Tehran University of Medical Sciences Journal of Orthopedic and Spine Trauma 2538-2330 8 1 2022 04 13 1 4 Mir Mansour Moazen Jamshidi Department of Orthopedic Surgery, Hip and Pelvic Fellowship, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran Alireza Moharrami Joint Reconstruction Research Center, Tehran University of Medical Sciences Amir Hossein Poopak School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Amir Hossein Mafi Joint Reconstruction Research center, Department of Orthopedic Surgery, Imam Khomeini Hospital Complex, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Amir Reza Mafi Farabi Hospital, Tehran University of Medical Sciences, Tehran, Iran 2021 09 23 2022 01 06 Femoroacetabular impingement (FAI) could cause early osteoarthritis in patients. It is important to diagnosis this condition in the early stages to avoid osteoarthritis. The radiological x-ray is one of the main methods to diagnose FAI. There are many radiological signs which help orthopedic surgeons to diagnose FAI in the pelvic x-ray. Recent studies revealed many new signs for diagnosis and in the present concept article, we try to review all the radiological signs of the FAI in the pelvic and hip x-ray. https://jost.tums.ac.ir/index.php/jost/article/view/315 https://jost.tums.ac.ir/index.php/jost/article/download/315/251