A prosthesis comprising: a humeral stem; a humeral cup; and, a variable angle tray coupled to the humeral stem and the humeral cup, the variable angle tray comprising: a plate including an arcuate wall at least partially defines an internal cavity, a bearing adapted to occupy at least a portion of the internal cavity, the bearing being axially and rotationally repositionable with respect to the plate, the bearing operative to selectively expand in at least one dimension to wedge the bearing against the arcuate wall to inhibit axial and rotational repositioning of the bearing with respect to the plate, and a projection adapted to be coupled to the bearing, the projection also adapted to be coupled to the humeral stem in order to mount the variable angle tray to the humeral stem, where the arcuate wall is sized to retain a portion of the bearing within the internal cavity.