Femoroacetabular Impingement

There are two forms of femoroacetabular impingement. Most cases involve a combination of the two.

• Cam Impingement - occurs when the femoral head and neck are misshapen, often due to extra bone formation. The irregular shape causes abnormal contact between the joint surfaces.

• Pincer Impingement - occurs when the acetabulum (hip socket) has excessive coverage over the femoral head. This overgrowth can pinch the labrum, leading to pain and damage. In some cases, a hip socket that is abnormally angled backward may also contribute to impingement.

FAI can cause a variety of symptoms, including:

• Groin pain during hip movement
• Pain in the front, side, or back of the hip
• Pain that ranges from a dull ache to sharp sensations
• A locking, clicking, or catching feeling in the hip
• Increased pain in the inner hip or groin after prolonged sitting or walking
• Difficulty walking uphill
• Restricted hip mobility
• Low back pain
• Pain in the buttocks or outer thigh

Athletes such as football players, weight lifters, and hockey players and people who perform manual labour are more at risk of FAI.

Other risk factors include people with:

• Repetitive hip flexion
• Congenital hip dislocation
• Anatomical abnormalities of the femoral head or angle of the hip
• Legg-Calves-Perthes disease: a form of arthritis in children where blood supply to bone is impaired causing bone breakdown.
• Trauma to the hip
• Inflammatory arthritis

While non-surgical treatments do not correct the underlying structural abnormalities, they can help alleviate pain and improve mobility.

To treat the underlying strucutral issues, a hip arthroscopy is usually needed to repair the damage and reduce the risk of developing early osteoarthritis.