In a patient with suspected femoroacetabular impingement, which hip exam test is commonly used?

• A. FABER test
• B. Ober test
• C. Log-roll test
• D. Flexion, Adduction, Internal Rotation (FADIR)

Answer: (D)

Testing for femoroacetabular impingement hinges on reproducing the impingement stress by placing the hip in the position that most commonly causes contact between the femoral head/neck and the acetabular rim. In FAI, abnormal geometry from either CAM or pincer lesions leads to impingement during flexion with adduction and internal rotation, so a provocative pain response in that position points to this condition.

The FADIR maneuver does just that: with the patient supine, the hip is flexed about 90 degrees, adducted across the midline, and internally rotated. If this position reproduces groin pain or reveals an internal snapping or reduced range, it suggests anterior-superior impingement consistent with FAI.

This is why it’s commonly used—because it directly tests the most likely impinging posture for FAI. Other tests have different purposes: FABER is a broader hip-provocation test that isn’t as specific for anterior impingement; Ober targets iliotibial band tightness; the log-roll assesses intra-articular or laxity issues but not the classic impingement position. So, FADIR uniquely targets the key position that reveals FAI during the exam, guiding further imaging and management.