Continuous phase compositions for ACL repair

• US 8,535,357 B2
• Filed: 02/05/2007
• Issued: 09/17/2013
• Est. Priority Date: 12/09/2004
• Status: Active Grant

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Sports Medicine LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Stone, Kevin T., Borden, Mark D.
• Primary Examiner(s): Truong, Kevin T
• Assistant Examiner(s): BATES, DAVID W
• Application Number:
  US11/702,448
• Publication Number:
  US 20070141110A1
• Time in Patent Office: 2,416 Days
• Field of Search: 606/76, 606/77, 606/301, 606/304, 606/314, 606/321, 606/323, 606/305, 606/300, 411/403, 411/407, 424/426
• US Class Current: 606/300
• CPC Class Codes: A61B 17/864 hollow, e.g. with socket or cannulated
• CPC Class Codes: A61B 17/866 Material or manufacture
• CPC Class Codes: A61B 2017/00004 (bio)absorbable, (bio)resorbable or resorptive
• CPC Class Codes: A61F 2/0811 Fixation devices for tendons or ligaments
• CPC Class Codes: A61F 2002/0858 Fixation of tendon or ligament between anchor and bone, e.g. interference screws, wedges
• CPC Class Codes: A61F 2002/0882 Anchor in or on top of a bone tunnel, i.e. a hole running through the entire bone
• CPC Class Codes: A61F 2250/003 differing in adsorbability or resorbability, i.e. in adsorption or resorption time

Abstract

An implantable interference screw for use in a soft tissue repair, the screw having a bioresorbable body comprising a plurality of interconnected pores, the body having an instrument interface in one end and a thread around an exterior of the body starting from distal end. The plurality of interconnected pores of the resorbable body are substantially filled with a bioresorbable polymer.

Claims

1. An implantable interference screw for use in soft tissue repair, the screw comprising:

a substantially-cylindrical ceramic body having a tapered end, at least a portion of said ceramic body comprising a plurality of interconnected pores;

an instrument interface at the end of said ceramic body opposite to said tapered end, wherein a first volume of a bioresorbable polymer is structurally reinforcing said instrument interface;

a thread starting near said tapered end, and surrounding at least a portion of a surface of said ceramic body; and

a second volume of the bioresorbable polymer filling at least a portion of said plurality of interconnected pores.

2. A screw according to claim 1 further comprising a coating covering at least a portion of a surface of said plurality of interconnected pores.

3. A screw according to claim 1 wherein said plurality of pores have a size of from about 350 microns to about 550 microns.

4. A screw according to claim 1 wherein said ceramic body is bioresorbable.

5. A screw according to claim 4 wherein said ceramic body and said bioresorbable polymer are bioresorbable at different rates.

6. A screw according to claim 1 wherein said ceramic body comprises a material selected from the group consisting of calcium phosphate, calcium carbonate, calcium oxide, calcium sulfate, hydroxyapatite, magnesium calcium phosphate, and combinations thereof.

7. A screw according to claim 1 wherein said bioresorbable polymer is selected from the group consisting of aliphatic polyesters, polyorthoesters, polyanhydrides, polycarbonates, polyurethanes, polyamides and polyalkylene oxide, and combinations thereof.

8. A screw according to claim 1 wherein said instrument interface comprises an open area in said interface having a cross-sectional shape selected from the group consisting of a hex, an oval, a slotted square, a tapered square, a cruciform, a cross, and a star.

9. A screw according to claim 1 further comprising at least one of platelet rich plasma, concentrated bone marrow aspirate and lipoaspirate cells.

10. A screw according to claim 9 wherein said at least one of the platelet rich plasma, concentrated bone marrow aspirate, and lipoaspirate cells are isolated by centrifugation.

11. A kit for surgical repair of an ACL, the kit comprising:

a drive tool; and

at least one interference screw comprising,

a bioabsorbable ceramic structure having a plurality of interconnected pores filled with a bioabsorbable polymer,

said interference screw having an elongated threaded body, the elongated threaded body having a proximal end, a distal end, a length, a thread, and a taper, the thread of the interference screw extending substantially along the entire length of the interference screw from said proximal end to said distal end,

the elongated threaded body having a hollowed area in the proximal end operable for engagement of said drive tool, said hollowed area reinforced with said bioabsorbable polymer.

