Artificial intervertebral disc

• US 5,458,643 A
• Filed: 02/01/1994
• Issued: 10/17/1995
• Est. Priority Date: 03/29/1991
• Status: Expired due to Term

• Current Assignee: BMG, Inc.
• Original Assignee: Kabushiki Kaisha Biomaterial Universe Corporation of Japan, Kyocera Corporation
• Inventors: Okimatsu, Hideaki, Ikada, Yoshito, Gen, Shokyu, Oka, Masanori
• Primary Examiner(s): ISABELLA, DAVID J
• Application Number:
  US08/189,603
• Time in Patent Office: 623 Days
• Field of Search: 623/16, 623/17, 623/18, 623/20, 623/22, 623/23, 623/66
• US Class Current: 623/17.16
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• CPC Class Codes: A61F 2/3603 implanted without ablation of the whole natural femoral head endoprosthetic cartilage A61F2/30756
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2002/30113 circular
• CPC Class Codes: A61F 2002/30125 elliptical or oval
• CPC Class Codes: A61F 2002/30133 kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/30153 rectangular
• CPC Class Codes: A61F 2002/30154 square
• CPC Class Codes: A61F 2002/30156 triangular
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/30263 cubical
• CPC Class Codes: A61F 2002/3028 polyhedral different from parallelepipedal and pyramidal
• CPC Class Codes: A61F 2002/30563 having elastic means or damping means, different from springs, e.g. including an elastomeric core or shock absorbers
• CPC Class Codes: A61F 2002/30673 Lubricating means, e.g. synovial pocket
• CPC Class Codes: A61F 2002/30915 made of a stack of bonded perforated sheets, grids or wire meshes
• CPC Class Codes: A61F 2002/30971 Laminates, i.e. layered products
• CPC Class Codes: A61F 2230/0006 : circular
• CPC Class Codes: A61F 2230/0008 : elliptical or oval
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2230/0019 : rectangular
• CPC Class Codes: A61F 2230/0021 : square
• CPC Class Codes: A61F 2230/0023 : triangular
• CPC Class Codes: A61F 2230/0063 : Three-dimensional shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0082 : parallelepipedal
• CPC Class Codes: A61F 2230/0084 : cubical
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00203 : containing alumina or aluminium oxide
• CPC Class Codes: A61L 27/16 : obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/52 : Hydrogels or hydrocolloids
• CPC Class Codes: C08L 29/04 : Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids

Abstract

A prosthesis used for a damaged bone, an artificial articular cartilage or an artificial intervertebral disc being characterized in that the prosthesis is a composite body comprising polyvinyl alcohol hydrogel and ceramic or metallic porous body. With this prosthesis, PVA hydrogel enhances lubrication and shock absorbing functions, and the porous body allows the ingrowth and ossification of the bone tissue of a living body therein to affinitively connect said hydrogel to the bones of the living body.

Claims

1. A prosthesis used for replacing at least one of a damaged bone, an articular cartilage and an intervertebral disc, the prosthesis comprising:

polyvinyl alcohol hydrogel and a porous body, the porous body comprising at least one of a ceramic material and a metallic material, wherein

the hydrogel is carried into the porous body via infiltration and fixation, thereby forming a resulting porous body having a shape corresponding to the at least one of a damaged bone, an articular cartilage and an intervertebral disc it replaces, and wherein

the resulting porous body is positioned at and brought into contact with articular bone portions so that bone tissue is allowed to grow into and ossify within the resulting porous body to connect the hydrogel to bone portions of a living body.

2. The prosthesis of claim 1, comprising:

a pair of porous bodies, the pair of porous bodies comprising at least one of a pair of metallic bodies and a pair of ceramic bodies, and

a polyvinyl alcohol hydrogel block integrally incorporated between the pair of porous bodies.

3. The prosthesis of claim 2, wherein the polyvinyl alcohol hydrogel is carried by the porous body contacting the hydrogel block via infiltration and fixation.