Bone grafts

• US 6,371,988 B1
• Filed: 01/18/2000
• Issued: 04/16/2002
• Est. Priority Date: 10/23/1996
• Status: Expired due to Term

• Current Assignee: SDGI Holdings Incorporated (Medtronic Plc)
• Original Assignee: SDGI Holdings Incorporated (Medtronic Plc)
• Inventors: Pafford, John, McKay, William F., Boyd, Lawrence M., Ray, Eddie F. III, Van Hoeck, James E.
• Primary Examiner(s): ISABELLA, DAVID J
• Application Number:
  US09/484,354
• Time in Patent Office: 819 Days
• Field of Search: 623/16.11, 623/17.11, 623/17.16, 623/23.61, 623/23.63, 606/61
• US Class Current: 623/17.11
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61B 2090/034 abutting on parts of the device itself
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• 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 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• 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 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4603 for insertion or extraction of endoprosthetic joints or of accessories thereof
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/468 Testing instruments for artificial joints for testing non-implantable prostheses A61F2/76
• 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 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/2839 Bone plugs or bone graft dowels
• CPC Class Codes: A61F 2002/30004 the prosthesis being made from materials having different values of a given property at different locations within the same prosthesis
• CPC Class Codes: A61F 2002/30057 made from both cortical and cancellous adjacent parts
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30075 : swellable, e.g. when wetted
• CPC Class Codes: A61F 2002/30112 : Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2002/30136 : undulated or wavy, e.g. serpentine-shaped or zigzag-shaped
• CPC Class Codes: A61F 2002/30153 : rectangular
• CPC Class Codes: A61F 2002/30187 : D-shaped or half-disc-shaped
• CPC Class Codes: A61F 2002/30224 : cylindrical
• CPC Class Codes: A61F 2002/30235 : tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30261 : parallelepipedal
• CPC Class Codes: A61F 2002/30593 : hollow
• CPC Class Codes: A61F 2002/30677 : Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/30772 : Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30774 : internally-threaded
• CPC Class Codes: A61F 2002/30787 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30797 : internally-threaded
• CPC Class Codes: A61F 2002/30813 : Stepped or enlarged blind bores, e.g. having discrete diameter changes
• CPC Class Codes: A61F 2002/30836 : knurled
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30845 : with cutting edges
• CPC Class Codes: A61F 2002/3085 : with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• CPC Class Codes: A61F 2002/30866 : Rounded threads
• CPC Class Codes: A61F 2002/30879 : Ribs
• CPC Class Codes: A61F 2002/30892 : parallel
• CPC Class Codes: A61F 2002/30904 : serrated profile, i.e. saw-toothed
• 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 2002/448 : comprising multiple adjacent spinal implants within the same intervertebral space or within the same vertebra, e.g. comprising two adjacent spinal implants
• 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 2002/4628 : with linear motion along or rotating motion about an axis transverse to the instrument axis or to the implantation direction, e.g. clamping
• CPC Class Codes: A61F 2002/4649 : Bone graft or bone dowel harvest sites
• CPC Class Codes: A61F 2210/0004 : bioabsorbable
• CPC Class Codes: A61F 2210/0061 : swellable
• CPC Class Codes: A61F 2230/0004 : Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2230/0019 : rectangular
• CPC Class Codes: A61F 2230/0034 : D-shaped
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0082 : parallelepipedal
• CPC Class Codes: A61F 2250/0014 : having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis
• CPC Class Codes: A61F 2310/00161 : Carbon; Graphite
• CPC Class Codes: A61F 2310/00293 : containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61F 2310/00365 : Proteins; Polypeptides; Degradation products thereof
• CPC Class Codes: A61F 2310/00491 : Coating made of niobium or Nb-based alloys
• CPC Class Codes: A61F 2310/00544 : Coating made of tantalum or Ta-based alloys
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite
• CPC Class Codes: A61L 2300/252 : Polypeptides, proteins, e.g. glycoproteins, lipoproteins, cytokines
• CPC Class Codes: A61L 2300/414 : Growth factors
• CPC Class Codes: A61L 2300/802 : Additives, excipients, e.g. cyclodextrins, fatty acids, surfactants
• CPC Class Codes: A61L 2430/38 : for reconstruction of the spine, vertebrae or intervertebral discs
• CPC Class Codes: A61L 27/10 : Ceramics or glasses
• CPC Class Codes: A61L 27/12 : Phosphorus-containing materials, e.g. apatite
• 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 27/227 : Other specific proteins or polypeptides not covered by A61L27/222, A61L27/225 or A61L27/24
• CPC Class Codes: A61L 27/24 : Collagen
• CPC Class Codes: A61L 27/54 : Biologically active materials, e.g. therapeutic substances A61L27/227 takes precedence
• CPC Class Codes: A61L 31/024 : Carbon; Graphite
• CPC Class Codes: A61L 31/026 : Ceramic or ceramic-like structures, e.g. glasses
• CPC Class Codes: A61L 31/044 : Collagen
• CPC Class Codes: A61L 31/047 : Other specific proteins or polypeptides not covered by A61L31/044 - A61L31/046
• CPC Class Codes: A61L 31/048 : obtained by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: A61L 31/06 : obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: Y10S 606/907 : Composed of particular material or coated
• CPC Class Codes: Y10S 606/908 : Bioabsorbable material
• CPC Class Codes: Y10S 606/909 : Bone
• CPC Class Codes: Y10S 606/91 : Polymer

