Hip arthroscopy and the surgical drapes applied. The next step is to insert a fine needle under x-ray guidance into the hip joint. This breaks the 'suction seal' of the joint and allows further distraction if necessary (see fig 4). The surgeon wishes to see the ball move out the socket by approximately 1 cm, so that access to the hip joint can be achieved with minimal risk of damage to the joint surfaces. Most surgeons will inject fluid into the joint at this stage, again to ensure that there is enough space between the ball and socket for safe instrument access.
Joint replacement to fill in the gap. Other forms of arthroplasty include "resection(al) arthroplasty", "resurfacing arthroplasty", "mold arthroplasty", "cup arthroplasty", and "silicone replacement arthroplasty". Osteotomy to restore or modify joint congruity is also a form of arthroplasty. In recent decades, the most successful and common form of arthroplasty is the surgical replacement of a joint or joint surface with a prosthesis. For example, a hip joint that is affected by osteoarthritis may be replaced entirely (total hip arthroplasty) with a prosthetic hip. This procedure involves replacing both the acetabulum (hip socket) and the head and neck of the femur. The purpose of