Table 1 Inclusion and exclusion criteria

Patients undergoing hip arthroscopy for FAI between 1/2009 and 8/2012

Indication for arthroscopic surgery: groin pain, at least on positive clinical test (FABER, FADIR, anterior impingement test, apprehension test), radiographic signs of FAI (alpha angle > 55° or center of femoral head medial to posterior wall or posterior acetabular wall crosses anterior acetabular wall), labral tear in MRI

Other indication for hip arthroscopy (trauma, ECF, empyema)

Age at time point of surgery between 40 and 65 yrs

Preoperative radiological diagnostic (plain radiograph in anterior posterior or cross table projection)

No preoperative plain radiograph.

At least 12 mos post hip arthroscopy