System and Method for Joint Resurface Repair

• US 20120271417A1
• Filed: 05/14/2012
• Published: 10/25/2012
• Est. Priority Date: 05/01/2000
• Status: Active Grant

• Current Assignee: Arthrosurface, Inc (Anika Therapeutics Incorporated)
• Original Assignee: Arthrosurface, Inc (Anika Therapeutics Incorporated)
• Inventors: Ek, Steven W.
• Granted Patent: US 8,864,827 B2
• Time in Patent Office: Days
• US Class Current: 623/14.12
• CPC Class Codes: A61B 17/1635 for grafts, harvesting or transplants
• CPC Class Codes: A61B 17/1764 for the knee
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2/30942 for designing or making customized prostheses, e.g. using templates, CT or NMR scans, finite-element analysis or CAD-CAM techniques
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/4657 Measuring instruments used for implanting artificial joints for surgical instruments A61B90/06
• CPC Class Codes: A61F 2002/30112 Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2002/30116 partial circles, i.e. circular segments
• CPC Class Codes: A61F 2002/30607 Kits of prosthetic parts to be assembled in various combinations for forming different prostheses
• CPC Class Codes: A61F 2002/3085 with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/3895 unicompartimental
• CPC Class Codes: A61F 2002/4658 for measuring dimensions, e.g. length
• CPC Class Codes: A61F 2002/4663 for measuring volumes or other three-dimensional shapes
• CPC Class Codes: A61F 2230/0004 Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2250/0062 Kits of prosthetic parts to be assembled in various combinations for forming different prostheses

Abstract

An implant comprising a first, second, and third segment wherein the second and third segments partially overlap the first segment and define a load bearing surface comprising an anterior-posterior (AP) curvature including at least two tangential curves of the portion of the articular surface of the femoral condyle, the tangential curves having different radii of curvature. A drill guide comprises a body portion including a first, second and third bushing spaced along the body portion to establish a first, second and third axes, respectively. Each axis may be substantially normal to the articular surface at three different points along a curvature of the articular surface comprising the two tangential curves. A measuring device comprises a housing defining a longitudinally passageway and an outrigger. A guide pin may be received in the longitudinal passageway and a measuring device determines how far the guide pin is in the passageway.

Claims

1. An implant for replacing a portion of an articular surface of a bone comprising:

at least a first and a second segments each comprising a truncated, generally arcuate perimeter corresponding to a first, and a second overlapping generally circular excision site formed in said articular surface, respectively, wherein said second segments partially overlap said first segment on a first end of said first segment, said first and said second segments comprise a bone contacting surface and a load bearing surface, said load bearing surface comprising curvature corresponding to a curvature of said replaced portion of said articular surface of said bone.

2. The implant of claim 1, wherein said bone contacting surface comprises a first mounting feature configured to secure said implant to said bone.

3. The implant of claim 2, wherein said bone facing surface of said first segment includes said first mounting feature.

4. The implant of claim 2, wherein said first mounting feature is configured to securely engage with a fastening element, said fastening element configured to be secured to said bone.

5. The implant of claim 4, wherein said fastening element includes a mounting screw.

6. The implant of claim 4, wherein said first mounting feature includes a tapered opening configured to engage with a tapered post of said fastening element.

7. The implant of claim 4, wherein said first mounting feature includes a tapered post configured to engage with a tapered opening of said fastening element.

8. The implant of claim 2, wherein said bone contacting surface further comprises a second mounting feature configured to secure said implant to said bone.

9. The implant of claim 8, wherein said second mounting feature includes a protrusion extending generally outwardly from said bone facing surface.

10. The implant of claim 2, wherein said bone facing surface of said first segment includes said first mounting feature and wherein said bone facing surface of said second segment includes said second mounting feature.

11. The implant of claim 34, wherein said bone facing surface of said third segment includes a third mounting feature.

12. The implant of claim 11, wherein said first, said second, and said third mounting features are axially aligned with said first, said second, and said third overlapping generally circular excision site formed in said articular surface, respectively.

13. The implant of claim 1, wherein said load bearing surface comprises an anterior-posterior (AP) curvature and a medial lateral (ML) curvature

14. The implant of claim 1, wherein said curvature of said load bearing surface comprises at least two tangential curves of said portion of said articular surface of said bone, said tangential curves having different radii of curvature.

34. The implant of claim 1, further comprising a third segment comprising a truncated, generally arcuate perimeter corresponding to a third generally circular excision site formed in said articular surface, said third generally circular excision site overlapping with said second generally circular excision site, wherein said third-segment partially overlaps said first segment on a second end of said first segment, said third-segment comprising a portion of said bone contacting surface and said load bearing surface.

