Acetabular implant alignment devices and methods

Patent metadata

Field	Value
Publication number	US-11173045-B2
Application number	US-201916575871-A
Country	US
Kind code	B2
Filing date	Sep 19, 2019
Priority date	Apr 26, 2013
Publication date	Nov 16, 2021
Grant date	Nov 16, 2021

Abstract

A trial medical instrument for aligning an acetabular component, comprising: a first portion configured to fit within a patient's acetabulum; and a second portion extending from the first portion; wherein the second portion extends from the first portion in a direction that mimics a shape formed by a femoral implant component coupled with an acetabular implant component when a femur to which the femoral implant component is coupled is in a position relative to an acetabulum to which the acetabular implant component is coupled that is near an extent of a typical range of motion of the femur. As used herein, the phrase “extent of a typical range of motion” describes typical angular displacements of a femur as usually limited by patient anatomy.

First claim

The invention claimed is:

1. A medical instrument for aligning an acetabular component within a patient's acetabulum, the medical instrument comprising:
a femoral interface arranged and configured to couple with a patient's femur to align the medical instrument in a predetermined relationship with the femur;
an acetabular interface configured to be positioned within the acetabulum to indicate a position for placement of the acetabular component within the acetabulum, the acetabular interface includes indicia;
a body coupled between the femoral interface and the acetabular interface, wherein the body orients the acetabular interface in a fixed relationship with the femoral interface; and
a guide coupled to the body, the guide being arranged and configured to implant a reference pin into bone to establish and maintain a relative position for the acetabular component relative to the bone;
wherein the fixed relationship of the acetabular interface relative to the femoral interface is substantially the same as the relationship between the acetabular component and a femoral component where the femur that is configured to be coupled with the femoral component is in a position relative to the acetabulum.

2. The medical instrument of claim 1 , wherein the femoral interface includes an intramedullary component to couple with a medullary canal of the femur.

3. The medical instrument of claim 1 , wherein the acetabular interface is at least in part spherical.

4. The medical instrument of claim 1 , wherein the indicia provides a reference for marking the acetabulum to receive the acetabular component.

5. The medical instrument of claim 1 , wherein the indicia provides a reference for determining a size and an orientation of the acetabular interface relative to the acetabulum.

6. The medical instrument of claim 1 , wherein the acetabular interface is configured to be positioned within a reamed acetabulum.

7. The medical instrument of claim 1 , wherein the acetabular interface is configured to be positioned within an unreamed acetabulum.

8. The medical instrument of claim 1 , wherein the guide is movably positionable relative to the body.

9. The medical instrument of claim 1 , wherein the guide includes a plurality of openings for positioning a reference pin.

10. The medical instrument of claim 1 , further comprising a reference pin, wherein the reference pin is arranged and configured to provide a reference position to align an axis of an acetabular reamer.

11. The medical instrument of claim 1 , further comprising a reference pin, wherein the reference pin is inserted along a trajectory into the bone to establish and maintain a relative position of an acetabular component relative to the bone.

12. The medical instrument of claim 1 , further comprising a reference pin, wherein the reference pin is configured to mark a desired position of the acetabular interface relative to the acetabulum.

13. The medical instrument of claim 1 , wherein the indicia is etched into a surface of the acetabular interface that is configured to face the acetabulum, wherein the indicia are configured to provide a reference for alignment relative to the acetabulum.

14. The medical instrument of claim 1 , wherein the femoral interface, the acetabular interface, and the body are arranged and configured to mimic a combined shape of a femoral hip replacement component designed to articulate with an acetabular hip replacement component, wherein the shape that is mimicked is the combined shape of the femoral hip replacement component and the acetabular hip replacement component when a femur that is configured to be coupled with the femoral component is in a position relative to the acetabulum.

15. The medical instrument of claim 1 , wherein the acetabular interface and the body are a single piece and the femoral interface is configured to removably affix to the body.

16. The medical instrument of claim 1 , wherein the femoral interface and the body are a single piece and the acetabular interface is configured to removably affix to the body.

17. The medical instrument of claim 1 , wherein the acetabular interface, the body, and the femoral interface are a single piece.

18. A method of aligning and implanting an acetabular component into a patient's acetabulum comprising:
providing a medical instrument for aligning the acetabular component, the medical instrument comprising:
a femoral interface configured to couple with a femur to align the medical instrument in a predetermined relationship with the femur;
an acetabular interface configured to be positioned within the acetabulum to indicate a position for placement of the acetabular component within the acetabulum, the acetabular interface includes indicia;
a body coupled between the femoral interface and the acetabular interface, wherein the body orients the acetabular interface in a fixed relationship with the femoral interface; and
a guide coupled to the body, the guide configured to place one of a fastener or a reference pin into bone to establish and maintain a relative position for the acetabular component relative to the bone;

coupling the femoral interface of the medical instrument to the femur to align the medical instrument in a predetermined relationship with the femur;
recording a position of the acetabular interface relative to the acetabulum via inserting one of a fastener or a reference pin through the guide and into the patient's bone in or near the acetabulum; and
implanting the acetabular component based on the recorded position of the acetabular interface relative to the acetabulum.

19. The method of claim 18 , wherein inserting one of a fastener or a reference pin through the guide and into the patient's bone in or near the acetabulum includes implanting the fastener or reference pin parallel to an axis defined by a center of the acetabulum.

20. The method of claim 18 , wherein inserting one of a fastener or a reference pin through the guide and into the patient's bone in or near the acetabulum includes implanting the fastener or reference pin at an angle offset from an axis defined by a center of the acetabulum.

21. The method of claim 18 , wherein the act of recording a position of the acetabular interface relative to the acetabulum further comprises marking the acetabulum.

22. The method of claim 21 , wherein marking the acetabulum comprises utilizing the indicia on a surface of the acetabular interface facing the acetabulum to mark locations on the acetabulum at which the indicia intersect edges of the acetabulum.

23. The method of claim 22 , wherein implanting the acetabular component comprises utilizing the indicia on a surface of the acetabular component facing the acetabulum to align the indicia on the acetabular component relative to the marked locations.

24. The method of claim 21 , wherein marking the acetabulum comprises marking locations at which a rim of the acetabular interface intersects edges of the acetabulum.

25. The method of claim 18 , further comprising reaming the acetabulum, wherein the reamer is coupled to the fastener or reference pin.

Assignees

• Smith & Nephew Inc

Inventors

• Kelman David C
• Clausen John
• Elliott M Scott
• Evans David L
• Belew Kevin W
• Rister David W
• Frederick Phillip E
• Walter Russell

Classifications

• A61F2/34 Primary

  Acetabular cups · CPC title

• A61F2/32

  for the hip · CPC title

• A61F2/4609 Primary

  of acetabular cups · CPC title

• A61F2/4684

  Trial or dummy prostheses · CPC title

• A61B17/1746

  for the acetabulum · CPC title