Hip socket bone grafting. Diagram showing the first stage in hip socket bone grafting as part of a total hip replacement operation. Here, a metal mesh liner is placed in the acetabulum (hip socket) in the patient's pelvis to provide a solid base for the bone graft. Defects in the bone are filled with vigorously impacted morsellised cancellous bone. This is followed by cementing of the socket implant (acetabular cup) into which the 'ball' of the femoral implant (not shown) fits. For a sequence showing the process, see images C016/6783 to C016/6786.