Avascular necrosis is a condition that occurs when the blood supply to the femoral head is compromised, causing part of the bone of the femoral head to die.
Lack of blood supply can occur from a traumatic event, such as a fracture or dislocation, or from chronic medical conditions such as diabetes, prolonged steroid use and excessive tobacco or alcohol consumption. The lack of blood supply causes death of the bone cells of the femoral head and may eventually result in collapse of the bone.
Early diagnosed AVN, without femoral head collapse, may be treated arthroscopically. In more severe cases, a minimally-invasive hip replacement is the definitive treatment option.