Beyond cementless hemispherical sockets.

One of the major goals of acetabular revision is achieving stability. To achieve intimate contact between the implant and host bone, which is critical for stability since bone ingrowth requires the absence of micromotion, the implant must match the defect or be able to bridge the defect. Hemispherical sockets can achieve long-term implant fixation in acetabular defects that are not extensive, whereas structural allografts are associated with long-term failure and reliance on them dooms the implant to failure. Increasing bone loss requires the use of implants that may not be hemispherical, such as the Oblong Cup, or devices that bridge the defect such as an antiprotrusio cage or Triflange Cup.