What is femoroacetabular impingement syndrome?

Femoroacetabular impingement (FAI) syndrome is a condition involving an irregular shape of the hip bones. The irregularity is caused by extra bone growth in one or both of the bones that form the hip joint. As the bones cannot fit together correctly, they rub against each other during movement, causing pain and limited mobility.

What are the symptoms?

The most common symptoms of femoroacetabular impingement syndrome are pain, stiffness, and limping. Most people with this condition experience pain in the groin area, and pain may also occur toward the outside of the hip. In some cases, pain occurs in the form of a dull ache, but it may be sharp and stabbing with turning, twisting, or squatting.

What is the cause of FAI?

This condition occurs when the hip bones do not form normally during growth. It is a deformity that leads to joint damage and pain. When symptoms develop, it typically indicates that damage has occurred to the articular cartilage or labrum, and the disease is likely to progress. Athletes may experience pain earlier, as they may work the hip joint more vigorously; however, exercise does not cause femoroacetabular impingement syndrome.

What is the anatomy of femoroacetabular impingement syndrome?

With FAI syndrome, the bones of the hip joint come too close, causing friction and pinching tissue. Normally, the ball of the hip joint (femoral head) sits on the femoral neck somewhat like ice cream sits on a cone. Pinching, friction, and damage to the hip joint occur with femoroacetabular impingement when the femoral head and neck contact the socket (acetabulum). Pinching and friction can damage the fibrous cartilage lining the outer edge of the socket (labrum) and/or the articular cartilage that protects the bones and allows them to glide smoothly together.

Woman stretching her hip on a bench outside
Steve Yoon MD

Schedule a Consultation

Contact Us

What are the treatment options?

If you suffer with femoroacetabular impingement syndrome, Dr. Yoon can tailor a treatment plan for you. He offers the most advanced regenerative treatments and may recommend any or a combination of the following or other treatments:

Corticosteroid injections: These anti-inflammatory medications may provide relief from FAI symptoms when injected directly into the hip joint. Corticosteroids relieve pain and swelling by reducing inflammation.

Platelet rich plasma injections: Platelet rich plasma (PRP) is taken from your own blood. It is plasma with a higher than normal concentration of platelets, cells responsible for clotting that contain growth factors to stimulate healing and relieve pain. PRP injections are performed with ultrasound guidance to ensure precision.

Stem cell injections: Stem cells are special cells found in the human body that have the capability of developing into many different types of cells, and in some cases, to repair damaged tissue. When injected into an impinged hip joint, stem cells can help promote regrowth and healing of the damaged cartilage.

Message Us