A system and method for placing a prosthetic acetabular cup within anacetabulum aredisclosed. The system may comprise an acetabular cup with an eccentric socket.Theacetabular cup may be substantially hemispherical with a cup rim and a portionof the cuprim removed defining a relief. The cup may accommodate a concentric liner inan eccentricposition. Screw apertures may be present on the periphery of the cup and thescrewtrajectories may converge toward the dome of the cup. The cup is attached to atool whichis offset relative to the cup because of the substantially eccentric socket.The relief, whenthe cup is secured to the acetabulum, is positioned substantially anterior andthe socket ispositioned more posterior to provide a more natural center of rotation of afemoral headwithin the socket. The first relief reduces impingement of the acetabular cupon soft tissue.
