Prosthesis for spinal repair

• US 3,867,728 A
• Filed: 04/05/1973
• Issued: 02/25/1975
• Est. Priority Date: 12/30/1971
• Status: Expired due to Term

• Current Assignee: James A. Stubstad, James R. Urbaniak, Paul Kahn
• Original Assignee: James A. Stubstad, James R. Urbaniak, Paul Kahn
• Inventors: Stubstad, James A., Kahn, Paul, Urbaniak, James R.
• Primary Examiner(s): Frinks, Ronald L.
• Application Number:
  US05/348,140
• Time in Patent Office: 691 Days
• Field of Search: 3/1 128/92C,92CA,92R,92G,334R,DIG.21
• US Class Current: 623/17.16
• CPC Class Codes: A61F 2/30724 Spacers for centering an implant in a bone cavity, e.g. in a cement-receiving cavity
• CPC Class Codes: A61F 2/30907 Nets or sleeves applied to surface of prostheses or in cement
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• CPC Class Codes: A61F 2/441 made of inflatable pockets or chambers filled with fluid, e.g. with hydrogel
• 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 2002/30069 elastomeric
• CPC Class Codes: A61F 2002/3007 Coating or prosthesis-covering structure made of elastic material, e.g. of elastomer
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/30133 kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/30293 Cylindrical body made by spirally rolling up a sheet or a strip around itself
• CPC Class Codes: A61F 2002/30451 soldered or brazed or welded
• CPC Class Codes: A61F 2002/30461 sutured, ligatured or stitched
• 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 2002/30604 modular
• CPC Class Codes: A61F 2002/30909 Nets
• CPC Class Codes: A61F 2002/30915 made of a stack of bonded perforated sheets, grids or wire meshes
• CPC Class Codes: A61F 2002/3092 having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/30929 having at least two superposed coatings
• CPC Class Codes: A61F 2002/30971 Laminates, i.e. layered products
• CPC Class Codes: A61F 2002/444 for replacing the nucleus pulposus
• CPC Class Codes: A61F 2002/4495 : having a fabric structure, e.g. made from wires or fibres
• CPC Class Codes: A61F 2210/0014 : using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2220/0058 : soldered or brazed or welded
• CPC Class Codes: A61F 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2230/0091 : helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts
• CPC Class Codes: Y10S 128/21 : Silicone

Abstract

A shaped article comprising at least a core element having generally flat top and bottom surfaces, the core element being made of elastic polymer and preferably reinforced. Presently preferred forms of the article are those in which the core element has a covering element secured to one or, in some cases, to both flat surfaces and providing an outer surface of an openpore tissue-ingrowth-receptive material. Another preferred form of the prosthesis comprises a curved, flat, bar-like element shaped into a spiral configuration, so that the overall appearance approximates a flat disc. Still another version includes a plurality of flexible, curved, bar-like elements with configurations which allow them to lie side by side so as to occupy the interior space of a natural disc from which the nucleus pulposus has been removed. When any form of the prosthesis is used to replace a diseased or damaged spinal disc, proper spacing of the adjacent vertebrae is maintained and the prosthesis provides resistance to compressive forces imposed on the spine, as well as preserves the natural flexibility of the spine.

Claims

1. A resilient shaped prosthesis for replacement of a damaged or degenerated spinal disc, comprising:

a spinal-disc-shaped element having two generally flat faces, and wherein said element is a laminated sandwich of horizontal shaped sheets of elastomer and horizontal shaped sheets of fabric-reinforced elastomer, all outer surfaces consisting of elastomer.

2. A resilient shaped prosthesis for replacement of a damaged or degenerated spinal disc, comprising:

a spinal-disc-shaped element having two generally flat faces, and wherein said element comprises a spirally-wound strip of fabric coated with and bonded by elastomer, all outer surfaces consisting of said elastomer.

3. A resilient shaped prosthesis for replacement of a damaged or degenerated spinal disc, comprising:

a spinal-disc-shaped element having two generally flat faces, wherein said element is a laminated sandwich of horizontal shaped sheets of elastomer and horizontal shaped sheets of fabric, and said spinal-disc-shaped element has, affixed to one said face of said element, an outward-facing covering of tissue-ingrowth-receptive, open-pore material.

4. The prosthesis of claim 3 wherein said material is on both said faces.

5. The prosthesis of claim 4 wherein said element has a concave side wall surface coterminous with an outer edge of said element at said faces and indented in between them.

