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Femoroacetabular Impingement

Also known as: FAI, hip impingement, CAM lesion of hip, pincer lesion of hip

What is femoroacetabular impingement?

Femoroacetabular impingement (FAI) occurs from excessive contact between the proximal femur (hip) and acetabulum (hip socket).

What causes femoroacetabular impingement?

This can be caused by an abnormality of the proximal femur, acetabulum or both.

What are the symptoms of FAI?

Common symptoms of femoroacetabular impingement include pain in the groin or thigh with sitting, walking or running.

What are femoroacetabular impingement care options?

Modification of activities and physical therapy can help decrease the pain associated with femoroacetabular impingement. If these treatments are not successful, open or arthroscopic surgery may be performed to normalize the anatomy of the hip joint.

Reviewed by: Kevin S Horowitz, MD

This page was last updated on: September 16, 2025 12:32 PM

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