idiopathic osteonecrosis of the femoral head (EFO_1001930) is most common form of osteonecrosis, the death of bone tissue following microvascular injury. Osteonecrosis of the femoral head (ONFH) is a complex multifactorial disease that is associated with genetic predisposition and exposure to certain environmental factors. Various etiological factors, including the use of corticosteroids, alcohol abuse, sickle cell anemia, radiation and Gaucher disease, are known to be implicated in the development of secondary osteonecrosis.