Medically Reviewed by Dr Wang Lushun Exactly what is Avascular Necrosis (AVN)? Avascular necrosis, also referred to as osteonecrosis, takes place if the blood supply to bone cells is disrupted, bringing about the death of bone tissue. It frequently targets the hip joint, specially the femoral head–the upper “ball” part https://www.theorthopaedicandpainpractice.com/what-is-avascular-necrosis-of-the-hip/?_gl=1*xbbxlb*_up*MQ..&gclid=Cj0KCQjwkt6aBhDKARIsAAyeLJ2krYJSOuy5mZksrNqH-VDjQwW1ScD49yD8BUWysDG6u6bJPCSbXVUaAuCPEALw_wcB