Prosthetic apparatus and method

• US 6,764,514 B1
• Filed: 04/26/2000
• Issued: 07/20/2004
• Est. Priority Date: 04/26/1999
• Status: Expired due to Fees

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: SDGI Holdings Incorporated (Medtronic Plc)
• Inventors: Li, Rhodemann, Li, Lehmann K.
• Primary Examiner(s): Pellegrino, Brian E
• Application Number:
  US09/559,899
• Time in Patent Office: 1,546 Days
• Field of Search: 623/17.11, 623/17.12, 623/17.16, 623/6.13, 623/6.59, 606/61, 606/99
• US Class Current: 623/17.12
• CPC Class Codes: A61F 2/0095 Packages or dispensers for prostheses or other implants for intraocular lenses A61F2/1691; for dental surgery A61C19/02
• 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 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/30019 differing in mechanical expandability, e.g. in mechanical, self- or balloon expandability
• CPC Class Codes: A61F 2002/30075 swellable, e.g. when wetted
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• 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 2002/30136 undulated or wavy, e.g. serpentine-shaped or zigzag-shaped
• CPC Class Codes: A61F 2002/30138 Convex polygonal shapes
• CPC Class Codes: A61F 2002/30225 Flat cylinders, i.e. discs
• CPC Class Codes: A61F 2002/30293 Cylindrical body made by spirally rolling up a sheet or a strip around itself
• CPC Class Codes: A61F 2002/30324 differing in thickness
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30494 Cooperating protrusions and recesses, e.g. radial serrations, located on abutting end surfaces of a longitudinal connection
• 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 2002/30579 : with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30586 : having two or more inflatable pockets or chambers
• CPC Class Codes: A61F 2002/30588 : filled with solid particles
• CPC Class Codes: A61F 2002/30593 : hollow
• CPC Class Codes: A61F 2002/30599 : stackable
• CPC Class Codes: A61F 2002/30772 : Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/444 : for replacing the nucleus pulposus
• CPC Class Codes: A61F 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4635 : using minimally invasive surgery
• CPC Class Codes: A61F 2210/0014 : using shape memory or superelastic materials, e.g. nitinol
• 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 2210/0023 : operated at different temperatures whilst inside or touching the human body, heated or cooled by external energy source or cold supply
• CPC Class Codes: A61F 2210/0061 : swellable
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2230/0004 : Rounded shapes, e.g. with rounded corners
• 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 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0091 : helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: A61F 2250/0018 : differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0036 : differing in thickness
• CPC Class Codes: A61F 2250/0048 : differing in mechanical expandability, e.g. in mechanical, self- or balloon expandability
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts

Abstract

A prosthetic nucleus for implantation in a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus from the chamber, comprising a wafer of biologically compatible, thin, flexible, and expandable material in a selected first configuration. The wafer is adapted to be re-shaped mechanically into a compact second configuration of cross-section sufficiently small to permit travel of the wafer through a cannula and into the disc chamber. The wafer is further adapted to substantially regain the first configuration thereof by memory upon entry into the disc chamber, and the wafer is adapted to react to an expansion-inducing agent in the disc chamber to expand to an enlarged and selected third configuration.

Claims

1. A prosthetic intervertebral nucleus for implantation in a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus from the chamber, the prosthetic nucleus comprising:

a wafer of biologically compatible, thin, flexible, and expandable material having a first substantially planar structural configuration defining a first thickness substantially less than a height of the disc chamber;

said wafer having a second non-planar mechanically re-shaped structural configuration defining a cross-section sufficiently small to permit travel of said wafer through a cannula and into the disc chamber;

said wafer substantially regaining the first structural configuration thereof by memory upon entry into the disc chamber; and

said wafer having a third expanded structural configuration formed by a reaction to an expansion-inducing agent in the disc chamber, said third structural configuration defining a second thickness approximately equal to the height of the disc chamber.

2. A prosthetic nucleus in accordance with claim 1 wherein the first configuration of said wafer is at least one of circular, annular, oval, kidney, polygonal, symmetrical, and asymmetrical.

3. A prosthetic nucleus in accordance with claim 1 wherein the expansion-inducing agent comprises a selected one of temperature in the chamber;

a substance in the chamber; and

a substance introduced into the nucleus in the chamber.

4. A prosthetic nucleus in accordance with claim 3 wherein the expansion-inducing substance comprises a fluid.

5. A prosthetic nucleus in accordance with claim 4 wherein the fluid is water.

6. A prosthetic nucleus in accordance with claim 4 wherein said wafer, in the third configuration, exhibits elastic properties providing the disc with shock-absorber capabilities.

7. A prosthetic nucleus in accordance with claim 1 wherein said wafer is provided with fenestrations.

8. A prosthetic nucleus in accordance with claim 1 wherein said wafer is adapted to expand in a selected direction so as to assume the third configuration.

9. A prosthetic nucleus in accordance with claim 1 wherein said wafer is provided with at least one additional component to facilitate return of said wafer from said second configuration to said first configuration for stability and strength.

