en جراحی زانو Knee surgery Background: An increased incidence of osteonecrosis of the femoral head (ONFH) has recently been observed in Iran, likely associated with the introduction of an illegal, steroid-containing opioid drug, Temgesic. The correlation of risk factors associated with the course of ONFH has yet to be determined. Hip,avascular necrosis,Smoking 0 0 http://jros.iums.ac.ir/browse.php?a_code=A-10-39-51&slc_lang=en&sid=1 Mansour Abolghasemian mabolghasemian@gmail.com 10031947532846004480 10031947532846004480 Yes Bone and Joint Reconstruction Research Center, Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran , IR Iran Mehdi Ramezan Shirazi 10031947532846004481 10031947532846004481 No Clinical Fellow of Paediatric Orthopaedic Surgery, Tehran University of Medical Sciences, Tehran, IR Iran Kaveh Gharanizadeh 10031947532846004482 10031947532846004482 No Bone and Joint Reconstruction Research Center, Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran , IR Iran Ali Yeganeh 10031947532846004483 10031947532846004483 No Bone and Joint Reconstruction Research Center, Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran , IR Iran Oleg Safir 10031947532846004484 10031947532846004484 No Division of Orthopedic Surgery, Mount Sinai Hospital, University of Toronto, Toronto, Canada Allan Edward Gross 10031947532846004485 10031947532846004485 No Division of Orthopedic Surgery, Mount Sinai Hospital, University of Toronto, Toronto, Canada Mohammad Taghi Ghazavi 10031947532846004486 10031947532846004486 No Bone and Joint Reconstruction Research Center, Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran , IR Iran