Craniofacial implant

• US 8,298,292 B2
• Filed: 06/02/2006
• Issued: 10/30/2012
• Est. Priority Date: 04/16/2003
• Status: Active Grant

• Current Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Original Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Inventors: Swords, Greg, Noble, Aaron M.
• Primary Examiner(s): Isabella, David
• Assistant Examiner(s): SCHILLINGER, ANN M
• Application Number:
  US11/445,560
• Publication Number:
  US 20060224242A1
• Time in Patent Office: 2,342 Days
• Field of Search: 623 1717- 1719, 623 235- 2376, 606/151, 606/213, 606/215
• US Class Current: 623/23.72
• CPC Class Codes: A61B 17/8085 with pliable or malleable elements or having a mesh-like structure, e.g. small strips A61B17/8071, A61B17/8076 take precedence
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61F 2/02 Prostheses implantable into the body closure means for urethra or rectum or for artificial body openings therefor A61F2/0004
• CPC Class Codes: A61F 2/2803 for mandibular reconstruction temporo-mandibular joints A61F2/3099; bone plates for the jaw A61B17/8071
• CPC Class Codes: A61F 2/2875 Skull or cranium A61F2/2803 and A61F2/3099 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 2002/2878 for orbital repair
• CPC Class Codes: A61F 2002/30065 thermoplastic, i.e. softening or fusing when heated, and hardening and becoming rigid again when cooled
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/30578 having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30677 Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/30787 inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30957 using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2002/3096 trimmed or cut to a customised size
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0071 thermoplastic
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00323 containing titanium nitride
• CPC Class Codes: A61F 2310/00407 : Coating made of titanium or of Ti-based alloys
• 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 27/56 : Porous materials, e.g. foams or sponges
• CPC Class Codes: C08L 23/06 : Polyethene

Abstract

A composite surgical implant that is made of a planar sheet of a thermoplastic resin that includes a top surface, a bottom surface, and a surgical grade metal mesh or metal plates contained therein. The implant may be bent by hand, wherein upon the displacement of the implant, the implant will generally maintain the shape to which it has been displaced.

Claims

1. A surgical implant for bone repair comprising a first surface and a second surface, the implant comprising a porous thermoplastic matrix having an interconnected pore structure throughout the matrix, and a surgical grade metal mesh embedded within the porous thermoplastic matrix such that the matrix encases the mesh and fills interstices of the mesh, and wherein the implant is bendable or displaceable by manipulation by hand, wherein upon the displacement of the implant, the implant will generally maintain the shape to which it has been bent or displaced in a rigid and fixed position for attachment to bone, wherein the mesh provides a structure for attachment to bone.

2. The implant recited in claim 1, wherein the metal comprises titanium, surgical grade stainless steel, steel coated with titanium, titanium nitride, titanium alloyed with other metals, composites of any of the above materials, or any combination thereof.

3. The implant recited in claim 1, wherein the thermoplastic matrix comprises polyethylene, high density polyethylene, ultra high molecular weight polyethylene, polyether ether ketone, thermoplastic resins, polyethylene terephthalate, nylon, polypropylene, polyolefin, any polymer of aliphatic hydrocarbons containing one or more double bonds, composites of any of the above materials, or any combination thereof.

4. The implant recited in claim 1, wherein the first surface, the second surface, or both surfaces comprise a non-porous barrier layer surface.

5. The implant recited in claim 1, wherein the first surface, the second surface, or both surfaces comprise a porous surface having pores sized to allow fibrovascular ingrowth into the porous thermoplastic matrix.

6. The implant recited in claim 5, wherein pore sizes range from about 20 to about 500 microns.

7. The implant recited in claim 1, wherein one of the first or second surfaces comprises a non-porous barrier layer surface and the other of the first or second surfaces comprises a porous surface.

8. The implant recited in claim 1, further comprising one or more attachment structures adapted to attach the implant to a desired surface.

