Spinal surgical prosthesis

• US 20020128716A1
• Filed: 02/07/2002
• Published: 09/12/2002
• Est. Priority Date: 07/26/1999
• Status: Active Grant

• Current Assignee: East Coast Medical & Dental Devices, Inc.
• Original Assignee: Advanced Prosthetic Technologies, Inc.
• Inventors: Cohen, Howard, Biro, Ladislau, Cohen, Matthew S.
• Granted Patent: US 6,719,796 B2
• Time in Patent Office: Days
• US Class Current: 623/17.15
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• 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 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• CPC Class Codes: A61F 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30237 partial tubes
• CPC Class Codes: A61F 2002/30329 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2002/3037 Translation along the common longitudinal axis, e.g. piston
• CPC Class Codes: A61F 2002/30372 with additional means for limiting said translation
• CPC Class Codes: A61F 2002/30383 made by laterally inserting a protrusion, e.g. a rib into a complementarily-shaped groove
• CPC Class Codes: A61F 2002/30392 Rotation
• CPC Class Codes: A61F 2002/304 : with additional means for limiting said sliding
• CPC Class Codes: A61F 2002/30411 : having two threaded end parts connected by a threaded central part with opposite threads at its opposite ends, i.e. for adjusting the distance between both end parts by rotating the central part
• CPC Class Codes: A61F 2002/30471 : connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2002/30487 : Circumferential cooperating grooves and beads on cooperating lateral surfaces of a mainly longitudinal connection
• 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 2002/30507 : using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30518 : with possibility of relative movement between the prosthetic parts
• CPC Class Codes: A61F 2002/30523 : by means of meshing gear teeth
• CPC Class Codes: A61F 2002/30538 : for adjusting angular orientation
• CPC Class Codes: A61F 2002/3054 : about a connection axis or implantation axis for selecting any one of a plurality of radial orientations between two modular parts, e.g. Morse taper connections, at discrete positions, angular positions or continuous positions
• CPC Class Codes: A61F 2002/3055 : for adjusting length
• CPC Class Codes: A61F 2002/30556 : for adjusting thickness
• 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 2002/30566 : Helical springs
• CPC Class Codes: A61F 2002/30593 : hollow
• CPC Class Codes: A61F 2002/30599 : stackable
• CPC Class Codes: A61F 2002/30601 : telescopic
• CPC Class Codes: A61F 2002/30604 : modular
• CPC Class Codes: A61F 2002/30677 : Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/30774 : internally-threaded
• CPC Class Codes: A61F 2002/30785 : parallel
• CPC Class Codes: A61F 2002/3083 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30975 : made of two halves
• CPC Class Codes: A61F 2002/4485 : comprising three or more adjacent spinal implants
• CPC Class Codes: A61F 2002/449 : comprising multiple spinal implants located in different intervertebral spaces or in different vertebrae
• CPC Class Codes: A61F 2210/0004 : bioabsorbable
• 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 2220/0091 : connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2250/0006 : for adjusting angular orientation
• CPC Class Codes: A61F 2250/0009 : for adjusting thickness
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

A prosthesis in the form of a cage having opposed complimentary bearing surface assemblies. The bearing surface assemblies moveable towards and away from each other. The moving mechanism being part of the bearing surface assemblies. Each of the bearing surface assemblies having an outer bearing surface whereby movement of one bearing surface assembly in one direction will move the bearing surface assemblies away from each other and movement in the opposite direction will move the bearing surface assemblies towards each other.

Claims

1. A prosthesis comprising at least one set of opposed complimentary bearing surface assemblies, means for moving said bearing surface assemblies towards and away from each other, said moving means being integral of the bearing surface assemblies, each of said bearing surface assemblies having an outer bearing surface whereby movement by the moving means in one direction will move the bearing surface assemblies away from each other and movement by moving means in the opposite direction will move the bearing surface assemblies towards each other, thereby increasing and decreasing, respectively, the height of said prosthesis.

2. The prosthesis as set forth in claim 1 wherein each of said opposed bearing surface assemblies comprise top and bottom sections, each section having an outer bearing surface with an inner face and a wall extending therefrom, said wall comprising at least one inclined cam surface extending substantially vertically from the inner face of said bearing surface and away therefrom.

