The femoral head is the most common location for AVN to occur. Etiology of the avascular necrosis can be remembered by the following mnemonic:

GIVE INFARCTS

• Gaucher disease
• Idiopathic (Legg-Calvé-Perthes, Köhler, Chandler)
• Vasculitis (SLE, polyarteritis nodosa, rheumatoid arthritis)
• Environmental (frostbite, thermal injury)
• Irradiation
• Neoplasia (associated coagulopathy)
• Fat (prolonged corticosteroid use increases marrow)
• Alcoholism
• Renal failure and dialysis
• Caisson disease
• Trauma (femoral neck fracture, hip dislocation)
• Sickle cell disease