Patent ID: 8192498
Filing Date: 2012-06-05
Classification: A61F

Abstract:
1. An orthopaedic knee prosthesis comprising: a femoral component having a condyle surface that is curved in the sagittal plane; and a tibial bearing having a bearing surface configured to articulate with the condyle surface of the femoral component, wherein the condyle surface (i) contacts the bearing surface at a first contact point on the condyle surface at a first degree of flexion, the first degree of flexion being less than about 30 degrees, (ii) contacts the bearing surface at a second contact point on the condyle surface at a second degree of flexion, the second degree of flexion being in the range of 45 degrees to 90 degrees, and (iii) contacts the bearing surface at a plurality of contact points between the first contact point and the second contact point when the femoral component is moved from the first degree of flexion to the second degree of flexion, each contact point of the plurality of contact points being defined by a ray extending from a common origin to the respective contact point of the plurality of contact points, each ray having a length different from every other ray such that a curved surface section having a non-constant radius of curvature is defined between the first contact point and the second contact point, wherein (i) the condyle surface has a first radius of curvature in the sagittal plane at the first contact point, the first radius of curvature having an origin, (ii) the condyle surface has a second radius of curvature in the sagittal plane at the second contact point, and (iii) the ratio of the first radius of curvature to the second radius of curvature is in the range of 1.10 to 1.45, and (iv) the distance between the origin of the first radius of curvature and the common origin of the rays is in the range of 0 and 10 millimeters.