Hip
Femoroacetabular Impingement (FAI)
What is FAI?
FAI (femoroacetabular impingement) is a common hip joint disorder in young, active patients caused by a structural problem, specifically abnormal bone growth, that leads to irregular contact between the acetabulum and the femoral head. The hip is a ball and socket joint. The socket is the part of the hip bone called the acetabulum, and the head of the femur is the ball. Articular cartilage covers both the ball and the socket and functions to reduce friction for smooth joint movement. In a healthy hip, the ball of the femur fits perfectly into the acetabulum. However, in individuals with FAI, there may be irregularities in the shape of either the ball or the socket, or both. These irregularities cause hip joint impingement during activities like walking, running, or bending the hip, which can result in hip impingement symptoms such as groin pain and discomfort.
The location of the hip impingement can be described as either CAM impingement or Pincer impingement, or both. The CAM type is caused by the abnormal shape of the femoral head and neck, while the Pincer-type is caused an abnormal shape of the acetabulum. In some cases, both types can co-exist.
The friction and pressure caused by FAI can lead to further hip joint damage over time, including bone spurs, a labral tear, and hip osteoarthritis. Thus, early hip impingement diagnosis by a hip impingement specialist is crucial.
What is a labral tear?
The hip labrum is a ring of cartilage that surrounds the hip socket, providing stability to the joint. The hip labrum plays an important role in maintaining normal hip function. It functions to tighten the seal between the bones for joint stability, allows for a wide range of motion and helps to maintain the alignment between the bones. A hip labral tear occurs when this cartilage is damaged or torn, often due to a hip injury, degeneration, or FAI. This tear can lead to a range of symptoms, including hip labrum pain (groin pain), clicking or catching sensations, and a decreased range of motion.
What causes FAI?
The bone abnormality of FAI may be a developmental deformity or acquired, meaning caused by injury or repetitive movements. Hip deformities and the abnormal growth of bone on the ball and/or the socket alter normal biomechanics and lead tohip labrum injury, and accelerated joint degeneration. FAI may not cause problems until the hip is overused through activities that involve repetitive hip motions or pushed beyond the hip’s normal range of motion.
What are the symptoms of FAI and a hip labral tear?
- Intermittent deep groin pain or ache (most common)
- Pain at the outside of the hip joint
- Sharp stabbing pain when twisting, turning or squatting, such as when getting in or out of a car or a chair
- A dull ache from prolonged sitting or walking
- A sensation of catching, clicking, or locking in the hip joint during movement
- Instability of the hip joint
- Stiffness and reduced flexibility in the hip joint
- Limping
How is FAI diagnosed?
During your consultation with Dr. Bryan Penalosa, a Chicago sports medicine surgeon and FAI specialist, your medical history, FAI symptoms, and past injuries will be reviewed.
Physical Exam
Dr. Penalosa will conduct a physical examination checking range of motion including flexion, adduction, and rotation to diagnose your hip impingement. The hip impingement test will also be performed during your physical exam. This is a test in which Dr. Penalosa will ask you to bring your knee to your chest while he rotates the knee in toward the opposite shoulder (FADIR: flexion, adduction, and internal rotation). If the hip impingement test causes pain, you likely have a hip labral tear. A comprehensive physical exam is key to determine the cause of your hip pain.
Imaging
Diagnostic imaging is necessary to definitively diagnose FAI and a hip labral tear. X-rays will reveal abnormally shaped bones, and an MRI will reveal damage to the soft tissue, such as the labrum (a hip labral tear). A CT scan is usually not necessary, but in some cases Dr. Penalosa may order one, as it can provide details about the shape of the bones, location of abnormal bone growth, and the rotation of the bones.
Hip Injection
An intra-articular hip injection can help to confirm the diagnosis of hip impingement. This injection will be performed in the office at the time of your visit under ultrasound guidance. If the majority of your pain goes away, even temporarily, following the injection, then it confirms that the source of the pain is due to FAI.
Femoroacetabular Impingement (FAI) Treatment Options
Can FAI be treated without surgery?
Some people live active lives, never knowing they have FAI, and don’t have any hip pain. By the time symptoms develop, there is usually some damage to the hip labrum, and with repeated use, the damage may progress. The reason athletes are often diagnosed with FAI is because they overuse the joint in extreme ranges of motion, which damages the labrum and causes hip pain. In mild to moderate cases, FAI pain can be treated without surgery.
