Femoroacetabular impingement (FAI), also called hip impingement, is a condition where the hip joint is not shaped normally. This causes the bones to painfully rub together. This condition can be treated with corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs), physical therapy, rest and surgery.
FAI is an unusually shaped hip joint that causes two bones in the hip to rub together. The pressure causes friction between the top of the femur (thighbone) and acetabulum (part of the pelvis). FAI can limit motion and cause pain.
Without treatment, FAI can damage the cartilage that provides cushioning in the hip. This damage can lead to arthritis, or painful joint deterioration. Some people need surgery to repair the damage. FAI is also called hip impingement.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
FAI is a common cause of hip pain in adolescents, adults and athletes of all ages.
The hip joint is a ball-and-socket joint that attaches the femur to the pelvis. People with FAI have an abnormality in the ball (top of the femur) or the socket (groove in the hip bone). The abnormality causes friction during movement and can damage the surrounding cartilage and labrum (cartilage that lines the hip socket).
The abnormalities associated with FAI are usually present at birth. But they can develop later in life, especially during the teenage years. Doctors classify FAI into one of three categories based on the cause:
Physically active people may experience pain from FAI earlier than people who are not as active. But in most cases, exercise does not cause FAI.
Some people with FAI notice no symptoms. Signs of the condition may appear as damage in the hip worsens. The signs and symptoms of FAI include:
Doctors use several tests to diagnose FAI. Your doctor will ask about your family history and activity levels. To confirm a diagnosis of FAI, your doctor may use:
FAI treatment varies according to the person and the severity of the damage. Treatment options for FAI include:
Some people with FAI who do not receive treatment develop hip osteoarthritis (breakdown of the cartilage around the hip). This complication can lead to severe pain and limited mobility.
Most cases of FAI cannot be prevented. Prompt treatment is important to prevent FAI from causing more damage in the hip.
In some cases, people who are physically active have a higher risk of developing FAI.
Doctors can successfully treat many cases of FAI. Many people who receive treatment for FAI go on to live long and active lives without hip pain.
Contact your healthcare provider if you or your child experiences symptoms of FAI.
If you have FAI, you may want to ask your doctor:
Last reviewed by a Cleveland Clinic medical professional on 07/02/2019.
Learn more about our editorial process.