Patents Represented by Attorney, Agent or Law Firm Todd A. Dawson
  • Patent number: 5451228
    Abstract: A tibial resector guide having an angularly adjustable head controlled by a thumb actuated slide mechanism. The head may be positioned in a plurality of predetermined angular orientations in the anterior-posterior plane. The cutting head guide includes angled side walls which permit the guide to have a narrow aperture yet allow the saw blade to completely pass through the tibia. Further, the tibial resector of this invention includes a telescoping rod and a length adjustment mechanism adjacent the head for providing small height adjustments for positioning the head. The length adjustment member includes an enlarged thumb wheel to ease operation. A pinning platform is connected to the adjustment member such that it is shiftable with the adjustment member relative to the guide head. The pinning platform permits the surgeon to pin the upper end of the instrument to the patient's leg preventing movement of the instrument during resection.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: September 19, 1995
    Assignee: Zimmer, Inc.
    Inventors: Todd S. Johnson, Richard A. Lane, Thomas D. Petersen, Chuck Nichols, John R. Howard
  • Patent number: 5445640
    Abstract: A tibial resector guide having an angularly adjustable head controlled by a thumb actuated slide mechanism. The head may be positioned in a plurality of predetermined angular orientations in the anterior-posterior plane. The cutting head guide includes angled side walls which permit the guide to have a narrow aperture yet allow the saw blade to completely pass through the tibia. Further, the tibial resector of this invention includes a telescoping rod and a length adjustment mechanism adjacent the head for providing small height adjustments for positioning the head. The length adjustment member includes an enlarged thumb wheel to ease operation. A pinning platform is connected to the adjustment member such that it is shiftable with the adjustment member relative to the guide head. The pinning platform permits the surgeon to pin the upper end of the instrument to the patient's leg preventing movement of the instrument during resection.
    Type: Grant
    Filed: March 12, 1993
    Date of Patent: August 29, 1995
    Assignee: Zimmer, Inc.
    Inventors: Todd S. Johnson, Richard A. Lane, Thomas D. Petersen, Chuck Nichols, John R. Howard
  • Patent number: 5443510
    Abstract: The method forms a thin layer of metal mesh on the surface of the implant for the bonding with a porous surface layer to prevent the formation of notches within the body of the implant. The layer of metal mesh can be formed by a number of known methods including conventional welding processes such as arc welding, resistance welding, electron beam welding, laser beam welding, friction welding, ultrasonic welding, cladding. The porous metal surface layer is preferably formed from titanium wire or titanium beads in a known process. The porous surface layer is bonded by a known process such as diffusion bonding, sintering, welding, or cladding.By bonding the porous surface layer to the thin layer of metal mesh, notches normally formed in the body of the implant are substantially eliminated. Therefore, the designer of the implant is not limited as to the location and amount of porous surface layer to be placed on the implants.
    Type: Grant
    Filed: April 6, 1993
    Date of Patent: August 22, 1995
    Assignee: Zimmer, Inc.
    Inventors: H. Ravindranath Shetty, Clarence M. Panchison
  • Patent number: 5443512
    Abstract: An orthopaedic implant device is formed from, or defined by, a combination of different materials. These devices include a body metal component and a porous metal surface layer for intimate contact with bone and a polymer in the form of a casing that includes adhesive characteristics for attachment to the body metal component and the porous metal layer. The preferred polymer casing is polyaryletherketone.
    Type: Grant
    Filed: August 24, 1993
    Date of Patent: August 22, 1995
    Assignee: Zimmer, Inc.
    Inventors: Jack E. Parr, Roy D. Crowninshield, Thirumalai N. C. Devanathan, Helen Chu
  • Patent number: 5441501
    Abstract: A rasp-like instrument for forming a cavity in the intermedullary passage of a femur for the implantation of a femoral stem prosthesis. The rasp includes a detachable extension end which can be removed when the rasp is used to form the cavity for the primary implant stem and connected to provide a deeper cavity for the revision implant stem.
    Type: Grant
    Filed: June 20, 1994
    Date of Patent: August 15, 1995
    Assignee: Zimmer, Inc.
