Medically Reviewed by Dr Wang Lushun What Is Avascular Necrosis (AVN)? Avascular necrosis, often called osteonecrosis, occurs once the blood offer to bone cells is disrupted, resulting in the death of bone tissue. It normally targets the hip joint, specially the femoral head–the upper “ball” portion of the femur (thigh https://www.theorthopaedicandpainpractice.com/what-is-avascular-necrosis-of-the-hip/?_gl=1*xbbxlb*_up*MQ..&gclid=Cj0KCQjwkt6aBhDKARIsAAyeLJ2krYJSOuy5mZksrNqH-VDjQwW1ScD49yD8BUWysDG6u6bJPCSbXVUaAuCPEALw_wcB