Everything you need to know about femoroacetabular impingement (FAI)

Femoroacetabular impingement (FAI) is a condition that can profoundly affect hip function and overall quality of life. Mr Giles Stafford, renowned consultant orthopaedic hip surgeon, provides an expert insight.

What is femoroacetabular impingement (FAI)?

Femoroacetabular impingement (FAI) is a hip condition that occurs when there is an abnormal contact between the femoral head (the ball of the hip joint) and the acetabulum (the socket of the hip joint). This abnormal interaction can cause hip pain as well as damage to the cartilage and labrum (a ring of cartilage that cushions the hip joint).

The main signs and symptoms of FAI thus include:

• hip pain, usually felt in the groin area
• stiffness and reduced range of motion in the hip joint
• clicking or locking feelings in the hip joint
• pain with activities that involve hip flexion, such as sitting or running

What are the causes of femoroacetabular impingement (FAI)?

FAI is primarily caused by structural abnormalities in the hip joint. The two most common types of impingement are:

• Cam impingement: This type occurs when the femoral head has an abnormal bump or deformity that prevents smooth movement within the acetabulum. This bump can cause friction between the femur and acetabulum, leading to damage over time.
• Pincer impingement: This type is characterised by an overgrowth of the acetabulum, which covers too much of the femoral head. The excessive coverage can lead to abnormal contact and compression during hip movement.

In some cases, FAI can result from a combination of both cam and pincer impingements. Other factors that can contribute to the development of FAI include genetics, repetitive hip movements, and previous hip injuries or fractures.

How is femoroacetabular impingement (FAI) diagnosed?

Diagnosing FAI involves a thorough process to ensure accurate identification and assessment of the condition.

The first step involves reviewing your medical history, which includes examining any previous hip injuries, symptoms, and activities that may contribute to the condition. Following this, a physical examination is performed to assess your hip’s range of motion, check for pain or discomfort during specific movements, and identify any abnormal physical signs.

To confirm the diagnosis and evaluate the extent of the condition, imaging studies are then typically conducted. X-rays are commonly used to provide a visual of the bone structure, revealing any abnormal bone formations or joint irregularities, while MRI scans offer detailed images of soft tissues that help in identifying any damage or abnormalities not visible on X-rays.

What is the treatment for femoroacetabular impingement (FAI)?

Treatment options for FAI include both conservative management and surgical intervention.

Conservative management involves:

• Physical therapy to strengthen the muscles around the hip joint, improve flexibility, and correct movement patterns contributing to symptoms.
• Medications, such as non-steroidal anti-inflammatory drugs (NSAIDs) or other pain relievers, can help reduce inflammation and manage pain.
• Activity modification, such as adjusting or avoiding activities that exacerbate symptoms, can provide relief and prevent the condition from worsening.

If conservative measures are insufficient, surgical intervention may then be necessary.

Surgical intervention may involve either:

• Arthroscopy, a minimally invasive surgery, involves making small incisions to insert a camera and instruments into the hip joint. Your orthopaedic surgeon then removes or reshapes the abnormal bone structures, repairs damaged cartilage, and addresses other issues within the joint.
• Hip resurfacing or hip replacement: In severe cases where there is significant damage or arthritis, more extensive surgical procedures like hip resurfacing or total hip replacement may be considered.

Can femoroacetabular impingement (FAI) lead to arthritis?

Yes, if left untreated or if not managed appropriately, FAI can lead to joint damage and increase the risk of developing osteoarthritis. The constant abnormal contact between the femur and acetabulum can result in cartilage wear and tear, which may eventually lead to the development of arthritis. Early diagnosis and effective management of FAI are thus crucial in preventing long-term joint damage and preserving hip function.

If you would like to book an appointment with Mr Giles Stafford, head on over to his Top Doctors profile today.