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By identifying the differences in stress distributions of the 2 types of liners, it may be possible to determine whether the elevated-rim liner is useful for reducing polyethylene wear. Our hypothesis was that the high stress area on the bearing surface would decrease when an elevated-rim polyethylene liner is used rather than a flat liner. 3, 4, 5) Nevertheless, no studies have compared flat and elevated-rim polyethylene liners in terms of stress distributions on the bearing surface of the liners. However, in cases of mild malalignment of the metal cup, the polyethylene insert may be changed from flat to elevated, with the metal cup preserved, to reduce polyethylene wear and prevent postoperative dislocation this procedure is also less invasive for patients. Significant malalignment of the metal cup requires removal of the metal cup, adjustment of the angle, and re-installation. In cementless THA revision, there are some cases where the metal cup has no looseness, but the polyethylene liner is worn down and progressive osteolysis is seen. 1, 2) One of the main causes for revision surgery is postoperative dislocation, and the use of elevated polyethylene liners can effectively correct the inclination of metal cups, thereby preventing future dislocations. Selection of the appropriate polyethylene liner affects the long-term stability after THA. Unlike in cemented total hip arthroplasty (THA), several types of polyethylene liners can be used in cementless THA.