6. A resilient, biocompatible, shaped prosthesis for replacement of a degenerated or damaged spinal disc including in combination:

a spinal-disc-shaped core element having a central portion of viscoelastic fluid polymer encased in a protecting and confining sac with two generally flat faces, a spinal-disc-shaped first closure element affiXed to one said face of said core element, and a spinal-disc-shaped second closure element affixed to the other said face of said core element, each of said closure elements having a flat elastomeric portion resting against one said face, and an outward-facing covering of tissue-ingrowth-receptive, open-pore fabric, all of said elements being firmly affixed together.

7. A resilient, bicompatible, shaped prosthesis for replacement of a degenerated or damaged spinal disc including in combination:

a spinal-disc-shaped core element having a central portion of unreinforced elastic polymer with two generally flat faces and a surrounding wall of reinforced polymer affixed to said central portion, a spinal-disc-shaped first outer element affixed to one said face of said core element, and a spinal-disc-shaped second outer element affixed to the other said face of said core element, each of said outer elements having a flat elastomeric portion resting against one said face, and an outward-facing covering of tissue-ingrowth-receptive, open-pore fabric, all of said elements being firmly affixed together.

8. The prosthesis of claim 7 wherein said reinforced surrounding wall is silicone elastomer reinforced with a mesh of fabric filaments.

9. The prosthesis of claim 8 wherein said surrounding wall has a posterior portion and additional means for rigidifying said posterior portion.

10. The prosthesis of claim 9 wherein said additional means comprises box sutures linking said posterior portion to opposite portions of said wall.

11. The prosthesis of claim 9 wherein said additional means comprises a rigid strip lying against the interior surface of said posterior portion.

12. The prosthesis of claim 7 wherein said surrounding wall is plurality of layers of silicone rubber, each layer being reinforced with Dacron mesh.

13. A resilient, bicompatible, shaped prosthesis for replacement of a degenerated or damaged spinal disc including in combination:

a spinal-disc-shaped core element having a central portion of elastic polymer with two generally flat faces, a spinal-disc-shaped first outer element affixed to one said face of said core element, and a spinal-disc-shaped second outer element affixed to the other said face of said core element, each of said outer elements having a flat elastomeric portion resting against one said face and comprising a plurality of silicone rubber layers in stacked arrangement, and an outward-facing covering of tissue-ingrowth-receptive, open-pore fabric, all of said elements being firmly affixed together.

14. The prosthesis of claim 13 wherein a reinforcing metal screen is incorporated into one of said silicone rubber layers.

15. The prosthesis of claim 13 wherein the outermost said silicone rubber layer is provided with an outer surface of Dacron velour.

16. A resilient, shaped prosthesis for replacement of a degenerated or damaged spinal disc, comprising:

a spinal-disc-shaped element having two generally flat faces and having a central portion consisting of elastic polymer compatible with body fluids and tissues, and a surrounding wall of reinforced elastomer affixed to said central portion.

17. The prosthesis of claim 16 wherein said polymer is a solid elastomer.

18. The prosthesis of claim 16 wherein said reinforced surrounding wall is of silicone elastomer reinforced with a mesh of fabric filaments.

19. A resilient, shaped prosthesis for replacement of a degenerated or damaged spinal disc, comprising:

a spinal-disc-shaped element having two generally flat faces and having a central portion consisting of elastic polymer compatible with body fluids and tissues, and a surrounding wall of reinforced elastomer affixed to said central portion, and wherein said polymer is a visco-elastic fluid encased in a protecting and confining sac.

20. A resilient, shaped prosthesis for replacement of a degenerated or damaged spinal disc, comprising:

a spinal-disc-shaped element having two generally flat faces and having a central portion consisting of elastic polymer compatible with body fluids and tissues, and a surrounding wall of reinforced elastomer affixed to said central portion, and said reinforced surrounding wall being made of silicone elastomer reinforced with a mesh of fabric filaments, and having a posterior portion and additional means for rigidifying said posterior portion.

21. The prosthesis of claim 20 wherein said additional means comprises box sutures linking said posterior portion to opposite portions of said wall.

22. The prosthesis of claim 21 wherein said additional means comprises a rigid strip lying against the interior surface of said posterior portion.

23. A resilient, shaped prosthesis for replacement of a degenerated or damaged spinal disc, comprising:

a spinal-disc-shaped element having two generally flat faces and having a central portion consisting of elastic polymer compatible with body fluids and tissues, and a surrounding wall of reinforced elastomer affixed to said central portion, and wherein said surrounding wall is a plurality of layers of silicone rubber, each layer being reinforced with Dacron mesh.

