Frontal X-Ray showing osteoarthritis of the left hip of a 60-year-old female patient. The spacing between the femoral head and the hip socket (acetabulum) has almost worn away completely. Osteoarthritis is a joint disease aggravated by mechanical stress. Symptoms include joint pain, stiffness and swelling. In severe cases, the hip joint will need to be surgically replaced. The scan also shows avascular necrosis (osteonecrosis) of the hip joint. Avascular necrosis is the death of bone tissue due to poor blood supply.