Patient Specific Knee Alignment Guide And Associated Method

• US 20080161815A1
• Filed: 02/29/2008
• Published: 07/03/2008
• Est. Priority Date: 02/27/2006
• Status: Active Grant

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Metzger, Robert, Sheffer, Garrett A., Schoenefeld, Ryan J., Deming, Scott
• Granted Patent: US 8,282,646 B2
• Time in Patent Office: Days
• US Class Current: 606/87
• CPC Class Codes: A61B 17/154 for preparing bone for knee prosthesis
• CPC Class Codes: A61B 17/155 Cutting femur
• CPC Class Codes: A61B 17/157 Cutting tibia
• CPC Class Codes: A61B 17/175 for preparing the femur for hip prosthesis insertion
• CPC Class Codes: A61B 17/1764 for the knee
• CPC Class Codes: A61B 17/58 for osteosynthesis, e.g. bone plates, screws , setting implements or the like A61B17/14, A61B17/16 take precedence
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: A61B 2017/00911 for fields applied by a magnetic resonance imaging system
• CPC Class Codes: A61B 2017/0268 for the knee
• CPC Class Codes: A61B 2017/568 produced with shape and dimensions specific for an individual patient
• CPC Class Codes: A61B 2034/252 indicating steps of a surgical procedure
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61B 90/14 Fixators for body parts, e.g. skull clamps; Constructional details of fixators, e.g. pins

Abstract

An orthopedic apparatus including a patient-specific alignment guide attachable to a surface of a bone being prepared for receiving a prosthetic implant. The guide includes at least first and second components and a coupling mechanism connecting the first and second components to one another. The first component has a first bone engagement surface and the second component has a second bone engagement surface, the first and second bone engagement surfaces anatomically matching corresponding first and second portions of the surface of the bone. At least one of the first and second components defines at least one alignment formation.

Claims

1. An orthopedic apparatus comprising:

a patient-specific alignment guide attachable to a surface of a bone being prepared for receiving a prosthetic implant, the guide comprising at least first and second components, the first component having a first three-dimensional bone engagement surface and the second component having a second three-dimensional bone engagement surface, the first and second bone engagement surfaces anatomically matching corresponding first and second portions of the surface of the bone;

at least one alignment formation defined by at least one of the first and second components; and

a coupling mechanism connecting the first and second components to one another.

2. The orthopedic apparatus of claim 1, wherein the alignment formation defines a guiding bore.

3. The orthopedic apparatus of claim 1, wherein the coupling mechanism is a snap-fit or interlocking mechanism allowing complete separation of the first and second components.

4. The orthopedic apparatus of claim 1, wherein the coupling mechanism is a hinge allowing relative rotation between the first and second components.

5. An orthopedic apparatus comprising:

a patient-specific alignment guide including;

a first component having a first three dimensional surface engaging and conforming in shape to a patient'"'"'s first anatomical portion in three dimensions and having an alignment formation referencing a first axis; and

a second component coupled to the first component, the second component having a second three-dimensional surface engaging and conforming in shape to a second anatomical portion of the patient, the second component having an alignment formation referencing a second axis; and

a coupling mechanism interconnecting the first and second components.

6. The orthopedic apparatus of claim 5, wherein at least one of the first and second components includes an indicator feature associated with a corresponding landmark anatomic feature for guiding placement of the corresponding component.

7. The orthopedic apparatus of claim 6, wherein the anatomic feature is a protrusion extending from the corresponding component.

8. An orthopedic apparatus comprising:

a patient-specific alignment guide; and

an adjustment mechanism coupled to the alignment guide, the adjustment mechanism providing intra-operative rotational and translational drill guide adjustments.

9. The apparatus of claim 8, wherein the adjustment mechanism provides rotational adjustments in at least two orthogonal planes.

10. The apparatus of claim 8, wherein the adjustment mechanism includes a plurality of pairs of guiding apertures, each pair of guiding apertures defining a different orientation and position.

11. The apparatus of claim 8, wherein the adjustment mechanism includes a pair of enlarged guiding apertures, the pair of guiding apertures adapted for supporting a drill guide in a plurality of different orientations and positions.

12. The apparatus of claim 8, wherein the adjustment mechanism includes a rotational connector for a drill guide.

13. The apparatus of claim 8, wherein the rotational connector provides rotation in at least two orthogonal planes.

14. The apparatus of claim 8, wherein the adjustment mechanism includes a combined rotational and translational connector for a drill guide.

15. The apparatus of claim 8, wherein the patient specific alignment guide has a three-dimensional surface engageable with a joint surface and a guide surface couplable with a drill guide.

16. A method for balancing soft tissue in knee surgery, the method comprising:

attaching a patient-specific alignment guide to a joint surface;

tensioning the soft tissue in flexion or extension; and

balancing the soft tissue relative to the patient-specific guide.

17. The method of claim 16, wherein balancing the soft tissue relative to the patient-specific guide, includes balancing without intra-operative determination of a femoral head center.

18. The method of claim 17, wherein balancing the soft tissue relative to the patient-specific guide, includes balancing without intra-operative determination of a mechanical axis of the knee.

19. The method of claim 18, wherein tensioning and balancing includes tensioning and balancing with a balancing tensor positioned proximate to the patient-specific alignment guide.

20. The method of claim 18, further comprising measuring the flexion and extension gaps.

21. The method of claim 17, wherein attaching a patient-specific alignment guide to a joint surface includes nestingly mating a three-dimensional engaging surface of the alignment guide to a corresponding joint surface.

22. The method of claim 17, wherein balancing the soft tissue relative to the patient-specific guide includes balancing relative to a guide surface of the alignment guide, the guide surface having a known relationship with an anatomic axis of the joint.

23. A patient positioner comprising:

a first outer surface shaped to support a portion of a patient'"'"'s anatomy in a location and orientation determined for image scanning of the portion of the patient'"'"'s anatomy; and

at least one marker visible in image scanning, the image marker integrated with the positioner.

24. The positioner of claim 23, wherein the image marker is applied on a second outer surface of the positioner.

25. The positioner of claim 23, wherein the image marker is embedded in an interior portion of the positioner.

26. A manufacturing assemblage comprising:

a first patient specific alignment guide;

a second patient specific alignment guide; and

a connection arm coupled to the first alignment guide at a first connection end and to the second alignment guide at a second connection end, the connection arm retaining together the first and second alignment guides, the connection arm including frangible features.

27. The manufacturing assemblage of claim 26, wherein the connection arm includes a plurality of interconnected links.

28. The manufacturing assemblage of claim 26, wherein the frangible features are located adjacent the first and second connection ends.