Continuous phase compositions for ACL repair

• US 9,211,184 B2
• Filed: 08/01/2013
• Issued: 12/15/2015
• 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): BATES, DAVID W
• Application Number:
  US13/956,948
• Publication Number:
  US 20130317612A1
• Time in Patent Office: 866 Days
• Field of Search: 606/321
• US Class Current: 1/1
• 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, resorptive for implantable prostheses A61F2210/0004
• 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. A method of fixation of a ligament for ACL reconstruction using a bioabsorbable interference screw comprising a bioabsorbable structure material, the bioabsorbable interface screw having a composite portion and a tool engagement area coupled to a proximal end thereof;

the composite area including;

a plurality of interconnecting pores formed in a ceramic structure,

a volume of bioresorbable polymer filling at least a portion of said plurality of interconnecting pores in the ceramic structure, and

an elongated threaded body having the proximal end, distal end, a length between the proximal end and the distal end, and a taper along the length, wherein the threaded body includes threads along the length and the taper extends along substantially the entire length of said bioabsorbable interference screw from said proximal end to said distal end;

the tool engagement area comprising a second volume of the bioresorbable polymer, the tool engagement area being configured to engage with a tool for engaging the threads of the screw to a wall of a tunnel;

said method comprising;

forming the tunnel in a femur, said tunnel having the wall;

inserting a ligament in said tunnel and inserting said bioabsorbable interference screw into the tunnel such that said elongated threaded body fills at least a portion of said tunnel;

engaging said threads at the proximal end of said bioabsorbable interference screw into cortical bone in said tunnel; and

securely affixing said ligament between said threads of said bioabsorbable interference screw and said wall of said tunnel.

2. The method according to claim 1 further comprising:

inserting a tool in an engagement area in said proximal end of said bioabsorbable interference screw, said engagement area reinforced with a bioresorbable polymer; and

driving said screw into said wall of said tunnel.

3. The method according to claim 1 further comprising:

forming a second tunnel in a tibia, said second tunnel having a wall;

inserting said ligament in said second tunnel;

pulling said ligament with a known force;

inserting a second bioabsorbable interference screw into said second tunnel, said second bioabsorbable interference screw having threads and a proximinal end, wherein said threads of said proximal end of said second bioabsorbable interference screw engage bone in the second tunnel; and

securely affixing said ligament between said threads of said second bioabsorbable interference screw and said walls of said second tunnel.

4. The method of claim 2, wherein:

said bioabsorbable interference screw has a composite portion and said engagement area; and

said composite portion includes said plurality of interconnecting pores formed in a ceramic structure and said bioresorbable polymer filling at least said portion of said plurality of interconnecting pores in said ceramic structure.

5. The method of claim 4, wherein said bioresorbable polymer of said engagement area is the same as said bioresorbable polymer filling at least said portion of said plurality of interconnecting pores in said ceramic structure.

6. The method of claim 1, wherein:

said composite portion has at least a sub-plurality of pores of said plurality of interconnecting pores formed in said ceramic structure, each having an entrance and an exit on a surface of the composite portion.

7. The method of claim 1, wherein said composite portion has a microporosity and a macroporosity, wherein the microporosity diameter is smaller than the macroporosity diameter.

8. The method of claim 7, wherein substantially only the macroporosity is filled with said bioresorbable polymer.

9. The method of claim 8, wherein said ceramic structure is formed of said bioabsorbable structure material.

10. A method of fixation of a ligament for ACL reconstruction, comprising:

forming a tunnel in a femur, said tunnel having a wall;

inserting a ligament in said tunnel;

selecting a bioabsorbable interference screw having a tool engagement area molded to a proximal end of a composite area, said composite area having a bioabsorbable structure material with a plurality of interconnecting pores and a first volume of a bioresorbable polymer filling at least a portion of said plurality of interconnecting pores, said composite area of the bioabsorbable interference screw having an elongated threaded body with threads, the proximal end, a distal end, an entire length from said proximal end to said distal end, and a taper, said threads and said taper of said bioabsorbable interference screw extending along substantially said entire length of said bioabsorbable interference screw;

inserting a tool in said tool engagement area in said proximal end, said tool engagement area reinforced with a second volume of said bioresorbable polymer;

driving said screw into said tunnel with the tool, wherein said elongated threaded body fills at least a portion of said formed tunnel; and

securely affixing said ligament between said threads of said bioabsorbable interference screw and said wall of said tunnel.

11. The method of claim 10, further comprising:

driving said bioabsorbable interference screw into said wall of said tunnel; and

engaging at least a portion of said threads into cortical bone at said wall of said tunnel.

12. The method of claim 11, wherein said bioabsorbable structure material is a ceramic material.

13. The method of claim 12, wherein:

said composite area has at least a sub-plurality of pores of said plurality of interconnecting pores, each having an entrance and an exit on a surface of the composite area; and

said ceramic material includes said plurality of interconnecting pores.

14. The method of claim 13, wherein selecting said composite area has a microporosity and a macroporosity, and the microporosity diameter of said microporosity is smaller than the macroporosity diameter of said macroporosity.

15. The method of claim 14, wherein substantially only said macroporosity to be filled with said bioresorbable polymer.

16. The method according to claim 15, further comprising:

forming a second tunnel in a tibia, said second tunnel having a wall;

inserting said ligament in said second tunnel;

pulling said ligament with a known force;

inserting a second bioabsorbable interference screw into said second tunnel, threads of a proximal end of said second bioabsorbable interference screw engage bone in the second tunnel; and

securely affixing said ligament between said threads of said second bioabsorbable interference screw and said walls of said second tunnel.

17. A method of fixation of a ligament for ACL reconstruction, comprising:

forming a tunnel in a bone, said tunnel having a wall;

inserting a ligament in said tunnel;

selecting a bioabsorbable interference screw having a tool engagement area coupled to a composite area, said composite area having a bioabsorbable structure material with a plurality of interconnecting pores and a volume of bioresorbable polymer filling at least a portion of said plurality of interconnecting pores, wherein at least a sub-plurality of pores of said plurality of interconnecting pores each have an entrance and an exit on a surface of the composite area, further wherein said composite area includes a microporosity and a macroporosity and substantially only said macroporosity is filled with said bioresorbable polymer;

inserting a tool in said tool engagement area in said proximal end, said tool engagement area reinforced with a second volume of said bioresorbable polymer;

driving said screw into said tunnel using the tool; and

securely affixing said ligament between said threads of said bioabsorbable interference screw and said wall of said tunnel.

18. The method of claim 17, wherein securely affixing said ligament includes said bioabsorbable interference screw body filling at least a portion of said formed tunnel.

19. The method of claim 17, wherein a microporosity diameter of the microporosity is smaller than a macroporosity diameter of the macroporosity.