Implants for replacing hyaline cartilage, with hydrogel reinforced by three-dimensional fiber arrays

• US 20070224238A1
• Filed: 03/23/2006
• Published: 09/27/2007
• Est. Priority Date: 03/23/2006
• Status: Active Grant

• Current Assignee: Formae, Inc.
• Original Assignee: Formae, Inc.
• Inventors: Popper, Peter, Mansmann, Kevin
• Granted Patent: US 8,858,632 B2
• Time in Patent Office: Days
• US Class Current: 424/423
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• CPC Class Codes: A61F 2/468 Testing instruments for artificial joints for testing non-implantable prostheses A61F2/76
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/302 toroidal, e.g. rings
• CPC Class Codes: A61F 2002/30451 soldered or brazed or welded
• CPC Class Codes: A61F 2002/30892 parallel
• CPC Class Codes: A61F 2002/30914 Details of the mesh structure, e.g. disposition of the woven warp and weft wires
• CPC Class Codes: A61F 2002/30957 using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2002/4635 using minimally invasive surgery
• CPC Class Codes: A61F 2210/0019 operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: A61F 2230/0065 toroidal, e.g. ring-shaped, doughnut-shaped
• CPC Class Codes: A61L 2430/06 for cartilage reconstruction, e.g. meniscus
• CPC Class Codes: A61L 27/16 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/446 with other specific inorganic fillers other than those covered by A61L27/443 or A61L27/46
• CPC Class Codes: A61L 27/52 Hydrogels or hydrocolloids
• CPC Class Codes: C08L 33/20 : Homopolymers or copolymers of acrylonitrile C08L55/02 takes precedence
• CPC Class Codes: C08L 75/04 : Polyurethanes

Abstract

Implants with hydrogel layers reinforced by three-dimensional fiber arrays can replace hyaline cartilage. Such implants should replace an entire cartilage segment, rather than creating a crevice around a plug, so these implants must be thin and flat, they must cover large areas, the tips of any tufts or stitches must not reach the hydrogel surface, and they must be flexible, for arthroscopic insertion. The use of computerized stitching machines to create such arrays enables a redesigned and modified test sample to be made with no delays, and no overhead or startup costs. This provides researchers with improved tools for making and testing implants that will need to go through extensive in vitro, animal, and human testing before they can be approved for sale and use. Fiber-reinforced hydrogels also can be secured to strong shape-memory rims, for securing anchoring to bones.

Claims

1. An article of manufacture designed, sized, and suited for surgical implantation into a mammalian joint to replace hyaline cartilage, comprising a polymeric hydrogel material reinforced by a three-dimensional fiber array embedded within at least a portion of said polymeric hydrogel material.

2. The article of claim 1 wherein the three-dimensional fiber array comprises a backing layer, and a plurality of stitches that pass through said backing layer and are affixed to said backing layer.

3. The article of claim 2 wherein at least a portion of said three-dimensional fiber array comprises tufted loops.

4. The article of claim 2 wherein at least a portion of said three-dimensional fiber array comprises sewn stitches.

5. The article of claim 1, wherein said three-dimensional fiber array is affixed to an anchoring device that is designed, sized, and suited for surgical anchoring to a bone surface.

6. The article of claim 2, wherein said three-dimensional fiber array is affixed to an anchoring device that is designed, sized, and suited for surgical anchoring to a bone surface.

7. The article of claim 2, wherein said three-dimensional fiber array comprises a margin of unstitched backing material around at least a portion of its periphery.

8. The article of claim 6, wherein said three-dimensional fiber array is affixed to said anchoring device by means of an ultrasonically-welded attachment between a portion of said backing layer, and a polymeric component of said anchoring device.

9. The article of claim 2, wherein at least a portion of said stitches have been created by a computer-controlled stitching machine.

10. The article of claim 1, wherein said polymeric hydrogel material is a hydrophilic formulation of a polymer selected from the group consisting of polyacrylonitrile polymers and polyurethane polymers.

11. The article of claim 1, wherein the polymeric hydrogel material comprises at least one smooth surface that has no fibers exposed on said smooth surface.

12. A method for making a reinforced hydrogel implant component having dimensions suited for replacing hyaline cartilage in a mammalian joint, comprising the steps of:

(a) using stitching to affix tufted or sewn stitches to a backing layer, in a manner that will create a three-dimensional fiber array having a thickness suited for a reinforcing layer in an implant for replacing hyaline cartilage; and

,

(b) contacting said three-dimensional fiber array with a prepolymer liquid that will permeate into the three-dimensional fiber array and then polymerize to form a gelatinous solid that is affixed to and reinforced by said three-dimensional fiber array.

13. The method of claim 12 wherein said three-dimensional fiber array comprises tufted loops affixed to said backing layer.

14. The method of claim 12 wherein said three-dimensional fiber array comprises sewn stitches affixed to said backing layer.

15. The method of claim 12 wherein said three-dimensional fiber array is created by a computer-controlled stitching machine.

16. The method of claim 12 wherein said reinforced hydrogel implant component has at least one smooth surface that has no fibrous reinforcing material exposed on said smooth surface.