    Inventor: Roger R. Kenyon
  • Patent number: 5437671
    Abstract: The spinal rod system and perpendicular rod connector of the invention provides for a first rod to be connected by two pedicle screws transverse to the spine across a vertebra. The perpendicular connector is then connected to the first rod anywhere along the rod. The longitudinal spinal rod is then connected to the perpendicular rod connector using common connectors. The perpendicular connector is slidable along the first rod. By using the perpendicular rod connector, the amount of bending and the tolerances required is reduced as the connector may be slid along the transverse rod to accommodate the longitudinal rod. Known pedicle screws may be used with a slight bend placed in the transverse rod to accommodate the spinal column. Alternatively, the pedicle screws may be bent slightly such that a straight transverse rod may be used.
    Type: Grant
    Filed: March 7, 1994
    Date of Patent: August 1, 1995
    Assignee: Zimmer, Inc.
    Inventors: Antony J. Lozier, John R. Johnson, John R. Dimar, II
  • Patent number: 5431657
    Abstract: An instrument 2 used to install both the outer shell 40 and bearing liner 50 of a conventional acetabular cup assembly 4. Instrument 2 includes an impactor 30 and a reversible cup or head component 10, which is adapted for driving shell 40 into the acetabulum and for seating bearing liner 50 into the shell. Head component 10 has a rounded semi-spherical surface 12 on one end and a substantially flat surface 14 on the opposite end. Impactor 30 includes a longitudinal extension 36 which can be inserted into a bore 20 in head component 10 from either direction to secure the head component to the impactor. When instrument 2 is used to seat shell 40 into the acetabulum, head component 10 is fitted to impactor 30 with semi-spherical surface 12 facing outward for abutment against inner surface 44 of shell 40. Shell 40 is connected to the distal end 39 of extension 36, which protrudes from semi-spherical surface 12 of head component 10.
    Type: Grant
    Filed: May 23, 1994
    Date of Patent: July 11, 1995
    Assignee: Zimmer, Inc.
    Inventor: William Rohr
  • Patent number: 5405347
    Abstract: This invention provides for the angular and lateral adjustment of a pair of fixator rods in an infinite number of planes. The angular adjustment member may be rotated about a center axis of the connector such that the connected fixator rods may be angled relative to one another in any plane called for. Similarly, the lateral adjustment may be rotated about the center axis of the connector such that the two fixator rods may be shifted laterally relative to one another in any direction. The adjustable connector provides for the adjustment of the fixator rods after the rods have been connected to the bone pins. Therefore, after a surgeon has reduced and stabilized the fracture, minor adjustments can be carried out to fully align the bone fragments without disconnecting the fixator rods or the bone pins. After all adjustments have been made, a series of locking bolts or pins can be engaged to hold the adjustable connector in a fixed position.
    Type: Grant
    Filed: February 12, 1993
    Date of Patent: April 11, 1995
    Assignee: Zimmer, Inc.
    Inventors: Harry E. Lee, Thomas Russell, Aniruddha Nazre
  • Patent number: 5387243
    Abstract: The set of implants and method of this invention provide for the conversion of an implant 10 intended for cemented fixation to a bone to an implant 10' intended for non-cemented fixation to a bone. The set of implants include a plurality of pads 20 each having a porous surface layer 24 bonded to a plate 22. A thin layer 30 of thermoplastic polymer is bonded to the opposite side of the plate 22. The implant 10 is provided with a generally smooth outer surface and is intended for cemented use for fixation to the bone. However, if during surgery, the surgeon determines that the patient may be better suited for a non-cemented implant, the modular porous pads 20 may be bonded to the implant 10 to form an implant 10' intended for non-cemented fixation to the bone.
    Type: Grant
    Filed: November 23, 1992
    Date of Patent: February 7, 1995
    Assignee: Zimmer, Inc.
    Inventor: Thirumalai Devanathan
  • Patent number: 5383875
    Abstract: A control lever assembly adapted for use with a powered surgical instrument which prevents the instrument from being inadvertently or accidentally activated. The assembly 10 includes a depressible control lever 20 for controlling the action of the instrument and a second safety lever or latch 30 which engages the trigger pin 6 of instrument only when selectively positioned with respect to control lever 20. Control lever 20 is secured to cutting device 2 by a mounting bracket 12. Safety latch 30 is pivotally carried by control lever 20 for shiftable movement between a safety position and an operational position. In the operational position, safety latch 30 engages trigger pin 6 when control lever 20 is depressed. Safety latch 30 cannot be switched from its safety position to its operational position when control lever 20 is depressed; therefore, the instrument is "locked-out" and cannot be inadvertently activated even when control lever 20 is depressed.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: January 24, 1995
    Assignee: Zimmer, Inc.
