Femoroacetabular Impingement (FAI)

A sports injury that occurs in the hip

Anatomy of the area offected

    • The hip is a ball and socket joint. The socket is referred to as the acetabulum, which is part of the large pelvis bone. The ball is the femoral head, which is the upper end of the femur.

    • A slippery tissue called articular cartilage covers the surface of the ball and the socket. It creates a smooth, low friction surface that helps the bones glide easily across each other.

    • The acetabulum is ringed by strong fibrocartilage called the labrum. The labrum forms a gasket around the socket which adds stability.

What is it?

  • FAI is a condition which unnatural bone growth on the neck of the Femur or the Acetabulum (socket which the Femur rests) causes the bones to rub up against each other during movement causing strenuous pain for the athlete.

  • There are two different forms of FAI

  • Pincer: which is where the unnatural bone growth occurs on the acetabulum/socket of the pelvis

  • Cam: which is where the unnatural bone growth occurs on the neck of the Femor

How it starts

  • Only about 10-20% of people have a chance of developing this issue in the first place but for those 10-20% the growth comes from excessive movement of this joint (usually in sports). The excessive movement irritates the bone and causes the the Osteoblasts to build up more bone on that area to protect it.The sports that are known to bring forth FAI are Golf, Football, Baseball, Volleyball, Soccer, Hockey, Lacrosse, Field Hockey, Martial Arts, Rowing, and Tennis. Although these few sports are known to bring about FAI among those who are at risk that does not mean that other sports wont bring about FAI because FAI comes from a forceful rotation in the core, including the hips. So really you could get FAI from any sport if you’re working hard enough in it and are part of that 10-20% that are susceptible to getting it.


  • 10-20% of people in the general population are vulnerable to FAI

  • 93% of professional athletes returned to their sports following corrective orthopaedic surgery for FAI, according to a study of 45 men and women.

  • 78% of pro athletes remained active for a year and a half after the orthopaedic surgery(same study)

    • we can conclude that arthroscopic surgery fixes the problem in the short run but in the long run the bone deformations will rebuild themselves if they continue to engage in physical activity.


  • The surgery undergone by athletes is called orthopaedic and has been proven to be initially successful. However, statistics show that even though orthopaedic surgery does correct the issue, it does not prevent it from occurring again so it still keeps athletes from participating in their favorite sports.

  • Fun fact, Greg Norman, Mario Lemieux, Kurt Warner, and Alex Rodriguez.


"Femoroacetabular Impingement (FAI)-OrthoInfo - AAOS."Femoroacetabular Impingement (FAI)-OrthoInfo - AAOS. Web. 15 Dec. 2015.

"Hip Injuries and Disorders: MedlinePlus." U.S National Library of Medicine. U.S. National Library of Medicine. Web. 15 Dec. 2015.

"Everything You Need to Know About Hip Injuries." Core Performance Core Daily. Web. 15 Dec. 2015.