Abstract

Spinal spacers 20 are provided for fusion of a motion segment. The spacers include a load bearing member 21 having a wall 22 sized for engagement within a space between adjacent vertebrae to maintain the space and an effective amount of an osteogenic composition to stimulate osteoinduction. The osteogenic composition includes a substantially pure osteogenic factor in a pharmaceutically acceptable carrier. In one embodiment the load bearing member includes a bone graft impregnated in an osteogenic composition. In another embodiment, the osteogenic composition 30 is packed within a chamber 25 defined in the graft. Any suitable configuration of a bone graft is contemplated, including bone dowels, D-shaped spacers and cortical rings.

Claims

1. A hollow spinal spacer for engagement between vertebrae, comprising:

an anterior wall having a convexly curved anterior surface and opposite ends;

a posterior wall having a flat posterior surface and opposite ends;

two lateral walls, each integrally connected between said opposite ends of said anterior and posterior walls to define a chamber; and

said walls comprised of bone and further defining;

a superior face defining a first opening, said opening in communication with said chamber, said superior face having a superior engaging surface; and

an opposite inferior face defining a second opening, said second opening in communication with said chamber, said inferior face having an inferior engaging surface.

2. The spacer of claim 1 wherein said bone is cortical bone obtained from the diaphysis of a long bone having a medullary canal, said chamber including a portion of the medullary canal.

3. The spacer of claim 1, further comprising an effective amount of an osteogenic composition to stimulate osteogenesis, said composition disposed within said chamber.

4. The spacer of claim 1 wherein said osteogenic composition includes a material selected from the group consisting of autograft, allograft, a bioceramic and a substantially pure osteogenic factor in a pharmaceutically acceptable matrix.

5. The spacer of claim 4 wherein said bioceramic is a biphasic calcium phosphate ceramic.

6. The spacer of claim 4 wherein said factor includes a bone morphogenic protein selected from the group consisting of BMP-1, BMP-2, BMP-3, BMP-4, BMP-5, BMP-6, BMP-7, BMP-8, BMP-9, BMP-10, BMP-11, BMP-12 and BMP-13, a mixture thereof and a heterodimer thereof.

7. The spacer of claim 6 wherein said matrix is selected from the group consisting of calcium sulphates, polylactic acids, polyanhydrides, collagen, calcium phosphates and polymeric acrylic esters.

8. The spacer of claim 1 wherein said anterior wall defines a tool engaging hole for receiving an implanting tool.

9. The spacer of claim 8 wherein said tool engaging hole is threaded for receiving a threaded implanting tool.

10. The spacer of claim 1 wherein at least one of said engaging surfaces are roughened.

11. The spacer of claim 1 wherein at least one of said engaging surfaces includes teeth.

12. The spacer of claim 1 wherein at least one of said engaging surfaces defines a waffle pattern.

13. The spacer of claim 1 further comprising a blade on at least one of said engaging surfaces.

14. The spacer of claim 1 wherein said wall defines a bone growth thru-hole therethrough, said thru-hole communicating with said chamber and sized to receive mesenchymal cells.

