PATIENT-SPECIFIC ACETABULAR GUIDES AND ASSOCIATED INSTRUMENTS

• US 20120226283A1
• Filed: 02/21/2012
• Published: 09/06/2012
• 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: Meridew, Jason D., Schoenefeld, Ryan J., Slone, W. Jason, Metzger, Robert, Lombardi, Adolph V., Nycz, Jeffrey H., Witt, Tyler D., Munsterman, Matthew D., Wolfe, Alexander P., Kabata, Tamon, Nairus, James G., Clohisy, John C.
• Granted Patent: US 9,339,278 B2
• Time in Patent Office: Days
• US Class Current: 606/81
• CPC Class Codes: A61B 17/1617 with mobile or detachable parts
• CPC Class Codes: A61B 17/1659 Surgical rasps, files, planes, or scrapers
• CPC Class Codes: A61B 17/1666 for the acetabulum
• CPC Class Codes: A61B 17/1735 for rasps or chisels
• CPC Class Codes: A61B 17/1746 for the acetabulum
• CPC Class Codes: A61B 2034/108 Computer aided selection or customisation of medical implants or cutting guides
• CPC Class Codes: A61B 2090/034 abutting on parts of the device itself
• CPC Class Codes: A61F 2/4609 of acetabular cups
• CPC Class Codes: A61F 2002/4687 Mechanical guides for implantation instruments
• CPC Class Codes: F04C 2270/041 Controlled or regulated

Abstract

A patient-specific acetabular guide can be used for preparing an acetabulum of a patient to receive an acetabular implant. The acetabular guide includes a patient-specific engagement surface designed to be complementary and mateable with a corresponding surface of the patient'"'"'s pelvic anatomy. The acetabular guide is designed during a pre-operative plan for the patient by a three-dimensional reconstruction of the anatomy of the patient using two-dimensional medical images. The patient-specific engagement surface has a first portion mateable with a portion of the acetabulum of the patient. The acetabular guide includes a guiding element that extends from the acetabular guide opposite to the first portion of engagement surface. The guiding element defines a bore designed to be oriented along an alignment axis for an acetabular implant when the acetabular guide is engaged to the acetabulum.

Claims

1. A method for reaming and preparing an acetabulum of a patient for an acetabular implant, the method comprising:

engaging an acetabular area of the patient with a complementary surface of a patient-specific acetabular guide;

supporting an alignment rod on a support device attached to the patient'"'"'s pelvis;

orienting the alignment rod to be parallel to an alignment axis for inserting the acetabular implant, the alignment axis determined during a preoperative plan of the patient and coinciding with a center axis of a guiding element of the acetabular guide;

drilling a pilot hole in the acetabulum through a bore of the guiding element along the center axis;

removing the acetabular guide;

guiding an alignment pin of a reamer in the pilot hole such that the alignment pin is parallel to the alignment rod; and

reaming the acetabulum.

2. The method of claim 1, further comprising using rotational and translational mechanisms of the support device to orient the alignment rod parallel to the alignment axis.

3. The method of claim 2, further comprising:

coupling a shaft of a guiding handle to the guiding element of the acetabular guide before removing the acetabular guide such that the shaft of the guiding handle is oriented along the alignment axis;

orienting the alignment rod parallel to the shaft of the guiding handle; and

removing the guiding handle.

4. The method of claim 3, further comprising engaging the shaft of the guiding handle with a connector of the support device for orienting the alignment rod parallel to the alignment axis before removing the guiding handle.

5. The method of claim 3, further comprising:

guiding a shaft of an inserter carrying an acetabular cup parallel to the alignment rod after removing the guiding handle;

engaging the shaft of the inserter with a connector of the support device for orienting the shaft of the inserter parallel to the alignment axis; and

inserting the acetabular cup in the acetabulum.

6. The method of claim 1, wherein drilling a pilot hole in the acetabulum through a bore of the guiding element includes using a drilling element having a stop at a predetermined position for preventing over drilling of the acetabulum.

7. The method of claim 1, further comprising mating a portion of an acetabular rim of the patient with a corresponding portion of the complementary surface of the patient-specific acetabular guide.

8. The method of claim 1, further comprising mating a portion of a transverse acetabular ligament of the patient with a corresponding portion of the complementary surface of the patient-specific acetabular guide.

9. A method for reaming and preparing an acetabulum of a patient for an acetabular implant, the method comprising:

engaging an acetabular area of the patient with a complementary surface of a patient-specific acetabular guide, the acetabular guide designed during a pre-operative plan from a reconstructed three-dimensional image of the patient'"'"'s anatomy;

drilling a pilot hole in the acetabulum through a bore of a guiding element of the acetabular guide along a patient-specific alignment axis determined by the guiding bore;

inserting first and second marker pins into an area outside the acetabulum of the patient through corresponding first and second marker elements of the acetabular guide;

removing the acetabular guide;

without removing the marker pins;

reaming the acetabulum;

inserting an acetabular cup in the reamed acetabulum;

sliding a secondary guide over the first and second marker pins; and

engaging a planar arcuate surface of the secondary guide to a complementary rim surface of the acetabular cup to align the acetabular cup to a position and orientation determined in the pre-operative plan.

10. The method of claim 9, wherein reaming the acetabulum comprises guiding an alignment pin of a reamer in the pilot hole.

11. The method of claim 9, wherein sliding a secondary guide over the first and second marker pins comprises passing the marker pins through complementarily located first and second guiding elements of the secondary guide.

