Expandable augment trial

• US 20050075736A1
• Filed: 10/03/2003
• Published: 04/07/2005
• Est. Priority Date: 10/03/2003
• Status: Active Grant

• Current Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Original Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Inventors: Collazo, Carlos E.
• Granted Patent: US 7,547,327 B2
• Time in Patent Office: Days
• US Class Current: 623/20.160
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/3886 for stabilising knees against anterior or lateral dislocations
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30736 Augments or augmentation pieces, e.g. wedges or blocks for bridging a bone defect

Abstract

An expandable trial augment, a trial including an augment and a method for using an expandable trial augment are provided. The trial augment is preferably biased to expand in at least one direction.

Claims

1. An orthopaedic trial augment comprising:

a first block;

an expansion member slidably associated with the first block so that that the trial is expandable in at least one direction.

2. The orthopaedic trial augment of claim 1, wherein the expansion member includes a second block.

3. The orthopaedic trial augment of claim 2, wherein the first and second blocks are biased such that the blocks expand in at least one direction.

4. The orthopaedic trial augment of claim 3, wherein a spring is associated with at least one of the blocks and configured to bias the blocks in opposite directions and expand of the trial.

5. The orthopaedic trial augment of claim 3, wherein one of the first or second blocks includes at least one channel and the other of the first or second blocks includes at least one complementary surface configured to provide sliding movement between the first and second blocks.

6. The orthopaedic trial augment of claim 3, wherein one of the first or second blocks is keyed to fit inside the other of the first or second blocks to permit sliding movement between the two blocks in at least one direction.

7. The orthopaedic trial augment of claim 6, wherein one of the first or second blocks includes at least a pair of grooves adapted to receive complementary surfaces on the other of the first or second blocks.

8. The orthopaedic trial augment of claim 7, wherein the trial expands in an anterior-posterior direction with respect to an orthopaedic trial.

9. The orthopaedic trial augment of claim 8, wherein the trial augment includes engagement surfaces configured to cooperate with at least one groove in an orthopaedic trial to secure the trial augment within the orthopaedic trial.

10. The orthopaedic trial augment of claim 9, further comprising a stop member to prevent the blocks from sliding apart.

11. The orthopaedic trial augment of claim 10, wherein the stop member includes a pin.

12. The orthopaedic trial augment of claim 1, wherein the trial augment is configured to be used with a femoral trial.

13. A surgical tray including an orthopaedic trial augment according to claim 1.

14. A surgical tray including an orthopaedic implant trial according to claim 12.

15. An orthopaedic trial implant comprising:

a main trial implant body having at least one surface configured to be in contact with a bone surface;

a recess in the main trial implant body adapted to receive a trial augment;

at least one engagement surface for securing a trial augment in the recess; and

an expandable trial augment biased to expand in at least one direction and configured to be received in the recess.

16. The orthopaedic trial implant of claim 15, wherein the expandable trial augment includes at least one edge surface configured to cooperate with the at least one engagement surface.

17. The orthopaedic trial implant of claim 16, wherein the expandable trial augment comprises a pair of slidingly engaged blocks having a spring disposed between the blocks so that the augment expands in at least one direction.

18. The orthopaedic trial implant of claim 17, wherein the blocks include keyed mating surfaces permitting sliding movement between the two blocks.

19. The orthopaedic trial implant of claim 15, wherein the engagement surface includes at least one groove formed in the main trial implant body.

20. A method of augmenting an orthopaedic trial implant comprising:

providing a trial implant having at least one recess and an engagement surface for a trial augment; and

inserting a trial augment in the recess, the trial augment being expandable in at least one direction.

21. The method of claim 20, wherein the trial implant includes at least a pair of engagement surfaces and the trial augment includes a pair of edge surfaces adapted to cooperate with the engagement surfaces.

22. The method of claim 21, wherein the trial augment is biased to expand to a maximum distance in at least one direction.

23. The method of claim 22, wherein the trial augment is compressed in the at least one direction prior inserting the trial augment in the recess.

24. The method of claim 23, wherein the trial augment is released after insertion in the recess, such that the trial augment expands and is secured in the recess between the engagement surfaces.

25. The method of claim 24, wherein the trial augment comprises a pair of blocks in slidable engagement and a spring biases the blocks in a manner to expand the trial augment in the at least one direction.

26. The method of claim 25, wherein the spring provides sufficient force to secure the block between the engagement surfaces.

27. A method of augmenting an orthopaedic trial implant comprising:

compressing an expandable trial augment;

inserting the compressed trial augment in a portion of the femoral trial; and

releasing the compressed trial augment so that the trial augment expands and is secured to the femoral trial.

28. The method of claim 27, wherein the trial augment expands in an anterior-posterior direction with respect to the implant.

29. The method of claim 28, wherein the trial augment includes at least one edge surface that cooperates with a groove in the trial implant to secure the augment to the trial implant.

30. The method of claim 27, wherein the expandable augment includes at least two portions biased apart.

31. The method of claim 30, wherein the two portions are biased apart by a spring.