3. The prosthesis as set forth in claim 2 wherein partition means are provided on each section, said partition means extending substantially vertically and away from the inner face of said bearing surface.

4. The prosthesis as set forth in claim 3 wherein said wall comprises a plurality of inclined cam surfaces.

5. The prosthesis as set forth in claim 4 wherein said partition means of each of said sections comprises a pair of outer partitions and an inner partition, wherein said outer partitions of said top section engage said inner partition of said bottom section and said outer partitions of said bottom section engage said inner partition of said top section to allow movement of said top section relative to said bottom section.

6. The prosthesis as set forth in claim 5 wherein each of said cam surfaces having an edge, teeth are provided at said edge of said cam surfaces.

7. The prosthesis as set forth in claim 6 wherein openings are provided in each of said wall to facilitate movement of said top section relative to said bottom section.

8. The prosthesis as set forth in claim 6 wherein an opening is provided in the center of each of said outer bearing surfaces.

9. The prosthesis as set forth in claim 6 wherein ridges are provided on the outer bearing surfaces of each of said bearing surface assemblies.

10. The prosthesis as set forth in claim 6 wherein channels are provided on the outer bearing surfaces of each of said bearing surface assemblies, said channels radiating outwardly from the center of said outer bearing surfaces.

11. The prosthesis as set forth in claim 6 wherein means are mounted between said top and bottom sections in order to bias said top and bottom sections toward each other.

12. The prosthesis as set forth in claim 11 in which said biasing means are spring means.

13. The prosthesis as set forth in claim 6 in which all the outer bearing surfaces of said bearing surface assemblies are supported.

14. The prosthesis as set forth in claim 13 in which said teeth of said top section corresponds with said teeth of said bottom section such that said teeth from said top and bottom sections are contained within said prosthesis.

15. The prosthesis as set forth in claim 6 in which said wall and said cam surfaces are curved.

16. The prosthesis as set forth in claim 6 in which said teeth having rounded edges.

17. The prosthesis as set forth in claim 6 in which a plurality of openings are provided on said outer bearing surfaces.

18. The prosthesis as set forth in claim 6 wherein said opposed bearing surface assemblies has bio-resorbable material between said edges of said cam surfaces and a bellows surrounds said bearing surface assemblies.

19. The prosthesis as set forth in claim 6 wherein connecting means is interposed between said two sections and each end of said connecting means having inclined cam surfaces, teeth on its edges, and inner and outer partitions thereof whereby the connecting means may be rotated relative to the two sections.

20. The prosthesis as set forth in claim 6 comprising two or more sets of opposed complimentary bearing surface assemblies, wherein said bottom sections of said two or more sets are joined together by a web and each of said set of bearing surface assemblies being individually and independently adjustable to act as a leveling device.

21. The prosthesis as set forth in claim 1 wherein said outer bearing surfaces are curved and wherein said moving means is between said curved outer bearing surfaces.

22. The prosthesis as set forth in claim 20 wherein gear means are mounted between the curved outer bearing surfaces.

23. The prosthesis as set forth in claim 22 wherein said gear means have threaded extensions adapted to be threadably mounted in threaded openings in the curved outer bearing surfaces.

24. The prosthesis as set forth in claim 23 in which a pair of gear means are mounted between the outer bearing surfaces, said gear means mutually movable relative to each other.

25. The prosthesis as set forth in claim 1 wherein between said bearing surface assemblies is a substance that promotes osseous integration and bone in-growth.

26. The prosthesis as set forth in claim 1 wherein between said bearing surface assemblies is a substance with hemostatic factors to control bleeding.

27. The prosthesis as set forth in claim 1 wherein between said bearing surface assemblies is a substance with anti-viral drugs to control and prevent infection.

28. The prosthesis as set forth in claim 1 wherein said bearing surface assemblies are connected together by cross-arms and have a jack-screw interposed therebetween, one end of each arm being mounted on a bearing surface and the other end of said arm being mounted on the jack screw.

29. The prosthesis as set forth in claim 1 wherein wedge means are interposed between said bearing surface assemblies, said wedge means being connected together by a screw and said wedge means movable in a groove in each of said bearing surface assemblies.

