what is osteonecrosis?
What Is Osteonecrosis? Osteonecrosis is a condition that develops as a consequence of temporary or permanent loss of blood supply to bone. The lack of blood supply to bone causes that part of the bone to die. The bone may collapse as it dies, and if the affected bone is near a joint, the joint surface can collapse. Osteonecrosis can affect any bone but most commonly affects the ends of the femur, upper arm bone, knees, shoulders, and ankles.