Standard or customized knee implant with asymmetric femoral component and tibial offset

Patent metadata

Field	Value
Publication number	US-9956048-B2
Application number	US-201615144415-A
Country	US
Kind code	B2
Filing date	May 2, 2016
Priority date	Feb 24, 2009
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

Methods and devices are disclosed relating improved articular models, implant components, and related guide tools and procedures. In addition, methods and devices are disclosed relating articular models, implant components, and/or related guide tools and procedures that include one or more features derived from patient-data, for example, images of the patient's joint. The data can be used to create a model for analyzing a patient's joint and to devise and evaluate a course of corrective action. The data also can be used to create patient-adapted implant components and related tools and procedures.

First claim

What is claimed is:

1. A knee replacement implant for implantation in a knee joint of a patient, comprising:a knee replacement implant including a femoral implant for implantation on a femur of the patient and a tibial implant for implantation on a tibia of the patient, the femoral implant including a lateral condyle portion having a generally curved lateral condylar shape, and having an lateral bearing surface configured to articulate with the tibial implant when the tibial and femoral implants are implanted in the knee joint of the patient and an inner surface configured to abut one or more bone cut surfaces of a lateral condyle of a femur when the femoral implant is implanted in the knee joint of the patient, wherein the lateral condyle portion includes a lateral distal portion and a lateral posterior portion; and the femoral implant further including a medial condyle portion having a generally curved medial condylar shape and having a medial bearing surface configured to articulate with the tibial implant when the tibial and femoral implants are implanted in the knee joint of the patient and a second inner surface configured to abut one or more bone cut surfaces of a medial condyle of the femur when the femoral implant is implanted in the knee joint of the patient, wherein the medial condyle portion includes a medial distal portion and a medial posterior portion; and the medial distal portion of the medial condyle portion and the lateral distal portion of the lateral condyle portion each having substantially the same width measured in substantially the mediolateral direction and the medial posterior portion of the medial condyle portion being wider than the lateral posterior portion of the lateral condyle portion measured in substantially the mediolateral direction, and wherein the lateral posterior portion is narrower than the lateral distal portion of the lateral condyle portion.

2. The knee replacement implant of claim 1 , wherein the lateral condyle portion has a narrowed posterior lateral portion, such that the width of the lateral condyle portion measured in substantially the mediolateral direction narrows in a posterior part of the lateral condylar portion configured to avoid a soft tissue of the patient when the femoral implant is implanted in the patient.

3. The knee replacement implant of claim 1 , wherein the lateral condyle portion has a narrowed posterior lateral portion, such that the width of the lateral condyle portion measured in substantially the mediolateral direction includes at least one of a divot or a concavity or a taper in a posterior part of the lateral condylar portion configured to avoid a soft tissue of the patient when the femoral implant is implanted in the patient.

4. The knee replacement implant of claim 1 , wherein the lateral posterior portion includes a bone cut facet on the inner surface, and the medial posterior portion includes a bone cut facet on the second inner surface, and wherein the bone facet cuts are not coplanar.

5. The knee replacement implant of claim 1 , wherein the inner surface of the lateral posterior portion includes a lateral facet surface and the second inner surface of the medial posterior portion includes a corresponding medial facet surface, each of the later facet surface and the medial facet surface being substantially planar, and wherein the lateral facet surface is oriented in a different plane from the medial facet surface.

6. The knee replacement implant of claim 1 , wherein a thickness of the lateral posterior portion is less than a corresponding thickness of the medial posterior portion.

7. The knee replacement implant of claim 1 , further comprising a tibial implant including a lateral plateau portion with a lateral plateau bearing surface configured to articulate with the lateral bearing surface of the femoral implant when the tibial and femoral implants are implanted in the knee joint of the patient, a medial plateau portion with a medial plateau bearing surface configured to articulate with the medial bearing surface of the femoral implant when the tibial and femoral implants are implanted in the knee joint of the patient, and a bone-facing surface configured to abut a proximal end of a tibia of the patient when the tibial implant is implanted in the knee joint of the patient.

8. The knee replacement implant of claim 7 , wherein the medial plateau bearing surface is configured to be offset in a proximal direction relative to the lateral plateau bearing surface when the tibial implant is implanted in the patient.

9. The knee replacement implant of claim 7 , wherein the medial condyle portion includes a medial joint line in the posterior medial portion, and the lateral condyle portion includes a lateral joint line in the posterior lateral portion, and wherein the medial joint line and the lateral joint line are configured to be offset relative to each other in an axial direction when the tibial and femoral implants are implanted in the knee joint of the patient and the knee replacement implant is in a flexed position.

10. The knee replacement implant of claim 7 , wherein the medial condyle portion includes a medial joint line, and the lateral condyle portion includes a lateral joint line, and wherein the medial joint line and the lateral joint line are configured to be offset in a substantially sagittal plane when the femoral implant is implanted in the patient.

11. The knee replacement implant of claim 7 , wherein the lateral plateau portion has an average thickness that is greater than the thickness of the medial bearing portion.

12. The knee replacement implant of claim 7 , wherein the medial plateau bearing surface is configured to have a medial slope when the tibial implant is implanted in the patient and the lateral plateau bearing surface is configured to have a lateral slope when the tibial implant is implanted in the patient, wherein the medial slope does not equal the lateral slope.

13. The knee replacement implant of claim 7 , wherein the medial plateau bearing surface is configured to have a medial slope when the tibial implant is implanted in the patient and the lateral plateau bearing surface has a lateral slope when the tibial implant is implanted in the patient, wherein the lateral slope is greater than the medial slope.

14. The knee replacement implant of claim 1 , wherein the posterior portion of the medial condyle is configured to have a posterior offset relative to the posterior portion of the lateral condyle.

15. The knee replacement implant of claim 1 , wherein the medial condyle portion includes a distal facet surface that is flexed posteriorly relative to a distal plane of a femur of the patient when the knee replacement implant is implanted in the patient.

16. The knee replacement implant of claim 1 , wherein the lateral condyle portion includes a distal facet surface that is flexed posteriorly relative to a distal plane of a femur of the patient when the knee replacement implant is implanted in the patient.

17. The knee replacement implant of claim 1 , wherein the inner surface of the lateral condyle portion includes a set of facet surfaces, and wherein the set of facet surfaces is flexed posteriorly relative to a femur of the patient when the knee replacement implant is implanted in the patient.

18. The knee replacement implant of claim 17 , wherein the second inner surface of the medial condyle portion includes a set of facet surfaces, and wherein the set of facet surfaces is flexed posteriorly relative to a femur of the patient when the knee replacement implant is implanted in the pa

Assignees

• Conformis Inc

Inventors

• Bojarski Raymond A
• Chao Nam T
• Slamin John
• Lang Philipp
• Fitz Wolfgang
• Steines Daniel
• Minas Thomas

Classifications

• A61B17/157

  Cutting tibia · CPC title

• A61B17/1764

  for the knee · CPC title

• A61F2/5046

  for designing or making customized prostheses, e.g. using templates, finite-element analysis or CAD-CAM techniques · CPC title

• A61F2002/30324

  differing in thickness · CPC title

• A61F2/389 Primary

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