15. A spinal spacer, comprising a load bearing member of cortical bone obtained from a cross-sectional slice of the diaphysis of a long bone having a medullary canal, said member having a wall, a superior surface and an inferior surface said wall sized for engagement within an intervertebral space and defining a chamber, said chamber including a portion of the canal, at least one of said surfaces defining surface roughenings for engaging the endplates of adjacent vertebrae.

16. The spacer of claim 15, wherein said surface roughenings are selected from the group consisting of knurlings, a waffle pattern, and teeth.

17. The spacer of claim 15, wherein said spacer further comprises an effective amount of an osteogenic composition to stimulate osteogenesis, said composition disposed within said chamber.

18. The spacer of claim 17, wherein said osteogenic composition is a material selected from the group consisting of autograft, allograft, a bioceramic and a substantially pure osteogenic factor in a pharmaceutically acceptable matrix.

19. The spacer of claim 18, wherein said osteogenic factor is a bone morphogenic protein.

20. The spacer of claim 19, wherein said bone morphogenic protein is selected from the group consisting of BMP-1, BMP-2, BMP-3, BMP-4, BMP-5, BMP-6, BMP-7, BMP-8, BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, mixtures thereof and heterodimers thereof.

21. The spacer of claim 18, wherein said bioceramic is a biphasic calcium phosphate ceramic.

22. The spacer of claim 15, wherein said load bearing member is a cortical ring.

23. The spacer of claim 15, wherein said wall is cylindrical and said load bearing member has a diameter larger than the height of the intervertebral disc space.

24. The spacer of claim 17, wherein said osteogenic composition has a length greater than the length of said chamber.

25. The spacer of claim 15, wherein said spacer further comprises an effective amount of an osteogenic composition to stimulate osteogenesis, said body impregnated with said composition.

26. The spacer of claim 15, wherein said spacer has an outer surface that defines a tool engaging hole for receiving an implanting tool.

27. The spacer of claim 26, wherein said tool-engaging hole is threaded to receive a threaded implanting tool.

28. A spinal spacer, comprising a load bearing member of bone obtained from the diaphysis of a long bone having a medullary canal, said member having a wall, a superior surface and an inferior surface, said wall sized for engagement within an intervertebral space and defining a chamber, said chamber including a portion of the canal, at least one of said surfaces defining surface roughenings for engaging the endplates of adjacent vertebrae, said surface roughenings selected from the group consisting of knurlings, a waffle pattern, and teeth.

29. The spacer of claim 28, wherein said spacer further comprises an effective amount of an osteogenic composition to stimulate osteogenesis, said composition disposed within said chamber.

30. The spacer of claim 29, wherein said osteogenic composition is a material selected from the group consisting of autograft, allograft, a bioceramic and a substantially pure osteogenic factor in a pharmaceutically acceptable matrix.

31. The spacer of claim 30, wherein said osteogenic factor is a bone morphogenic protein.

32. The spacer of claim 31, wherein said bone morphogenic protein is selected from the group consisting of BMP-1, BMP-2, BMP-3, BMP-4, BMP-5, BMP-6, BMP-7, BMP-8, BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, mixtures thereof and heterodimers thereof.

33. The spacer of claim 31, wherein said bioceramic is a biphasic calcium phosphate ceramic.

34. The spacer of claim 29, wherein said bone comprises cortical bone.

35. The spacer of claim 34, wherein said load bearing member is a cortical ring.

36. The spacer of claim 29, wherein said wall is cylindrical and said load bearing member has a diameter larger than the height of the intervertebral disc space.

37. The spacer of claim 30, wherein said osteogenic composition has a length greater than the length of said chamber.

38. The spacer of claim 29, wherein said spacer further comprises an effective amount of an osteogenic composition to stimulate osteogenesis, said bone impregnated with said composition.

39. The spacer of claim 29, wherein said spacer includes a tool engaging portion defining a tool engaging hole for receiving an implanting tool.

40. The spacer of claim 39, wherein said tool engaging hole is threaded to receive a threaded implanting tool.