10. A prosthetic nucleus in accordance with claim 1 wherein said wafer is provided with an internal chamber.

11. A prosthetic intervertebral nucleus for implantation in a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus from the chamber, the prosthetic nucleus comprising:

a wafer of biologically compatible, thin, flexible, and expandable material having a first substantially planar structural configuration;

said wafer having a second non-planar mechanically re-shaped structural configuration defining a cross-section sufficiently small to permit travel of said wafer through a cannula and into the disc chamber, said second non-planar structural configuration comprising at least one of a rolled, curled and folded configuration;

said wafer substantially regaining the first structural configuration thereof by memory upon entry into the disc chamber; and

said wafer having a third expanded structural configuration formed by a reaction to an expansion-inducing agent in the disc chamber.

12. A prosthetic nucleus in accordance with claim 11 wherein said wafer regains the first configuration by one of unrolling, uncurling and unfolding.

13. A prosthetic intervertebral nucleus for implantation in a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus from the chamber, the prosthetic nucleus comprising:

a wafer of biologically compatible, thin, flexible, and expandable material having a first substantially planar structural configuration defining a first thickness substantially less than a height of the disc chamber;

said wafer having a second non-planar collapsed structural configuration defining a cross-section sufficiently small to permit travel of said wafer through a cannula and into the disc chamber; and

said wafer having a third expanded structural configuration formed by a reaction to an expansion-inducing agent in the disc chamber, said third structural configuration defining a second thickness approximately equal to the height of the disc chamber.

14. A prosthetic intervertebral nucleus for implantation in a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus from the chamber, the prosthetic nucleus comprising:

a wafer of biologically compatible, thin, flexible, and expandable material having a first substantially planar structural configuration;

said wafer having a second non-planar collapsed structural configuration defining a cross-section sufficiently small to permit travel of said wafer through a cannula and into the disc chamber, said second non-planar structural configuration comprising at least one of a rolled, curled and folded configuration; and

said wafer having a third expanded structural configuration formed by a reaction to an expansion-inducing agent in the disc chamber.

15. A prosthetic intervertebral nucleus for implantation into a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus, the prosthetic nucleus comprising:

an implant having a first substantially planar structural configuration, said implant having a second non-planar collapsed structural configuration for insertion into the disc chamber, said second non-planar structural configuration comprising a rolled configuration, said implant substantially regaining said first substantially planar structural configuration by memory upon entry into the disc chamber said implant having a third expanded structural configuration formed by a reaction to an expansion-inducing agent within the disc chamber.

16. The prosthetic nucleus in accordance with claim 15 wherein said implant is inserted through a cannula while in said second configuration and into the disc chamber.

17. A prosthetic intervertebral nucleus for implantation into a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus, the prosthetic nucleus comprising:

an implant having a first substantially planar structural configuration, said implant having a second non-planar collapsed structural configuration for insertion into the disc chamber, said second non-planar structural configuration comprising a rolled configuration, said implant substantially regaining said first substantially planar structural configuration by memory upon entry into the disc chamber, said implant comprising a wafer of biologically compatible, thin, flexible and expandable material.

18. A prosthetic intervertebral nucleus for implantation into a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus, the prosthetic nucleus comprising:

an implant having a first substantially planar structural configuration, said implant having a second non-planar collapsed structural configuration for insertion into the disc chamber, said second non-planar structural configuration comprising a curled configuration, said implant substantially regaining said first substantially planar structural configuration by memory upon entry into the disc chamber, said implant having a third expanded structural configuration formed by a reaction to an expansion-inducing agent within the disc chamber.

19. The prosthetic nucleus in accordance with claim 18 wherein said implant is inserted through a cannula while in said second configuration and into the disc chamber.

20. A prosthetic intervertebral nucleus for implantation into a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus, the prosthetic nucleus comprising:

an implant having a first substantially planar structural configuration, said implant having a second non-planar collapsed structural configuration for insertion into the disc chamber, said second non-planar structural configuration comprising a curled configuration, said implant substantially regaining said first substantially planar structural configuration by memory upon entry into the disc chamber, said implant comprising a wafer of biologically compatible, thin, flexible and expandable material.

21. A prosthetic intervertebral nucleus for implantation into a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus, the prosthetic nucleus comprising:

an implant having a first substantially planar structural configuration, said implant having a second non-planar collapsed structural configuration for insertion into the disc chamber, said second non-planar structural configuration comprising a folded configuration, said implant substantially regaining said first substantially planar structural configuration by memory upon entry into the disc chamber, said implant having a third expanded structural configuration formed by a reaction to an expansion-inducing agent within the disc chamber.

22. The prosthetic nucleus in accordance with claim 21 wherein said implant is inserted through a cannula while in said second configuration and into the disc chamber.

23. A prosthetic intervertebral nucleus for implantation into a chamber of an intervertebral disc after removal of at least a portion of a damaged or degenerated nucleus, the prosthetic nucleus comprising:

an implant having a first substantially planar structural configuration, said implant having a second non-planar collapsed structural configuration for insertion into the disc chamber, said second non-planar structural configuration comprising a folded configuration, said implant substantially regaining said first substantially planar structural configuration by memory upon entry into the disc chamber, said implant comprising a wafer of biologically compatible, thin, flexible and expandable material.

24. The prosthetic nucleus in accordance with claim 23 wherein said implant has a third expanded structural configuration formed by a reaction to an expansion-inducing agent within the disc chamber.