12. The method of claim 9, wherein the secondary guide is designed during a pre-operative plan based on a three-dimensional reconstruction of the patient'"'"'s anatomy such that when the planar arcuate surface of the secondary guide contacts and engages the rim of the acetabular cup, the acetabular cup is positioned and oriented as determined by the pre-operative plan for the patient.

13. An acetabular guide comprising:

a patient-specific engagement surface designed to be complementary and mateable with a corresponding surface of the patient'"'"'s pelvic anatomy as determined during a pre-operative plan of the patient by a three-dimensional reconstruction of the anatomy of the patient using two-dimensional medical images, the patient-specific engagement surface having a first portion mateable with a portion of an acetabulum of the patient; and

a guiding element extending from the acetabular guide opposite to the first portion of engagement surface, the guiding element defining a bore designed to be oriented along an alignment axis for an acetabular implant when the acetabular guide is engaged to the acetabulum.

14. The acetabular guide of claim 13, wherein the engagement surface includes a second portion mateable with a portion of a rim of the acetabulum of the patient.

15. The acetabular guide of claim 13, wherein the engagement surface includes a second portion mateable with a portion of an acetabular fossa of the patient.

16. The acetabular guide of claim 13, wherein the engagement surface includes a second portion mateable with a portion of a transverse acetabular ligament of the patient.

17. The acetabular guide of claim 13, further comprising first and second marker elements extending from a portion of the acetabular guide outside the acetabulum of the patient, the marker elements defining corresponding first and second bores for guiding first and second marker pins into a bone portion of the patient.

18. The acetabular guide of claim 17 in a combination with a secondary guide, the secondary guide designed during the pre-operative plan to include first and second secondary marker elements complementary to the first and second marker elements of the acetabular guide for receiving the first and second marker pins when the first and second marker pins are attached to a bone portion of the patient.

19. The combination of claim 18, wherein the secondary guide includes a planar arcuate surface complementary to a rim of an acetabular cup, the planar arcuate surface designed during the pre-operative plan to orient the acetabular cup in a pre-planned orientation and location in the acetabulum relative to an alignment axis when the planar arcuate surface of the secondary guide engages the rim of the acetabular cup.

20. The acetabular guide of claim 13 in combination with:

a guiding handle removably attachable to the guiding element of the acetabular guide along the alignment axis; and

a support device attachable to a pelvic portion of the patient, the support device including a connector supporting an alignment rod, the connector removably engageable with a shaft of the guiding handle, the support device including rotational and translational mechanisms for orienting the alignment rod parallel to the shaft of the guiding handle and parallel to the alignment axis.

21. The combination of claim 20, further comprising an inserter for an acetabular cup, the inserter including a shaft engageable with the connector to orient the shaft along the alignment axis for inserting the acetabular cup into the acetabulum of the patient.

22. The acetabular guide of claim 13 in combination with a reamer for reaming the acetabulum for receiving an acetabular cup, the reamer including a guiding pin receivable in a pilot hole oriented along the alignment axis and drilled in the acetabulum through the bore of the guiding element.

23. The combination of claim 22, wherein the reamer includes a spring that biases the guiding pin and provides tactile feedback during reaming.

24. The combination of claim 22, wherein the reamer includes a plurality of removable arcuate blades.

25. The combination of claim 24, wherein each blade is attachable to a corresponding supporting element shaped as a spherical section, such that the supporting elements collectively form a surface corresponding to a shape of the acetabular cup.

26. The combination of claim 18, wherein the secondary guide includes a third guiding element, the third guiding element defining a bore designed to be oriented parallel to the alignment axis for the acetabular implant when the secondary guide is engaged to the acetabulum.

27. The combination of claim 26, wherein the third guiding element is offset relative to the first and second secondary marker elements of the secondary guide.

28. The combination of claim 26, further comprising:

an alignment pin receivable in the bore of the guiding element;

an adaptor mountable over the alignment pin; and

an acetabular inserter including a collar configured to engage the adaptor and orient a shaft of the acetabular inserter along the alignment axis.

29. The acetabular guide of claim 13, wherein the engagement surface includes an interior edge configured to be parallel and conforming to a portion of a transverse acetabular ligament of the patient.

30. The acetabular guide of claim 13 in combination with:

an acetabular cup inserter; and

an electronic positioner removable attached to the shaft of the acetabular inserter, the electronic positioner capable of indicating a predetermined orientation based on calibration with the acetabular guide.

32. The method of claim 30, further comprising:

receiving feedback from the electronic positioner for guiding the acetabular inserter along the alignment axis.

31. A method for preparing an acetabulum of a patient for an acetabular implant, the method comprising:

removably engaging an acetabular area of the patient with a complementary surface of a patient-specific acetabular guide, the acetabular guide having a guiding element oriented along a patient-specific alignment axis, the alignment axis determined during a preoperative plan of the patient for implant alignment;

removably coupling a shaft of an acetabular inserter to the guiding element of the acetabular guide such that the shaft of the acetabular inserter is oriented along the alignment axis;

removably attaching an electronic positioner to the shaft of the acetabular inserter, the electronic positioner capable of indicating a predetermined orientation;

calibrating the electronic positioner to identify the alignment axis as the predetermined orientation;

removing the acetabular guide and the acetabular inserter from the acetabulum;

guiding the shaft of the acetabular inserter with an acetabular implant thereon along the alignment axis using the electronic positioner; and

inserting the acetabular implant into the acetabulum of the patient.

33. The method of claim 31, wherein receiving feedback includes receiving visual feedback from LEDs of the electronic positioner.