Acetabular cup with rotatable bearing member

A prosthetic hip implant system comprising:

• a prosthetic femoral component having a stem portion, a neck portion coupled to the stem portion and a part-spherical head coupled to the neck portion;
• an acetabular component comprising:
• a housing, the housing having a part-spherical inner bearing surface having an open end with a circumferential rim portion, the rim portion having a circumferential radially inwardly angled ramp portion;
• a bearing element having a part-spherical first outer bearing surface region engaging the part-spherical inner bearing surface of the housing, the bearing element having a part-spherical inner surface region having an open end for receiving the head of the femoral component, the part-spherical first outer surface region of the bearing element extending about a central axis of the inner surface open end, the central axis intersecting a pole of the part-spherical outer surface region and a center of rotation of the part-spherical first outer surface region, the bearing element having a second part-spherical outer surface region extending from adjacent the open end towards the pole, the first outer surface region extending further from a center of rotation of the part-spherical inner surface of the bearing element than the second part-spherical surface region and an angled ramp portion engagable with the housing angled ramp portion formed between the first and second part-spherical outer surface region.