Avascular Femoral Necrosis
The medial femoral circumflex artery, because it is the main supplier of blood to the femoral head and neck. The lateral femoral circumflex artery and foveal artery also supply the head and neck, but to a lesser degree.
Avascular femoral neck necrosis can be caused by a variety of factors, including trauma (such as femoral neck fracture), chronic alcohol overuse, chronic steroid use, and blood diseases such as sickle cell disease.
Learn more about diagnosis and treatment: https://www.ncbi.nlm.nih.gov/books/NBK546658/