TIBIAL BEARING COMPONENT FOR A KNEE PROSTHESIS WITH IMPROVED ARTICULAR CHARACTERISTICS

摘要

An orthopaedic knee prosthesis includes a tibial bearing component with surface features which operate to protect adjacent soft tissues of the natural knee throughout a wide range of flexion. More particularly, the tibial bearing component provides an anterior relief space disposed between the dished lateral and medial articular compartments, in which the relief space is convex as viewed from a sagittal perspective across the medial/lateral extent of the relief space.

主权项

1. A tibial bearing component for articulation with femoral condyles, the tibial bearing component defining a tibial bearing component coordinate system comprising:
a bearing component transverse plane extending along a medial/lateral direction and an anterior/posterior direction; a bearing component coronal plane extending along a proximal/distal direction and the medial/lateral direction, the bearing component coronal plane perpendicular to the bearing component transverse plane; and a bearing component sagittal plane extending along the anterior/posterior direction and the proximal/distal direction, the bearing component sagittal plane perpendicular to the bearing component transverse plane and the bearing component coronal plane, the tibial bearing component configured for connection to a tibial baseplate and comprising: an articular surface and an opposing distal surface, the distal surface parallel to the bearing component transverse plane and sized and shaped for attachment to a proximal portion of the tibial baseplate, the articular surface including medial and lateral articular compartments sized and shaped for articulation with the femoral condyles, the medial and lateral articular compartments separated from one another by the bearing component sagittal plane, the articular and distal surface bounded by a tibial bearing periphery, an anterior relief space situated at a medial/lateral location between the medial and lateral articular compartments to define a medial/lateral span, the anterior relief space situated adjacent to an anterior edge of the tibial bearing periphery and extending posteriorly from the anterior edge across an anterior/posterior span, and the medial/lateral span of the anterior relief space comprising a plurality of sagittal cross-sectional profiles each extending from a posterior edge of the anterior relief space to an anterior edge of the anterior relief space, the plurality of sagittal cross-sectional profiles comprising a central curve on the bearing component, a medial curve, and a lateral curve, the central curve defining a central curve radius, the medial and lateral curves defining a medial curve radius and a lateral curve radius, respectively, wherein the central curve radius is larger than the medial curve radius and larger than the lateral curve radius.