30. The prosthesis as set forth in claim 29 in which said wedge means comprise a pair of opposed wedge blocks threadably mounted for movement on the screw and having opposed inclined wedge surfaces.

31. The prosthesis as set forth in claim 1 further comprises a resilient disc between said bearing surface assemblies and a bio-degradable band around said disc.

32. The prosthesis as set forth in claim 2 further comprises a resilient disc between the outer bearing surface of said top section of one set of bearing surface assembly and the outer bearing surface of said bottom section of another set of bearing surface assembly.

33. The prosthesis as set forth in claim 1 wherein cam surfaces are mounted between said bearing surface assemblies, said cam surfaces being mounted on a cam screw.

34. The prosthesis as set forth in claim 20 further comprises a curved outer bearing surface extension attached to said outer bearing surfaces of each of said bearing surface assemblies, wherein said bearing surface assemblies being individually adjustable.

35. The prosthesis as set forth in claim 1 further comprises a non-expandable core, said core having expandable bearing surfaces extending therefrom, wedge means extending between said expandable bearing surfaces whereby rotation of the wedge means in one direction moves the outer bearing surfaces apart.

36. The prosthesis as set forth in claim 1 comprising two or more sets of opposed complimentary bearing surface assemblies, each of said bearing surface assemblies having geared teeth extending therefrom whereby movement of one set of geared teeth will move the other set of geared teeth in order to adjust the distance between the outer bearing surfaces of all bearing surface assemblies and the height of said prosthesis.

37. The prosthesis as set forth in claim 1 wherein one set of bearing surface assemblies is mounted between an intermediate vertebrae and an upper vertebrae and another set of bearing surface assemblies is mounted between said intermediate vertebrae and a lower vertebrae, wherein connecting and stabilizing means are mounted between the spaced bearing surface assemblies.

38. The prosthesis as set forth in claim 37 wherein said connecting and stabilizing means comprises a clamping plate attachable to said intermediate vertebrae, said clamping plate having connecting and stabilizing rods extending therefrom, and said connecting rods extending beyond said intermediate vertebrae and abutting said walls of said bearing surface assemblies.

39. The prosthesis as set forth in claim 1 wherein a rigid bio-resorbable material is provided between said bearing surface assemblies and wherein flexible resilient bearing means are mounted between and engage said bearing surface assemblies, whereby upon degradation of said bio-resorbable material, the flexible and resilient means will remain between said bearing surface assemblies.

40. A method of employing a spinal prosthesis for achieving stability of adjacent vertebrae and preserving the inter-disc space comprising the steps of:

surgically exposing an area for placement of said spinal prosthesis between adjacent vertebrae;

inserting said prosthesis in said space between adjacent vertebral end plates;

providing said prosthesis with outer bearing surfaces abutting adjacent bone structure on said vertebral end plates;

providing osseous integration and bone in-growth through said outer bearing surfaces of said prosthesis;

providing said prosthesis a rigid bio-compatible, bio-resorbable material to maintain said space between said vertebral end plates, whereby osseous integration causing solidification of said vertebral end plates with said bearing surfaces of said prosthesis and said rigid bio-resorbable material being resorbed, allowing said prosthesis to become flexible and still maintain the established inter-disc space created by said prosthesis originally.

41. The method as in claim 40 wherein said bio-compatible, bio-resorbable material is a polymer that is photocurable by ultra-violet light in the range of 350-385 nanometers in wavelength.

42. The method as in claim 40 wherein said bio-compatible, bio-resorbable material is a polymer that is photocurable by visible light in the range of 385-550 nanometers in wavelength.

43. The method as in claim 42 wherein said bio-resorbable material contains substance that promotes osseous integration and bone in-growth.

44. The method as in claim 42 wherein said bio-resorbable material is pliable and putty-like in an uncured state and not pliable in the cured state.

45. The method as in claim 44 wherein said bio-resorbable material is colored in an uncured state and turns clear in the cured state.

46. The method as in claim 42 wherein said bio-resorbable material contains hemostatic factors to control bleeding.

47. The method as in claim 42 wherein said bio-resorbable material contains antiviral drug to control and prevent infection.

48. The method as in claim 42 wherein said bio-resorbable material contains radiation beads.