The Flexion, Adduction, and Internal Rotation (FADIR) test is a highly sensitive physical examination technique used by clinicians to screen for issues within the hip joint. This non-invasive, in-office procedure serves as a primary tool to quickly assess patients presenting with hip or groin pain. It helps determine if the source of the discomfort originates from structures inside the hip joint itself, distinguishing intra-articular problems from other potential causes. The test is a preliminary screening measure, indicating a high suspicion of certain hip pathologies that require further diagnostic imaging.
The Procedure and Rationale of FADIR
The FADIR test is performed with the patient lying on their back, allowing the examiner to passively move the leg being tested. The procedure begins by bringing the hip into Flexion, typically to 90 degrees, positioning the thigh perpendicular to the body. From this flexed position, the examiner introduces Adduction, moving the knee across the midline toward the opposite leg. This movement brings the neck of the femur closer to the rim of the acetabulum.
The final and most provocative step is Internal Rotation, where the examiner rotates the ankle outward while simultaneously pushing the knee inward. This triple combination of movements—Flexion, Adduction, and Internal Rotation—is specifically engineered to be a capsular closing and impingement maneuver. The biomechanical rationale is that this position intentionally jams the femoral head and neck against the anterior-superior rim of the acetabulum.
This intentional “jamming” action simulates the mechanical conflict that causes pain in a variety of hip conditions. If the structures at the front of the hip joint are damaged or abnormally shaped, this maneuver will compress or pinch them, reproducing the patient’s familiar pain. The combination of movements stresses the joint capsule, compresses the labrum, and forces any bony abnormalities into contact.
Primary Conditions Identified by FADIR
The FADIR test is primarily designed to screen for Femoroacetabular Impingement (FAI) and acetabular labral tears, which are often interrelated conditions. FAI involves extra bone growth developing on one or both main bones of the hip joint, causing them to rub against each other during movement. This abnormal contact causes characteristic hip pain, particularly in positions of deep flexion.
The bony overgrowth in FAI presents in two main forms: Cam and Pincer impingement. Cam impingement involves a non-spherical shape of the femoral head and neck, causing it to jam into the socket. Pincer impingement involves excessive coverage of the femoral head by the acetabulum, creating an overhanging rim that pinches soft tissue.
A labral tear, a tear in the ring of cartilage that lines the rim of the hip socket, is another major pathology the test can identify. The labrum provides stability and seals the joint. The high-pressure compression generated by the FADIR maneuver can stress or pinch a torn labrum, causing pain or a catching sensation. Since FAI often leads to labral tears due to repeated mechanical trauma, a positive FADIR test frequently suggests the presence of both conditions.
Interpreting Positive and Negative Results
A positive FADIR test occurs when the maneuver reproduces the patient’s chief complaint of pain, typically described as a sharp, pinching sensation in the anterior groin or anterolateral hip. The reproduction of this familiar pain, or the presence of a palpable clunk or clicking sensation, raises a high suspicion of intra-articular hip pathology, such as FAI or a labral tear.
However, a positive FADIR test is a screening tool, not a definitive diagnosis, as the test has high sensitivity but generally lower specificity. High sensitivity means the test is effective at ruling out the conditions it screens for; if the result is negative, it is highly unlikely the patient has FAI. Conversely, low specificity means the test can sometimes be positive even when FAI or a labral tear is not the cause, suggesting other soft tissue or joint issues may be responsible.
A positive FADIR test necessitates further diagnostic confirmation, which often includes imaging studies. Clinicians typically order X-rays to assess bony morphology, specifically looking for Cam or Pincer abnormalities. They may follow up with a Magnetic Resonance Imaging (MRI) or Magnetic Resonance Arthrography (MRA) to visualize soft tissues, such as the labrum and cartilage. A negative FADIR test, where no pain is reproduced, helps rule out these hip pathologies.