Humeral component of a shoulder joint prosthesis

Abstract

A humeral component of a reverse shoulder prosthesis includes a stem part configured for location within the intramedullary cavity of the humerus, the stem part having a stem axis, an epiphyseal part connected to the elongate stem part and having a concave bearing surface defining an epiphyseal axis, and wherein the epiphyseal axis is offset posteriorly relative to the stem axis.

1 - 13 . (canceled) 
     
     
         14 . A humeral component of a reverse shoulder prosthesis, comprising:
 a. an elongate stem part for location within the intramedullary cavity of the humerus, the stem part having a proximal face; and   b. an epiphyseal part having (i) a concave bearing surface for articulation with the convex bearing surface of a glenoid component, (ii) an opposite distal face which is directed towards the proximal face of the stem part when the stem part and the epiphyseal parts are assembled, and (iii) a surface extending between the distal face and the concave bearing surface;   wherein the elongate stem part defines a stem axis and the concave bearing surface of the epiphyseal part defines an epiphyseal axis, and in which one of the distal face of the epiphyseal part and the proximal face of the stem part carries a spigot connection feature and the other of the distal face of the epiphyseal part and the proximal face of the stem part carries a socket connection feature in which the spigot connection feature can be received so that the epiphyseal part and the stem part can be assembled with one another, the connection feature on the epiphyseal part being offset relative to the epiphyseal axis so that the epiphyseal axis in the assembled humeral component is offset posteriorly relative to the stem axis;   wherein the surface of the epiphyseal part which extends between the distal face and the concave bearing surface is adapted to contact bone tissue and to be positioned within the cortical tissue of the humerus.   
     
     
         15 . The humeral component as claimed in  claim 14 , wherein the distance between the stem axis and the epiphyseal axis is at least about 1.5 mm. 
     
     
         16 . The humeral component as claimed in  claim 14 , wherein the distance between the stem axis and the epiphyseal axis is not more than about 7 mm. 
     
     
         17 . The humeral component as claimed in  claim 14 , wherein the epiphyseal part comprises a shell part which defines a recess, and a bearing part which can be received in the shell part and which provides the bearing surface for articulation with a glenoid component. 
     
     
         18 . The humeral component as claimed in  claim 17 , wherein the rim of the shell part is approximately circular. 
     
     
         19 . The humeral component as claimed in  claim 17 , wherein the rim of the shell part is approximately planar. 
     
     
         20 . The humeral component as claimed in  claim 19 , wherein the plane defined by the rim of the shell part is approximately perpendicular to the epiphyseal axis. 
     
     
         21 . The humeral component as claimed in  claim 14 , wherein the angle between the stem axis and the epiphyseal axis, when viewed along the anterior-posterior axis, is at least about 20°. 
     
     
         22 . The humeral component as claimed in  claim 14 , wherein the angle between the stem axis and the epiphyseal axis, when viewed along the anterior-posterior axis, is not more than about 35°.