24. A resilient, shaped prosthesis for replacement of a damaged or a degenerated spinal disc including in combination:

a spinal-disc-shaped core element having two generally flat faces, a central portion of silicone elastomer, initially unvulcanized, a spinal-disc-shaped first outer covering element affixed to one said face of said core element, and a spinal-disc-shaped second outer covering element affixed to the other said face of said core element, each of said covering elements having a stack of flat elastomeric layers, with an inner initially unvulcanized layer resting against one side face and an initially vulcanized outer layer, and an outward-facing covering of tissue-ingrowth-receptive, open-pore fabric, secured to said outer layer, all of said elements being firmly affixed together by vulcanization together after assembly of said initially unvulcanized elastomeric layers and portions.

25. The prosthesis of claim 24 wherein said core element has a surrounding wall of silicone elastomer reinforced with fabric and initially vulcanized.

26. The prosthesis of claim 25 wherein said surrounding wall has a posterior portion and additional means for rigidifying said posterior portion.

27. The prosthesis of claim 26 wherein said additional means comprises Dacron box sutures spanning said surrounding wall.

28. The prosthesis of claim 26 wherein said additional means comprises a rigid strip lying against the interior surface of said posterior portion.

29. The prosthesis of claim 25 wherein said surrounding wall is a spirally-wound plurality of layers of silicone rubber, each layer being reinforced with Dacron mesh.

30. The prosthesis of claim 24 wherein a reinforcing metal screen is incorporated into a central, initially unvulcanized elastomeric layer between said outer layer and said inner layer.

31. The prosthesis of claim 24 wherein said outer elastomeric layer is provided with an outer surface of Dacron velour.

32. A resilient, biocompatible, shaped prosthesis for replacement of a degenerated or damaged spinal disc including in combination:

a spinal-disc-shaped core element having a central portion of fabric-reinforced elastic polymer with two generally flat faces of said polymer, a spinal-disc shaped outer element coterminous in area with said core element affixed to one said face only of said core element and having an outward-facing covering of tissue-ingrowth-receptive, open-pore fabric, all of said elements being firmly affixed together.

33. A resilient, shaped prosthesis for replacement of a damaged or a degenerated spinal disc including in combination:

a spinal-disc-shaped core element having first and second generally flat faCes and comprising fabric-reinforced elastomer, said faces having outer surfaces of said elastomer, a spinal-disc-shaped first outer covering element coterminous in area with and affixed to said first face of said core element, and a much smaller spinal-disc-shaped second outer covering element affixed to the central portion only of said second face of said core element, each of said covering elements having an outwardfacing covering of tissue-ingrowth-receptive, open-pore fabric, secured to said outer layer, all of said elements being firmly affixed together.

34. A resilient, shaped prosthesis for repair of a degenerated or damaged spinal disc, comprising:

a spiral sppinal-disc-shaped member having two generally flat faces and comprising a specially-covered bar-like elastomeric element compatible with body fluids and tissues, capable of being unwound into a long generally straight form and inherently tending to recoil itself, upon release, into its spiral spinal-disc shape.

35. The prosthesis of claim 34 wherein said elastomeric member comprises fabric-reinforced elastomer.

36. The prosthesis of claim 34 having an outer covering of tissue-ingrowth-receptive material on at least one said face.

37. The prosthesis of claim 34 having a core-stiffening yielding member embedded in at least its outermost terminal portion to aid in preventing bulging.

38. A resilient, shaped prosthesis for repair of a damaged or a degenerated spinal disc including in combination:

a generally spinal-disc-shaped assembly having two generally flat faces and comprising a plurality of curved segments arranged to nest in a horizontal manner when in place so as to provide said flat faces, each said segment being sufficiently narrow for installation through a narrow opening.

39. The prosthesis of claim 38 having an outward-facing covering of tissue-ingrowth-receptive, open-pore fabric, secured to one said face on each said segment.

40. A resilient, shaped prosthesis for replacement of a damaged or degenerated spinal disc, comprising:

a spinal-disc-shaped element having two generally flat faces, wherein said element comprises a spirally-wound strip of fabric coated with and bonded by elastomer and said element has, affixed to one said flat face, an outward-facing covering of tissue-ingrowth-receptive open-pore fabric.