplate of a tibial prosthesis. The saw guide includes a plate having a plurality of locating holes corresponding in spacing and location to pins extending from the inferior surface of the tibial baseplate. The plate has medial and lateral guide edges for guiding a sagittal osteotomy where the guide edges are located relative to the locating holes, and thus relative to the pegs of the tibial baseplate. The saw guide also includes an anterior block extending from the plate and having a plurality of slots for guiding a horizontal osteotomy for the spacer of selected depth. The plate rests on an initially resected surface, and thus the horizontal osteotomy for the spacer is located relative to the initial osteotomy surface.
    Type: Grant
    Filed: July 29, 1993
    Date of Patent: November 15, 1994
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Charles W. Mumme, John D. Vinciguerra
  • Patent number: 5258035
    Abstract: A prosthesis having a proximal portion of a stem formed as a wedge having opposed tapers such that prostheses can be thrust into a medullary canal and achieve fixation without unduly stressing the cortical bone remaining in the femur. Ribs secure the prosthesis against medial-lateral motion. Simultaneously, a degree of flexibility is provided in an anterior-posterior direction. A slotted distal portion of the stem is flared to enhance fixation distally.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: November 2, 1993
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Aaron A. Hofmann, James E. Williams
  • Patent number: 5228437
    Abstract: An apparatus for detecting an electrical potential in a human body to control the delivery of a therapy. The electrical potential comprises a principal signal and a baseline signal. The apparatus samples the potential through an electrode during a selected interval and stores the value of that potential at the end of the interval. The stored value of the potential will be restored as an initial condition on the electrode at the end of a second interval after delivery of the therapy. In a heart pacemaker, the baseline signal is useful for controlling the output pulses of the pacemaker. The apparatus permits sensing of the baseline signal despite stimulating pulses and charge canceling.
    Type: Grant
    Filed: May 6, 1991
    Date of Patent: July 20, 1993
    Assignee: Intermedics Orthopedics, Inc.
    Inventor: Edward A. Schroeppel
  • Patent number: 5171248
    Abstract: An medullary caliper comprising a sleeve or tube with internally actuated caliper arms at a distal end thereof. The sleeve is graduated so that the depth at which a measurement is being taken can be immediately determined. A control rod extends the caliper arms radially outward within the medullary canal to perform the measurement. Displacement of the control rod is translated by a scale into a direct reading of the diametric dimension of the medullary canal.
    Type: Grant
    Filed: February 27, 1991
    Date of Patent: December 15, 1992
    Assignee: Intermedics Orthopedics, Inc.
    Inventor: John G. Ellis
  • Patent number: 5147365
    Abstract: A patella osteotomy guide comprising a plier-like appliance with curved jaws for grasping a patient's patella. A row of teeth faces inwardly from the jaws. The teeth are generally of pyramid shape, but a vertex of each tooth lies in a plane containing a bottom side of the respective jaw. Each of the jaws has an integral saw capture slot and the tips of the jaws are extended. A rotating, calibrated stylus measures the position of the patella with respect to the integral saw capture slots. The rotating stylus also functions as a pivot or fulcrum about which the jaws and handles of the osteotomy guide rotate. Handles for the osteotomy guide are offset from the plane of the jaws. The rotating stylus can be displaced up and down and then locked into a selected position using a draw bar and captured balls. A bowed retaining ring imparts a certain amount of pre-load to the stylus and draw bar assembly to hold the assembly in a selected position.
    Type: Grant
    Filed: August 19, 1991
    Date of Patent: September 15, 1992
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Steven I. Whitlock, Steven G. Brown
  • Patent number: 5112336
    Abstract: A drill guide and template for use in orthopedic surgery comprising a template and handle connected by a lockable universal joint. The handle further comprises a bent shaft. A template is provided with pins so that the template can be set into bone when accurately placed against a resected bony surface. The universal joint comprises a ball and socket joint with slots for increased adaptability. A threaded nut grips the ball against a distal end of the bent shaft. Tightening the nut onto shaft locks the ball in a selected position.
    Type: Grant
    Filed: May 14, 1991
    Date of Patent: May 12, 1992
    Assignee: Intermedics Orthopedics, Inc.
    Inventors: Janet L. Krevolin, Steven G. Brown