    Inventors: Rodney Bays, Michael L. Boulton, John H. Pascaloff, Gregory C. Stalcup, Dai N. Vu
  • Patent number: 5383938
    Abstract: The metal lock ring of the invention has an oblong exterior periphery which allows the ring to have a small "width" and a larger "height." The small "width" provides a strong locking mechanism on the poly liner and the larger "height" allows the ring to remain secure within the groove of the metal shell prior to and during assembly of the polyethylene liner. The ring has a chamfer on its inside leading edges defining its width to facilitate assembly of the liner. This optimizes the ease of assembly and is simpler and more economically to produce than a chamfer all the way around the oblong ring. In the preferred embodiment, the lock ring has a constant thickness such that the inner periphery and the outer periphery are oval.In an alternative embodiment, the metal lock ring has a round inner diameter and a round outer diameter that are not concentric, thereby creating a thickening of the ring at one end.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: January 24, 1995
    Assignee: Zimmer, Inc.
    Inventors: William Rohr, Melissa Broderick, Tony Gonzalez
  • Patent number: 5364397
    Abstract: An instrument and method for locating and attaching a spinal coupler to an implanted spinal rod including body and lever handles that attach about the spinal rod. A cam handle is connected to the body handle to actuate a plunger that applies a compression force to the spinal coupler to attach it to the spinal rod by an interference fit. The body and lever handles each include a forked jaw having legs that attach to the spinal rod on each side of the spinal coupler. In one embodiment, the plunger includes a control knob to vary the instrument actuating force and prevent over extension of the plunger.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: November 15, 1994
    Assignee: Zimmer, Inc.
    Inventors: S. Kyle Hayes, Randall N. Allard
  • Patent number: 5364403
    Abstract: The acetabular cup positioner of this invention provides a resilient collar to be carried on its distal end for contacting the interior surface of the acetabular cup. The resilient collar prevents damage to the interior of the cup during impaction. Since the resilient collar will compress a small amount during the impaction, the threaded connector of the positioner and the threads for the acetabular cup will be under a sizable load. Therefore, to protect the positioner and the cup, the threaded connector is shiftably connected to the positioner body. The connector is biased toward the distal end by a helical spring.
    Type: Grant
    Filed: September 20, 1993
    Date of Patent: November 15, 1994
    Assignee: Zimmer, Inc.
    Inventors: Thomas D. Petersen, Richard A. Lane
  • Patent number: D355254
    Type: Grant
    Filed: October 29, 1993
    Date of Patent: February 7, 1995
    Assignee: Zimmer, Inc.
    Inventors: Petrus Krafft, Verlon C. Caldwell, Jr.
  • Patent number: D356730
    Type: Grant
    Filed: September 23, 1993
    Date of Patent: March 28, 1995
    Assignee: Hall Surgical, Division of Zimmer, Inc.
    Inventor: William R. Lee
  • Patent number: D357315
    Type: Grant
    Filed: March 15, 1993
    Date of Patent: April 11, 1995
    Assignee: Zimmer, Inc.
    Inventor: Terry L. Dietz
  • Patent number: D360686
    Type: Grant
    Filed: November 12, 1993
    Date of Patent: July 25, 1995
    Assignee: Zimmer, Inc.
    Inventors: G. Kris Kumar, Hershel E. Francher, David Glass
  • Patent number: D361029
    Type: Grant
    Filed: February 7, 1994
    Date of Patent: August 8, 1995
    Assignee: Hall Sugrical
    Inventor: Gregory A. Goris
  • Patent number: D362068
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: September 5, 1995
    Assignee: Zimmer, Inc.
    Inventors: Gary J. Baker, Kevin T. Dunn, Ryder L. Russell
  • Patent number: D363545
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: October 24, 1995
    Assignee: Zimmer, Inc.
    Inventor: Stephen C. Miller