Non-operative treatment of FAI involves a change in activities to avoid movements that cause hip pain, including taking time off from activities that cause hip pain, using over-the-counter anti-inflammatory medications to reduce pain and inflammation, and physical therapy. Typically, symptoms will resolve within several weeks of conservative, non-surgical treatment. A steroid injection can also help relieve hip pain. If your hip pain is resolved with non-operative treatment and you are able to return to your desired level of activity, then no FAI surgery is needed.
What are the surgical options for FAI?
When nonsurgical FAI treatments do not relieve hip pain and imaging confirms FAI with an associated hip labral tear, hip surgery is a reasonable option. FAI surgery can be performed in a minimally invasive procedure called hip arthroscopy. FAI surgery is usually an outpatient procedure, and you will go home the same day. During your FAI surgery, Dr. Bryan Penalosa will remove the abnormal bone growth causing the hip impingement and repair the labral tear. On rare occasions, more commonly associated with revision hip surgery, a labral reconstruction may be indicated. Surgery typically lasts about 1-2 hours. Hip surgery is customized for each patient based off of each patient’s unique hip anatomy and hip condition.
Recovering from Femoroacetabular Impingement (FAI) Surgery
How long is the recovery after FAI surgery and labral repair?
The recovery time after FAI surgery with labral repair can vary depending on several factors, including the extent of the surgery, individual patient characteristics, and the level of activity that the patient is striving to return to. In general, most patients can recover full, unrestricted activity in 4-6 months following FAI surgery so long as they complete a good physical therapy program.
Here’s a general overview of what to expect after FAI surgery:
Initial Recovery Phase (0-6 weeks):
The immediate post-operative period following FAI surgery involves rest and protection of the surgical site. Patients will be non-weight bearing for 2 weeks following hip surgery, typically using crutches for a total of 2-4 weeks. A hip brace will be worn for 2 weeks following surgery. Physical therapy and the use of a continuous passive motion machine will begin on post-operative day 1 to improve range of motion and reduce swelling. Pain and discomfort are common during this phase, but medications are prescribed to help manage it.
Intermediate Recovery Phase (6-12 weeks):
During this time, physical therapy intensifies to improve strength, stability, and mobility. Return to light, low-impact activities may be allowed under the guidance of Dr. Bryan Penalosa and his team, as well as your physical therapist. Patients should still avoid high-impact activities or activities that involve excessive hip stress.
Advanced Recovery Phase (3-6 months):
As strength and range of motion improve, patients can start transitioning to more demanding activities. Physical therapy continues to focus on functional movement and sport-specific exercises. Return to full activities, including sports, typically occurs around 6 months following FAI surgery after Dr. Bryan Penalosa has formally evaluated and cleared the patient to do so.
Long-Term Recovery (6 months to 1 year and beyond):
Complete recovery may take up to a year or more. Patients should continue with maintenance exercises to ensure long-term joint health.
Long-Term Effects of Untreated FAI
What are the long-term effects of untreated FAI? Can FAI lead to hip arthritis?
Hip preservation refers to the use of procedures to protect and maintain the labrum (the cartilage that lines the hip bone to deepen the hip socket) to prolong the natural lifespan of the hip, prevent arthritis of the joint, and to avoid or delay hip replacement surgery. FAI predisposes to premature joint degeneration.
Untreated FAI can indeed lead to long-term complications, and one of the potential consequences is the development of hip arthritis. Here are some of the long-term effects of untreated FAI:
Progressive Hip Joint Damage
FAI involves abnormal bone growth in the hip joint, causing friction and hip impingement during movement. Over time, this repetitive mechanical stress can lead to the gradual wear and tear of the hip joint tissues, including the cartilage lining the joint.
Cartilage Damage
As FAI persists, the friction within the hip joint can damage the articular cartilage, which provides a smooth surface for joint movement. This cartilage damage can result in hip pain, joint stiffness, and decreased mobility.
Hip Arthritis
Perhaps one of the most concerning long-term effects of untreated FAI is the development of hip osteoarthritis. The gradual wear and tear on the joint’s cartilage and other structures can eventually lead to arthritis, characterized by pain, inflammation, joint deformity, and reduced mobility.
Labral Degeneration
FAI can cause the labrum, a ring of cartilage that lines the hip socket, to deteriorate over time. A damaged labrum can contribute to hip pain and instability.
Secondary Hip Conditions
Untreated FAI can increase the risk of developing secondary hip conditions, such as tendinitis, hip bursitis, and muscle strains, due to altered hip mechanics and abnormal loading of the joint.
It’s important to note that not everyone with FAI will progress to hip arthritis or develop long-term effects of FAI, and the rate of progression can vary widely among individuals. However, addressing FAI early through conservative treatments or surgical intervention can help reduce the risk of these long-term complications and improve hip joint function and overall quality of life.