Prosthetic knee implant

Patent metadata

Field	Value
Publication number	US-9351842-B2
Application number	US-201414201240-A
Country	US
Kind code	B2
Filing date	Mar 7, 2014
Priority date	Mar 14, 2013
Publication date	May 31, 2016
Grant date	May 31, 2016

Abstract

Knee implant systems and methods for implantation or use in a knee joint, are disclosed. A knee implant system can include at femoral component having a femur-contacting surface and an opposing articulation surface, and proximal, distal, anterior and posterior portion. The femoral component can include a medial condyle and a lateral condyle, where each of the condyles define respective distal-most points and have substantially equal widths. The width of each of the condyles can define respective condyle midpoints, where the distal-most points can be located laterally from the midpoints. The femoral component can include a trochlear groove that can define a distal-most sulcus point located halfway between the distal-most point of the medial condyle and the distal-most point of the lateral condyle.

First claim

What is claimed is:

1. A prosthetic knee implant, comprising:
a femoral component having a femur-contacting surface, an opposing articulation surface, and proximal, distal, anterior and posterior portions, the femoral component including:
a medial condyle and a lateral condyle, each of the condyles defining respective distal-most points and having substantially equal widths, as measured from a condyle medial side to a condyle lateral side and proximate the distal portion,
the width of each of the condyles defining respective condyle midpoints halfway between the condyle medial sides and the condyle lateral sides, the distal-most points located laterally from the midpoints; and
a trochlear groove, proximate the anterior portion, defining a distal-most sulcus point located halfway between the distal-most point of the medial condyle and the distal-most point of the lateral condyle.

2. The prosthetic knee implant of claim 1 , wherein the distal-most point of the medial condyle is located laterally at a first distance from the medial condyle midpoint and the distal-most point of the lateral condyle is located laterally at a second distance, equal to the first distance, from the lateral condyle midpoint.

3. The prosthetic knee implant of claim 2 , wherein the first distance and the second distance are between 1.0 millimeter and 4.0 millimeters, inclusive.

4. The prosthetic knee implant of claim 1 , wherein the trochlear groove defines a patellar axis, when viewed from an anterior side of the femoral component, oriented substantially perpendicular to a plane connecting the distal-most point of the medial condyle and the distal-most point of the lateral condyle.

5. The prosthetic knee implant of claim 1 , wherein the trochlear groove defines a patellar axis, when viewed from an anterior side of the femoral component, oriented substantially perpendicular to a plane connecting the medial condyle midpoint and the lateral condyle midpoint.

6. The prosthetic knee implant of claim 1 , wherein the width of each of the condyles is between 19 millimeters and 31 millimeters, inclusive.

7. The prosthetic knee implant of claim 1 , further comprising a box-like projection extending from the femur-contacting surface and located halfway between the medial condyle midpoint and the lateral condyle midpoint.

8. The prosthetic knee implant of claim 1 , further comprising a concave surface extending between the medial and lateral condyles, the concave surface defining a proximal-most point halfway between the medial condyle distal-most point and the lateral condyle distal-most point.

9. The prosthetic knee implant of claim 1 , further comprising a tibial component having a tibial-contacting surface, an opposing articulation surface, and proximal and distal portions.

10. The prosthetic knee implant of claim 9 , wherein the articulation surface includes:
a medial dished surface portion and a lateral dished surface portion, each of the dished surface portions defining respective distal-most points and widths, as measured from a surface portion medial side to a surface portion lateral side,
the width of each of the dished surface portions defining respective dished surface portion midpoints halfway between the surface portion medial sides and the surface portion lateral sides, the distal-most points located laterally from the midpoints.

11. The prosthetic knee implant of claim 10 , wherein the distal-most point of the medial dished surface portion is located laterally a third distance from the medial dished surface portion midpoint and the distal-most point of the lateral dished surface portion is located laterally a fourth distance, equal to the third distance, from the lateral dished surface portion midpoint.

12. The prosthetic knee implant of claim 11 , wherein the distal-most point of the medial condyle is located laterally at a first distance from the medial condyle midpoint and the distal-most point of the lateral condyle is located laterally at a second distance, equal to the first distance, from the lateral condyle midpoint, and wherein the first and second distances are equal to the third and fourth distances.

13. The prosthetic knee implant of claim 10 , wherein the medial dished surface portion and the lateral dished surface portion are asymmetrical, when viewed from a posterior side of the tibial component.

14. The prosthetic knee implant of claim 10 , wherein the medial dished surface portion and the lateral dished surface portion are symmetrical, when viewed from a posterior side of the tibial component.

15. The prosthetic knee implant of claim 10 , wherein the tibial component further comprises a tibial post extending from the articulation surface and located halfway between the medial dished surface portion midpoint and the lateral dished surface portion midpoint.

16. The prosthetic knee implant of claim 10 , wherein the articulation surface further comprises a convex ridge surface extending between the medial and lateral dished surface portions, the convex ridge surface defining a proximal-most point halfway between the medial dished surface portion midpoint and the lateral dished surface portion midpoint.

17. The prosthetic knee implant of claim 10 , wherein the tibial component includes a plate component, including the tibial-contacting surface, and a bearing component, including the articulation surface.

18. A method, comprising:
implanting a femoral component, of a prosthetic knee implant, having a femur-contacting surface and an opposing articulation surface onto a distal end of a resected femur, including establishing artificial medial and lateral condyles of equal width and having distal-most points located laterally from respective condyle midpoints, and further establishing an artificial trochlear groove defining a distal-most sulcus point located halfway between the distal-most points of the artificial medial condyle and the distal-most point of the lateral condyle; and
implanting a tibial component, of the prosthetic knee implant, having a tibial-contacting surface and an opposing articulation surface onto a proximal end of a resected tibia, including establishing artificial medial and lateral dished surface portions having distal-most points on the articulation surface located laterally from respective dished surface portion midpoints.

19. The method of claim 18 , wherein establishing artificial medial and lateral condyles having distal-most points located laterally from the respective condyle midpoints includes lateralizing the distal-most points between 1.0 millimeter and 4.0 millimeters, relative to the condyle midpoints.

20. The method of any one of claim 18 , wherein establishing the artificial trochlear groove includes lateralizing the distal-most sulcus point between 1.0 millimeter and 4.0 millimeters, relative to a position halfway between the condyle midpoints.

21. The method of any one of claim 18 , wherein establishing the artificial medial and lateral dished surface portions having distal-most points on the articulation surface located laterally from the respective dished surface portion midpoints includes lateralizing the distal-most points between 1.0 millimeter and 4.0 millimeters, relative to the dished surface portion midpoints.

22. The method of any one of claim 18 , wherein implanting the femoral component further includes establishing a box-like projection extending from the femur-contacting surface and located halfway between the medial condyle midpoint and the late

Assignees

• Zimmer Inc

Inventors

• Todd Dwight
• Stoller Alex
• Bobba Aravinda
• Kumar Harish

Classifications

• A61F2/3836 Primary

  Special connection between upper and lower leg, e.g. constrained · CPC title

• A61F2/389

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

• A61F2/3886

  for stabilising knees against anterior or lateral dislocations · CPC title

• A61F2/3859 Primary

  Femoral components · CPC title

• A61F2/38

  for elbows or knees · CPC title