Ischaemic necrosis, osteonecrosis and aseptic necrosis are synonyms for the same disease process.
Avascular necrosis (AVN) is a disease process that is characterised pathologically by bone marrow ischaemia and eventual death of trabecular bone. Radiological manifestations of AVN occur in the late stages of the disease as the bone attempts to repair itself. As bone repair occurs, weight bearing bone becomes mechanically weakened and flattened and may eventually collapse. This leads to debilitating pain and osteoarthritis.
Causes of Avascular Necrosis:
AVN has several causes. Loss of blood supply to the bone can be caused by an injury - post-traumatic avascular necrosis, or by certain risk factors - non-traumatic avascular necrosis e.g. steroids, excessive alcohol use or Caisson disease (found in deep sea divers and tunnel workers dus to poor decompression giving rise to bubbles of nitrogen in the blood which block capillaries causing necrosis).
Avascular necrosis of the femoral head
Avascular necrosis of the capitate
click on the hip xray to see other pictures of the hip and femur
