Hip impingement (Femoroacetabular impingement or FAI) occurs when the bones of the hip joint do not fit together properly, leading to painful friction. This condition involves abnormal contact between the ball (femoral head) and socket (acetabulum) of the hip. Due to its underlying structural nature, hip impingement generally does not resolve on its own. However, it is often manageable with appropriate medical care and interventions.
Understanding Hip Impingement
Hip impingement is a mechanical disorder where extra bone growth or an irregular shape on either the femoral head or the acetabulum causes the bones to rub against each other during movement. There are typically two main types of FAI, and a combination of both.
Cam impingement occurs when excess bone on the femoral head makes it less round, preventing smooth rotation within the hip socket. Pincer impingement happens when the acetabulum (hip socket) has too much bony growth extending over its rim. Mixed impingement, the most common type, involves characteristics of both cam and pincer.
The development of these abnormal bone shapes often begins during childhood bone growth. Repetitive hip movements, particularly in sports that involve frequent hip flexion and rotation like football, soccer, or dance, can also contribute to or exacerbate symptoms. Common symptoms include pain in the groin area, which can be sharp or a dull ache, stiffness in the hip or thigh, a limited range of motion, and sometimes a clicking or popping sensation. Pain often worsens with activities like prolonged sitting, squatting, or turning and twisting the hip.
Why Spontaneous Resolution is Unlikely
Hip impingement is primarily a structural issue, meaning it involves physical abnormalities in the shape of the hip bones. These bony changes, such as extra bone growth on the femoral head or acetabular rim, do not naturally correct themselves over time. Therefore, the underlying mechanical problem that causes the hip bones to rub against each other will persist without intervention.
The repetitive abnormal contact between the femoral head and acetabulum can lead to damage of the soft tissues within the hip joint. This includes the labrum, a ring of cartilage that deepens the hip socket and provides stability, and the articular cartilage, which covers the bone surfaces for smooth movement. Labral tears, a common consequence of FAI, do not heal on their own because cartilage has a limited capacity for self-repair.
Even if symptoms temporarily improve with rest or activity modification, the structural issue remains. The continued friction can progressively wear down the cartilage and labrum, potentially leading to more extensive joint damage over time. This ongoing mechanical stress and resulting tissue damage explain why hip impingement typically does not resolve spontaneously and often requires management to prevent further complications.
Treatment Approaches
Managing hip impingement often begins with non-surgical approaches, especially for mild to moderate symptoms. Rest and activity modification are frequently recommended to avoid movements that aggravate pain. Over-the-counter anti-inflammatory medications, such as ibuprofen or naproxen, can help reduce pain and swelling.
Physical therapy plays a significant role in conservative management, focusing on strengthening the muscles around the hip and core, improving flexibility, and correcting movement patterns. Injections, such as corticosteroids, may be administered directly into the hip joint to temporarily reduce pain and inflammation.
If non-surgical methods do not provide sufficient relief or if there is significant structural damage, surgical intervention may be considered. Hip arthroscopy is a minimally invasive procedure commonly used for FAI. During arthroscopy, a surgeon uses small incisions and specialized instruments with a camera to reshape the bones (osteoplasty) and repair or reconstruct the torn labrum. The goal of surgical treatment is to address the underlying bony deformity and any associated soft tissue damage, aiming to reduce pain, restore function, and prevent further joint degeneration.
Prognosis and Long-Term Considerations
The long-term outlook for individuals with hip impingement can vary, but timely and appropriate treatment generally leads to improved outcomes. Effective management, whether through non-surgical or surgical means, can significantly reduce pain and enhance hip function. Adherence to rehabilitation programs, particularly after surgery, is important for regaining strength and mobility.
Treating hip impingement can also play a role in potentially reducing the risk of developing osteoarthritis in the future. While there is a belief that correcting the impingement may prevent or delay the onset of arthritis, long-term studies are ongoing to fully confirm this theory. Some individuals may experience recurrence of symptoms or require ongoing management, especially if the underlying structural issues are complex or if they return to high-impact activities.
Living with FAI involves understanding that while the condition may not spontaneously disappear, its symptoms can be effectively managed. Patients can often return to an active lifestyle, though some modifications to certain movements or activities might be necessary. Regular follow-up with healthcare providers helps monitor hip health and address any new concerns, ensuring the best possible long-term outcome.