15. A method of forming an implant for replacing a portion of an articular surface, said method comprising:

reaming a first portion of said articular surface to form a first generally circular excision site;

reaming a second portion of said articular surface to form a second generally circular excision site partially overlapping said first generally circular excision site; and

selecting an implant having first and second segments each comprising a truncated, generally arcuate perimeter corresponding to said first and second overlapping generally circular excision sites, respectively, wherein said second segment partially overlap said first segment on a first end of said first segment, said first and said second segments comprise a bone contacting surface and a load bearing surface, said load bearing surface comprising curvature corresponding to a curvature of said replaced portion of said articular surface of said bone.

16. The method of claim 35, further comprising a placing a drill guide onto said articular surface and establishing a plurality of axes in said articular surface corresponding to said second and said third excision sites using said drill guide.

17. The method of claim 16, wherein reaming said second and said third excision sites comprises advancing at least one reamer along said plurality of axes towards said articular surface, wherein said at least one reamer is rotated about said plurality of axes.

18. The method of claim 15, further comprising securing said implant to bone beneath said articular surface.

19. The method of claim 18, wherein securing said implant further comprises securing a fastening element into said bone and securing said implant to said fastening element.

20. The method of claim 19, wherein said fastening element comprises a screw, and wherein securing said fastening element into said bone further comprises advancing said screw into said bone.

21. The method of claim 19, wherein said implant and said fastening element are secured using a tapered frictional coupling.

35. The method claim 15, further comprising reaming a third portion of said articular surface to form a third generally circular excision site partially overlapping said first generally circular excision site on a second end of said first segment;

and

wherein said selecting further comprises selecting an implant having first, second, and second third segments each comprising a truncated, generally arcuate perimeter corresponding to said first, said second, and said second third overlapping generally circular excision sites, respectively.

22. A drill guide for establishing a plurality of axes in an articular surface, said drill guide comprising:

a body portion comprising a generally arcuate shaped interior surface, wherein at least a portion of said interior surface is configured to be disposed on at least a portion of said articular surface; and

first and second bushings spaced along a length of said body portion and configured to establish first and second axes, respectively, wherein each of said first and said second axes are configured to be substantially normal to said articular surface at two different points, respectively, along a curvature of said articular surface comprising at least two tangential curves, said tangential curves having different radii of curvature.

23. The drill guide of claim 36, wherein at least one of said first, said second and said third bushings are removably coupled to said body portion.

24. The drill guide of claim 36, wherein said second bushing is disposed along said body portion between said first and said third bushings, and wherein a first angle α

between said first axis and said second axis and a second angle β

between said second axis and said third axis are substantially symmetrical.

25. The drill guide of claim 22, wherein said second bushing extends generally outwardly from said interior surface of said body portion.

26. The drill guide of claim 25, wherein said second bushing comprises an outer diameter substantially corresponding to a diameter of hole formed in said articular surface.

27. The drill guide of claim 36, wherein said first and said third bushings extend generally outwardly from an exterior surface of said body portion.

36. The drill guide of claim 22, further comprising a third bushing spaced along a length of said body portion and configured to establish a third axis substantially normal to said articular surface at a third point along a curvature of said articular surface.

28. A device for measuring a portion of an articular surface of bone, said device comprising:

a housing defining a longitudinal passageway extending from an open distal end, said housing further comprising an outrigger extending generally outwardly proximate said distal end a predetermined distance Rr from a longitudinal axis of said longitudinal passageway;

a guide pin configured to be at least partially received in said longitudinal passageway of said housing; and

a measuring device configured to determine how far said guide pin is received in said passageway.

29. The device of claim 28, wherein said measuring device further comprises a guide window disposed on said housing, said guide window comprising a plurality of indicia representing said distance measurements.

30. The device of claim 29, wherein said a proximal end of said guide pin is configured to align with at least one of said plurality of indicia to determine said distance measurements.

31. The device of claim 28, wherein a distal end of said guide pin comprises threads configured to engage with said articular surface.

32. The device of claim 31, wherein a distal end of said guide pin further comprises a tap including at least one fluted region and at least one cutting edge, wherein said guide pin is self-tapping.

33. The device of claim 29, wherein said guide pin further comprises indicia disposed a predetermined distance from said distal-most end of said guide pin corresponding to an insertion depth of said guide pin into said articular surface.