12. A kit according to claim 11 further comprising at least one of a drill bit, a dilator, a tibia tunnel guide, a modular guide, a graft prep table, a bone coring instrument, a tibial reamer, an imprigment rod, a femoral aimer, an acorn reamer, a top, a washer, a guide wire, a dilator, a pull-through suture, and a pilot hole tool.

13. An interference screw comprising a substantially cylindrical ceramic body having a tapered end and a thread starting near said tapered end, the body further comprising:

a bioabsorbable ceramic scaffold having a plurality of interconnecting channels;

a first volume of a bioabsorbable polymer in a majority of said plurality of interconnecting channels; and

a tool engagement region that is reinforced with a second volume of said bioabsorbable polymer.

14. A screw according to claim 13 further comprising an autologous tissue filling a minority of said plurality of interconnecting channels including at least one of platelet rich plasma, concentrated bone marrow aspirate, and lipoaspirate cells.

15. A screw according to claim 13 wherein the tool engagement region is in a hollow area of said body and threads surround the exterior of the body from the tapered end to a substantially flat top, said top having a hole in communication with the hollow area.

16. A screw according to claim 13 wherein said tool engagement region has a cross-sectional area that has a shape selected from the group consisting of a hex, an oval, a slotted square, a tapered square, a cruciform, a cross, and a star.

17. A screw according to claim 13 wherein said interconnecting channels have a size of from about 350 microns to about 550 microns.

18. A screw according to claim 13 wherein said bioabsorbable ceramic scaffold and said bioabsorbable polymer are bioresorbable at different rates.

19. A screw according to claim 13 wherein said bioabsorbable ceramic scaffold and said bioabsorbable polymer are bioresorbable at the same rates.

20. A screw according to claim 13 wherein said bioabsorbable ceramic scaffold comprises a material selected from the group consisting of calcium phosphate, calcium carbonate, calcium oxide, calcium sulfate, hydroxyapatite, magnesium calcium phosphate, and combinations thereof.

21. A screw according to claim 13 wherein said bioabsorbable polymer is selected from the group consisting of aliphatic polyesters, polyorthoesters, polyanhydrides, polycarbonates, polyurethanes, polyamides and polyalkylene oxide, and combinations thereof.

22. A screw according to claim 13 further comprising at least one of platelet rich plasma, concentrated bone marrow aspirate, and lipoaspirate cells.

23. A screw according to claim 22 wherein said at least one of the platelet rich plasma, concentrated bone marrow aspirate, and lipoaspirate cells is isolated by centrifugation.

24. An implantable interference screw system for use in soft tissue repair, the screw comprising:

a substantially-cylindrical ceramic body having a tapered end, at least a portion of said body comprising a plurality of interconnected pores;

an instrument interface at the end of said body opposite to said tapered end with a first bioresorbable polymer structurally reinforcing said instrument interface and contained within a perimeter of said body;

a thread starting near said tapered end, and surrounding at least a portion of a surface of said body; and

a second bioresorbable polymer, other than the first bioresorbable polymer, filling at least a portion of said plurality of interconnected pores.

25. A system according to claim 24, wherein said instrument interface includes a hollowed region in an end of said body operable for engagement of an instrument.

26. A system according to claim 25, further comprising:

said instrument, wherein said instrument engages the reinforced hollowed region through a hole in the end of the body to transfer a torque from the said instrument to said thread.

27. A system according to claim 24, wherein said plurality of pores includes a first sub-plurality of the plurality of pores having a first size range from about 100 microns or less and a second sub-plurality of the plurality of pores having a second size range from about 100 μ

m or greater;

wherein the second bioresorbable polymer fills substantially only the second sub-plurality of the plurality of pores.

28. A system according to claim 24, wherein interstitial spaces are between the plurality of interconnected pores within said body.

29. A system according to claim 25 further comprising:

an autologous tissue filling a minority of said plurality of interconnecting pores;

wherein said autologous tissue is selected from a group consisting of platelet rich plasma, concentrated bone marrow aspirate, and lipoaspirate cells.