Sports Medicine: Femoral Acetabular Impingement (FAI)

What is femoral acetabular impingement?

Femoral acetabular impingement or “FAI” affects the hip and most often occurs in sports that involve repetitive hip motion, such as soccer. This injury is characterized by an abnormal contact between the head/neck junction of the femur and the acetabulum or “hip socket”.

What causes femoral acetabular impingement?

Femoral acetabular impingement results from an abnormality of the femur (cam impingement), the acetabulum (pincer) or most often a combination of both. A cam impingement involves the head and neck of the femur. In a cam impingement, the head of the femur is not completely round which causes it to have increased contact with the acetabulum during hip motion. In a pincer impingement, the socket covers too much of the head of the femur, creating too much contact with the head/neck junction. If either or both of these conditions are present, a pinching of the cartilage occurs and can lead to early arthritis.

What are the symptoms of femoral acetabular impingement?

Athletes suffering from femoral acetabular impingement may suffer from a gradual onset of groin, low back and general hip pain that becomes more debilitating over time. Athletes may also feel a popping or catching in the hip that is not always painful.

How is femoral acetabular impingement diagnosed?

A thorough history and physical examination by a physician will often recreate symptoms or reveal a limit in the athlete’s range of motion in the injured hip. If the physician suspects FAI, x-rays and an MRI may be ordered to determine the severity of the damage to the hip cartilage.

What is the treatment for femoral acetabular impingement?

Depending on the symptoms, treatment options vary. If the symptoms are minor, the athlete may be shown how to adjust their activity and manage the discomfort after activity. Most often in young athletes, however, surgery is the preferred management. Surgery to shave down the extra bone will allow more normal hip movement and decrease the damage to the cartilage.

What is the long term outlook for femoral acetabular impingement?

With early treatment and proper rehabilitation, athletes with femoral acetabular impingement should expect a full return to activity.