Stabilized total ankle prosthesis

Abstract

The present invention relates to a stabilized ankle prosthesis configured for use in patients with compromised soft tissue in the ankle. The prosthesis of the present invention is a two-component design comprising a stabilizing lip configured to constrain movement in the general direction of compromised soft tissue.

What is claimed is: 
     
         1 .- 20 . (canceled) 
     
     
         21 . An ankle prosthesis comprising:
 a tibial component configured for attachment to a tibia, comprising a body having at least one side and an attachment surface on a proximal portion, the at least one side tapers inwardly toward the attachment surface, the at least one side and the attachment surface of the body being adapted to fit a recess formed in a resected tibia, the tibial component having an articulation surface on a distal portion that is wider than the attachment surface; and   a talar component configured for attachment to a talus, comprising an attachment surface on a distal portion, an articulation surface on a proximal portion, and a raised surface on a medial portion, wherein the raised surface is configured to:   (i) be superior in relation to the articulation surface and   (ii) limit eversion, wherein the articulation surface of the talar component complements the articulation surface of the tibial component.   
     
     
         22 . The ankle prosthesis of  claim 21 , wherein the talar component further includes a second raised surface on a lateral portion, wherein the second raised surface is configured to be superior in relation to the articulation surface and is configured to limit inversion. 
     
     
         23 . The ankle prosthesis of  claim 21 , wherein the talar component includes a first raised surface on a posterior edge configured to be superior in relation to the articulation surface of the tibial component to limit posterior displacement of the tibial component, and the talar component includes a second raised surface on an anterior edge, wherein the second raised surface is configured to be superior in relation to the articulation surface of the tibial component to limit anterior displacement of the tibial component. 
     
     
         24 . The ankle prosthesis of  claim 21 , wherein the articulation surface of the tibial component comprises a first material and the articulation surface of the talar component comprises a second material, wherein the first and second material are different. 
     
     
         25 . The ankle prosthesis of  claim 21 , wherein the proximal portion of the tibial component is convex and shaped to fit a concave opening formed in the tibia. 
     
     
         26 . The ankle prosthesis of  claim 21 , wherein the articulation surface of the tibial component has a bicondylar contour. 
     
     
         27 . An ankle prosthesis comprising:
 a tibial component configured for attachment to a tibia, comprising a body having at least one side and an attachment surface on a proximal portion, the at least one side tapers inwardly toward the attachment surface, the at least one side and the attachment surface of the body being adapted to fit a recess formed in a resected tibia, the tibial component having an articulation surface on a distal portion that is wider than the attachment surface; and   a talar component configured for attachment to a talus, comprising an attachment surface on a distal portion, an articulation surface on a proximal portion, and a raised surface on a lateral portion wherein the raised surface is configured to (i) be superior in relation to the articulation surface and (ii) limit inversion, wherein the raised surface is configured to be superior in relation to the articulation surface and limit eversion.   
     
     
         28 . An ankle prosthesis comprising:
 a tibial component configured for attachment to a tibia, including an attachment surface on a proximal portion, an articulation surface on a distal portion, and at least one side extending between the proximal portion and the distal portion, the at least one side tapering inward toward the attachment surface, the at least one side and the attachment surface adapted to fit into a recess formed in a resected tibia, the articulation surface being wider than the attachment surface, a first surface located on a posterior edge configured to be superior in relation to the articulation surface and a second surface on an anterior edge configured to be superior in relation to the articulation surface;   a talar component having an attachment surface on a distal portion and an articulation surface on a proximal portion, wherein the articulation surface includes a medial portion and a lateral portion, the medial portion having a first convex contour, the lateral portion having a second convex contour, wherein a concave contour is located between the first and second convex contours;   wherein the articulation surface of the tibial component comprises a medial portion having a second concave contour and a lateral portion having a third concave contour such that a third convex contour may be located between the second and third concave contours, and the articulation surface of the talar component complements the articulation surface of the talar component.   
     
     
         29 . The ankle prosthesis of  claim 28 , wherein the tibial component includes a raised surface on the medial portion, and wherein the raised surface is configured to be superior in relation to the articulation surface and configured to limit eversion. 
     
     
         30 . The ankle prosthesis of  claim 28 , wherein the tibial component includes a raised surface on the lateral portion, and wherein the raised surface is configured to be superior in relation to the articulation surface of the tibial component and to limit inversion. 
     
     
         31 . The ankle prosthesis of  claim 29  or  30 , wherein the tibial component includes a raised surface on the medial portion, and wherein the raised surface on the medial portion is configured to be superior in relation to the articulation surface of the talar component to limit eversion, and the tibial component further includes a raised surface on the lateral portion, and wherein the raised surface on the lateral portion is configured to be superior in relation to the articulation surface of the talar component and is configured to limit inversion. 
     
     
         32 . The ankle prosthesis of  claim 29  or  30 , wherein the articulation surface of the tibial component is comprised of a first material and the articulation surface of the talar component is comprised of a second material, wherein the first and second material are different.