All patients will undergo imaging (which may include CT scan or at least 1.5 Tesla magnetic resonance imaging MRI) prior to the surgical assessment as part of routine care. All patients will also undergo standardized radiographs of the hips and pelvis also as part of routine care. Plain radiographs will be examined for evidence of osteoarthritis as joint space narrowing, osteophytes, cysts and subchondral hypertrophy. Several radiographic measurements will be performed among them: the alpha angle and lateral center-edge angle will be determined for the presence of FAI. Radiographs will also be part of follow-ups.