Provisional tibial prosthesis system

摘要

The present disclosure provides a provisional tibial prosthesis system for a set of prosthetic knee joints for implantation in a natural knee, the provisional tibial prosthesis system including a bearing component and a bearing support, the spacing of the bearing component from the bearing support is adjustable to allow for representation of a variety of different sized final tibial prostheses. In this system, only one provisional bearing component corresponding to each level of constraint is needed and shims are used to adjust the spacing of the bearing component from the bearing support. The shims are slidably insertable between the bearing component and the bearing support in an anterior/posterior direction to allow for adjustment of the spacing of the bearing component from the bearing support. The number of provisional components needed during knee surgery is reduced and adjustment of the system only requires the knee joint to be distracted by a distance equal to the height of a particular shim.

主权项

1. A tibial prosthesis system for implantation on a resected surface of a proximal tibia, the tibial prosthesis system comprising:
a bearing component having a superior articulating surface and an inferior surface; a base component having a superior surface and an inferior surface, the superior surface having a feature configured to mate with a corresponding second feature on the inferior surface of the bearing component, the feature and the second feature configured to allow the bearing component to be movable relative to the base component in a proximal/distal direction and the feature and the second feature configured to prevent significant relative movement between the bearing component and the base component in a medial/lateral direction and an anterior/posterior direction; a shim component configured to be removably received between the inferior surface of the bearing component and the superior surface of the base component by insertion of the shim component therebetween, the insertion of the shim component changes a relative proximal/distal position between the inferior surface of the bearing component and the superior surface of the base component; and a tibial baseplate having a bone contacting surface adapted to interface with the resected surface of the proximal tibia and an opposing baseplate superior surface, wherein the base component is configured to be coupled to the tibial baseplate.