 Rarely both sides are done in one operation, most times one side is done and allowed to heal before the other side is done.Unlike in most other hip joint operations, the head of the femur is not replaced, but is allowed to heal and develop its own fibrous scar tissue so that the joint is no longer bone-to-bone, a pseudoarthrosis (also called a "false joint").The neck of the femur is usually removed at the same time as the head.