A total hip arthroplasty is the removal of damaged areas of bone from the hip joint and replacement with an artificial ball and socket joint. The head of the femur (thighbone), which is shaped like a ball, is replaced with an artificial ball and stem. The stem fits into the thighbone and bone cement is usually used to fix the stem in place. The socket, which is part of the pelvis and shaped like a small bowl, is replaced with an artificial cup.
The hip is a “ball and socket” joint. The ball is formed by the head of the thighbone (femur) which fits snugly into the cup shaped bone in the pelvis (acetabulum). The bones are coated in cartilage, which acts as a cushion between the two bones and allows movement.
The aim of total hip replacement is to relieve pain and improve movement. Total hip replacements are usually performed for people who have arthritis that is getting worse and is no longer responding to other treatments.
The most common type of arthritis is osteo-arthritis, which happens with aging, congenital abnormality of the hip joint, or previous injury to the hip joint.