Increasing the breaking load of ceramic cup inserts for hip joint prostheses by a defined back side collision of the cup insert and acetabular cup

摘要

The invention relates to an acetabular cup (4) and a cup insert (3) for a hip joint prosthesis (12), wherein the cup insert (3) is coupled to the acetabular cup by means of a clamping cone (5) of a conical clamping device in the equatorial region (7) of the two components (3, 4) and, in the unloaded state of the cup insert (3), a gap (8) is provided between the two components (3, 4) below the clamping cone (5) to the pole (6), said gap being delimited by the radial contours of the two components (3, 4). In order to reduce the tensile stresses in the cup insert, the radial contours of the two components (3, 4) have identical geometric elements in the same order, starling front the lower cone end (9) to the pole (6), and tangential or substantially tangential transitions exist between the geometric elements.