One embodiment of the present invention relates to a prosthesis, comprisingan acetabular cup, wherein the cup has an open end and a closed end, wherein theopen end of the cup is defined by a nm and wherein the rim has an outer facing surface,at least one cavity disposed in the rim, wherein the cavity extends from a firstend of the cavity at the outer facing surface to a second end of the cavity that istowards the closed end of the cup, and wherein the cavity comprises an undercutat the second end of the cavity, a locking ring, and at least one tab extending fromthe locking ring, wherein the tab comprises a first leg and a second leg havinga separation therebetween, wherein each leg has a first end and a second end.
