Abstract: The present invention discloses a method for enhancing the wear-resistance of polymers by crosslinking them, especially before irradiation sterilization. In particular, this invention presents the use of chemically crosslinked ultrahigh molecular weight polyethylene in in vivo implants.
Type:
Grant
Filed:
September 27, 1999
Date of Patent:
August 28, 2001
Assignees:
The Orthopaedic Hospital, University of Southern California
Inventors:
Ronald Salovey, Harry A. McKellop, Fu-Wen Shen
Abstract: An article for use in the preparation of a hydrogel prosthetic nucleus, for an intervertebral disc, having equilibrium water contents (EWCs) of from about 30 to about 90% and compressive strengths of at least 4 meganewtons per square meter (MNm−2), at their EWCs, when subjected to the same constraints as the normal nucleus, comprising one or more xerogel rods containing from zero to less than the EWC.
Abstract: A resorbable interbody fusion device for use in spinal fixation is disclosed. The device is composed of 25-100% bioresorbable or resorbable material. The interbody fusion device of the invention can be in any convenient form, such as a wedge, screw or cage. Preferably, the resorbable device of the invention is in the shape of a tapered wedge or cone, which further desirably incorporates structural features such as serrations or threads better to anchor the device in the adjoining vertebrae. The preferred device further comprises a plurality of peripheral voids and more desirably a central void space therein, which may desirably be filled with a grafting material for facilitating bony development and/or spinal fusion, such as an autologous grafting material.
Type:
Grant
Filed:
August 10, 1998
Date of Patent:
June 5, 2001
Assignee:
Cambridge Scientific, Inc.
Inventors:
Joseph D. Gresser, Debra J. Trantolo, Robert S. Langer, Kai-Uwe Lewandrowski, Alexander M. Klibanov, Donald L. Wise
Abstract: A highly porous three-dimensional biodegradable poly(organophosphazene) matrix with hydrolytically unstable side chains is prepared and used as a scaffold for the growth of osteoblast cells. In a preferred embodiment, the poly(organophosphazene) includes between 10 and 90% hydrolytically unstable side chains including glucosyl, glyceryl, glyceryl, imidazolyl or ethoxy units, for example, poly[(methylphenoxy)(ethyl glycinato) phosphazene]. The addition of the glucosyl, glycinyl or glyceryl side chains to the polymer can also be used generally to enhance growth rates of cells adhered to the polymer, presumably through uptake and metabolism of the simple sugar or alcohol units.
Type:
Grant
Filed:
April 4, 1994
Date of Patent:
May 22, 2001
Assignees:
The Penn State Research Foundation, Massachusetts Institute of Technology
Inventors:
Cato T. Laurencin, Saadiq El-Amin, Archel M. A. Ambrosio, Shawn R. Pucher, Harry R. Allcock
Abstract: The present invention relate to a poly(vinyl alcohol) hydrogel construct having a wide range of mechanical strengths for use as a human tissue replacement. The hydrogel construct may include a tissue scaffolding, a low bearing surface within a joint, or any other structure which is suitable for supporting the growth of tissue.
Abstract: Disclosed are methods for soft tissue augmentation in a mammal wherein a composition comprising a biocompatible polymer having a water equilibrium content of less than about 15% and a biocompatible solvent is delivered to the tissue of the mammal to be augmented.
Type:
Grant
Filed:
December 15, 1998
Date of Patent:
May 15, 2001
Assignee:
Enteric Medical Technologies, Inc.
Inventors:
Richard J. Greff, David E. Silverman, Alan Stein
Abstract: An implantable prosthesis includes a porous polymeric member having pores present in its wall structure wherein these pores contain a variety of therapeutically useful compositions including, collagen, genetically altered cells and piezoelectric materials. A process of preparing such a prosthesis is also disclosed.
Abstract: This invention provides molded, biodegradable porous polymeric implant materials having a pore size distribution throughout the material which is substantially uniform. These materials can be molded into implants of any desired size and shape without loss of uniformity of pore size distribution. The implants are useful as biodegradable scaffolds for cell growth in healing of tissue defects. When manufactured to have an aspect ratio greater than about 3, the implants can be further hand-shaped to fit the defect into which they are placed and the desired shape for the regrown tissue.
Type:
Grant
Filed:
January 21, 1999
Date of Patent:
March 20, 2001
Assignee:
OsteoBiologics, Inc.
Inventors:
Mary Ann Walter, Neil C. Leatherbury, Mark Q. Niederauer
Abstract: A prosthetic bone filler including ceramic granules for use in a living body, the ceramic granules being bonded to each other with a polymeric substance, and having ventilation pores produced as a result of the presence of gaps between the adjacent granules. The prosthetic bone filler is produced by adding the polymeric substance in two portions to the ceramic granules. In addition to good flexibility, the prosthetic bone filler exhibits excellent bio-compatibility.
Abstract: A medical implant, tubing and method to provide enhanced X-ray detection intensity in catheters, stents, vascular grafts or other tubular implants. In one aspect the medical implant includes a visually transparent radiopaque polymer and a filler material having a radiopaque component.
Abstract: The present invention provides methods for modifying surfaces made from metal alloy and/or UHMWPE, preferably surfaces which are frictionally engaged, e.g., in an orthopaedic implant. The methods of the present invention reduce the coefficient of friction of the metal alloy component, reduce the shearing of fibrils from the UHMWPE component, and reduce sub-surface fatigue in the UHMWPE component. The method involves solvent immersion of the UHMWPE component to remove short chains of polyethylene at or near the surface of the component, and to swell and toughen the subsurface of the component. The method also involves firmly coating the surface of the metal alloy component with an adherent layer of diamond-like carbon (“DLC”) by creating a metal-silicide interface at the surface of the metal alloy to permit firmer adhesion of DLC.
Type:
Grant
Filed:
April 30, 1997
Date of Patent:
January 9, 2001
Assignee:
Southwest Research Institute
Inventors:
Geoffrey Dearnaley, James Lankford, Jr.
Abstract: An ultra high molecular weight polyethylene molded article for artificial joints has molecular orientation or crystal orientation in the molded article, and is low in friction and is superior in abrasion resistance, and therefore is available as components for artificial joints. Further, the ultra high molecular weight polyethylene molded article for artificial joints can be used as a component for artificial hip joints (artificial acetabular cup), a component for artificial knee joints (artificial tibial insert) and the socket for artificial elbow joints, and in addition to the medical use, it can be applied as materials for various industries by utilizing the characteristics such as low friction and superior abrasion resistance.