9. The implant as recited in claim 8, wherein the one or more attachment structures comprise openings in the implant and through the mesh that will receive and engage the head of a surgical screw or surgical bone anchor.

10. The implant as recited in claim 8, wherein the one or more attachment structures comprise one or more strands of rings that are adapted to receive a fixation device.

11. The implant as recited in claim 8, wherein the one or more attachment structures comprise a portion of mesh extending from the encased mesh and the porous thermoplastic matrix of the implant.

12. The implant as recited in claim 8, wherein the one or more attachment structures comprise an angled bracket.

13. The implant as recited in claim 1, wherein the implant is provided in a particular shape to approximately fit a particular surgical site.

14. The implant as recited in claim 1, wherein the implant further comprises cells or biologically active molecules.

15. The implant as recited in claim 1, wherein the implant comprises openings, grooves, or channels that are adapted to accommodate nerves or vessels that may lie underneath the implant during use.

16. The implant as recited in claim 1, wherein the implant is provided in a kit of implants having varied features.

17. The implant of claim 16, wherein the varied features comprise one or more of varied thicknesses, mesh patterns, strengths, sizes, shapes, malleability, seeding options, or combinations thereof.

18. The implant of claim 1, wherein the metal mesh is sized to allow load bearing reconstructions of the mandible or long bones, and the thermoplastic matrix provides volume filling capacity for resected or deficient bony structures, further comprising a non-porous barrier surface on at least the first or second surface of the implant.

19. The implant of claim 1, wherein the surgical grade metal mesh has shape memory.

20. The implant of claim 1, wherein the surgical grade metal mesh comprises wire screen, expanded metal, perforated metal sheet, perforated bars, an interconnected meshwork of perforated bars, a three-dimensional grid, a free form solid, a perforated or machined shaped sheet, or any combination thereof.

21. A surgical implant for bone repair comprising a matrix of porous polyethylene having an interconnected pore structure throughout the matrix and a surgical grade metal mesh embedded in the matrix such that the porous polyethylene matrix fills spaces within the mesh and encases the mesh, wherein all surfaces of the matrix comprise pores that are sized between 20-500 microns, the implant further comprising one or more attachment structures extending from the implant and adapted to attach the implant to bone, and wherein the implant is able to be bent or displaced by manipulation by hand such that the implant will generally maintain the shape to which it has been bent or displaced in a rigid and fixed position for attachment to bone, wherein the mesh provides a structure for attachment to bone.

22. The surgical implant of claim 21, wherein the implant further comprises a first surface and a second surface with a layer of a non-porous polyethylene on the porous polyethylene matrix forming the first and second surfaces.

23. The implant as recited in claim 21, wherein the one or more attachment structures comprise one or more strands of rings that are adapted to receive a fixation device, one or more angled brackets, or at least a portion of the mesh extending away from the encased mesh and the matrix of porous polyethylene.

24. A surgical implant for bone repair comprising a matrix of porous polyethylene having an interconnected pore structure throughout the matrix and a surgical grade metal mesh embedded in the matrix such that the porous polyethylene matrix fills spaces within the mesh and encases the mesh, the implant having a first surface and a second surface, wherein the first surface comprises a non-porous layer of polyethylene on the porous polyethylene matrix and the second surface and all other sides of the implant comprise the matrix of porous polyethylene with pores that are sized between 20-500 microns, the implant further comprising one or more attachment structures extending from the implant and adapted to attach the implant to bone, and wherein the implant is able to be bent or displaced by manipulation by hand such that the implant will generally maintain the shape to which it has been bent or displaced in a rigid and fixed position for attachment to bone, wherein the mesh provides a structure for attachment to bone.

25. The implant as recited in claim 24, wherein the one or more attachment structures comprise one or more strands of rings that are adapted to receive a fixation device, one or more angled brackets, or at least a portion of the mesh extending away from the encased mesh and the matrix of porous polyethylene.