Intercondylar component and fin attachment features for use in knee arthroplasty

Patent metadata

Field	Value
Publication number	US-2016008136-A1
Application number	US-201514749908-A
Country	US
Kind code	A1
Filing date	Jun 25, 2015
Priority date	Jul 8, 2014
Publication date	Jan 14, 2016
Grant date	—

Abstract

Tibial prosthesis having one or more fins for use in a total or unicompartmental knee athroplasty procedure are disclosed. The one or more fins can be adapted to fix a tibial prosthesis to the tibia and can engage with corresponding channels formed in the resected tibia. Additionally, intercondylar components and methods for use in a total or unicompartmental knee athroplasty procedure are disclosed. The intercondylar component can be integral with or attached to a baseplate configured for attachment to a partially resected proximal surface of the tibia that retains at least a portion of the intercondylar eminence and the anterior cruciate ligament (ACL) and/or the posterior cruciate ligament (PCL). Inner surfaces of the intercondylar component can be configured to engage with at least a portion of the intercondylar eminence remaining with the partially resected tibia. In an example, the intercondylar component or the one or more fins can be formed of a porous material, such as to facilitate bone growth.

First claim

The claimed invention is:

1 . A tibial implant configured for attachment to a tibia in a knee arthroplasty, the tibial implant comprising:
a baseplate configured for attachment to a partially resected proximal surface of the tibia and comprising:
a medial compartment;
a lateral compartment; and
an anterior bridge portion between the medial and lateral compartments such that a notch is formed between an inner surface of the medial compartment and an inner surface of the lateral compartment; and
an intercondylar component attachable to or integral with the baseplate, the intercondylar component comprising:
a medial portion configured to connect to the inner surface of the medial compartment;
a lateral portion configured to connect to the inner surface of the lateral compartment; and
an arcuate portion between the medial portion and the lateral portion and configured to connect to the bridge portion of the baseplate.

2 . The tibial implant of claim 1 , wherein the intercondylar component includes a porous structure.

3 . The tibial implant of claim 2 , wherein the porous structure includes tantalum.

4 . The tibial implant of claim 2 , wherein substantially an entirety of the intercondylar component is formed of a porous metal structure.

5 . The tibial implant of claim 1 , wherein the baseplate includes a first plate formed of a porous structure and a second plate formed of a metal or polymeric material.

6 . The tibial implant of claim 5 , wherein the intercondylar component is integral with the first plate.

7 . The tibial implant of claim 6 wherein the intercondylar component and the first plate are bondable to an underside of the second plate.

8 . The tibial implant of claim 1 , wherein the partially resected proximal surface of the tibia includes at least a portion of an intercondylar eminence of the tibia and at least one of the ACL and PCL, and the intercondylar component engages with the intercondylar eminence when the tibial implant is attached to the tibia.

9 . The tibial implant of claim 1 , wherein one or more openings are formed in one or both of the medial and lateral compartment of the baseplate, the one or more openings configured to receive a bone screw for securement of the tibial implant to the resected tibia.

10 . A tibial component configured for attachment to a tibial implant having an elongated cut-out extending from a posterior end toward an anterior end of the implant, the tibial component comprising:
a first elongated portion; a second elongated portion; and an arcuate portion between the first and second elongated portions, wherein outer surfaces of the first and second elongated portions and the arcuate portion are configured to connect to surfaces of the tibial implant that form the elongated cut-out, and wherein inner surfaces of at least a portion of the first and second elongated portions and the arcuate portion are configured to engage with at least a portion of an intercondylar eminence remaining after resecting a proximal surface of the tibia.

11 . The tibial component of claim 10 wherein the tibial component is formed of a porous metal.

12 . The tibial component of claim 11 wherein the porous metal is tantalum.

13 . The tibial component of claim 10 wherein the tibial component further comprises a porous plate and the first and second elongated portions and the arcuate portion are integral with or attachable to the porous plate.

14 . The tibial component of claim 13 wherein the porous plate corresponds in size and shape to the tibial implant.

15 . The tibial component of claim 13 wherein the tibial component is bondable to the tibial implant.

16 . A method of performing a knee arthroplasty, the method comprising:
partially resecting a proximal surface of a tibia, while retaining at least a portion of an intercondylar eminence of the tibia and at least one of the ACL and PCL; attaching a tibial implant to the resected proximal surface of the tibia, the tibial implant comprising:
a baseplate having an inferior surface configured to contact the resected proximal surface of the tibia, a medial compartment, a lateral compartment, and an anterior bridge portion connecting the medial and lateral compartments such that a cut-out is formed between inner surfaces of the medial and lateral compartments; and
an intercondylar component attachable to or integral with the baseplate and comprising:
a first elongated portion configured to connect to the inner surface of the medial compartment of the baseplate;
a second elongated portion configured to connect to the inner surface of the lateral compartment of the baseplate; and
an arcuate portion between the first and second elongated portions and configured to connect to the bridge portion of the baseplate; and

engaging the intercondylar component with at least a portion of the retained intercondylar eminence to promote bone ingrowth.

17 . The method of claim 16 wherein engaging the intercondylar component with at least a portion of the retained intercondylar eminence includes forming a first press fit between the first elongated portion of the intercondylar component and the intercondylar eminence at or near a posterior end of the tibia and forming a second press fit between the second elongated portion of the intercondylar component and the intercondylar eminence at or near the posterior end of the tibia.

18 . The method of claim 16 wherein partially resecting a proximal surface of the tibia comprises:
resecting the medial and lateral articular surfaces of the tibia such that at least a portion of the intercondylar eminence remains between a resected surface on the medial side of the tibia and a resected surface on the lateral side of the tibia; and
resecting an anterior surface of the tibia between the medial and lateral articular surfaces.

19 . The method of claim 18 wherein the remaining portion of the intercondylar eminence includes side walls forming an exterior surface of the intercondylar eminence having a size and shape configured to correspond with the first and second elongated portions and the arcuate portion of the intercondylar component.

20 . The method of claim 19 further comprising:
forming a groove in the side walls of the remaining portion of the intercondylar eminence such that the intercondylar component can be pressed into the groove upon engaging the intercondylar component with the intercondylar eminence.

21 . A tibial implant configured for attachment to a tibia in a unicompartmental knee arthroplasty, the tibial implant comprising:
a baseplate configured for attachment to a resected medial or lateral compartment of the tibia; and an intercondylar component attachable to or integral with the baseplate and comprising:
an inner surface configured to engage with an inner edge of the baseplate; and
an outer surface configured to engage with an intercondylar eminence of the tibia, wherein the intercondylar component is formed of a porous metal structure to promote bone ingrowth of the intercondylar eminence and the resected medial or lateral compartment of the tibia.

22 . The tibial implant of claim 21 wherein the baseplate includes a first plate formed of a porous metal structure and a second plate formed of a metal or polymeric material.

23 . The tibial implant of claim 22 wherein the intercondylar component is integral with the first plate, and the intercondylar component and the f

Assignees

• Zimmer Inc

Inventors

• Jones Nolan C
• Roberts Shanon N

Classifications

• A61F2002/30011

  differing in porosity · CPC title

• A61F2/389 Primary

  Tibial components (A61F2/3868 takes precedence) · CPC title

• A61F2002/30879

  Ribs · CPC title

• A61F2002/3092

  having an open-celled or open-pored structure · CPC title

• A61F2002/30884

  Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity · CPC title