<prompt> Most common cause of AVN of the hip isIdiopathicAlcoholismCaissons DiseaseFracture neck of femur  <response>: Answer- A. IdiopathicCauses ofAVN hipldiopathic most commonInfection- septic ahritis, osteomyelitisHematological malignancies- leukemia, lymphomaAlcohol,coicosteroidsSLEPregnancyCassions diseaseHyperlipidemiaPehes diseasIonising radiation 