Femoral-Acetabular Impingement (FAI)

Femoral-acetabular impingement is a hip problem that can occur in patients of all ages. The hip is a ball-and-socket joint which connects the femur and the pelvic bone. The acetabulum is the “socket” part of the joint, which holds the femoral bone in place. These bones move together in a normal, healthy way with smooth and cushioned movement. Sometimes, due to varying factors, the bones are misshapen or swollen and begin to rub against one another. This is known as impingement. If this occurs, hip movement can become limited and very painful. 

Causes of Hip Impingement

The underlying cause of all hip impingement is bone deformity. Either of the two parts of the ball-and-socket joint can be malformed. The formation of these bones may have been misshapen through genetics, injury, or age. Some patients can be born with or develop hip impingement at an early age, but not experience pain until later in life. Common injuries that can cause hip impingement are sports injuries, car accidents, or falling and breaking the hip. Age can lead to arthritis as the cartilage and tissue degenerate around the bones, causing them to rub together and begin to warp. No matter the underlying cause, femoral-acetabular  impingement is very serious, as the bones are deformed in such a way that the hip joint eventually cannot function correctly. 

Symptoms of FAI 

The main symptom of hip impingement is a feeling of stiffness. This stiffness can present itself in the hip, groin, or thigh. Some patients may mistake this stiffness for other problems at first. This can lead to the joint clicking or locking in place. Most people also experience pain on some level. This can start out generally with pain only when moving the hip into a certain position or after a lot of physical exertion. In more severe cases, the patient usually experiences a loss of motion and difficulties with walking or sitting for long periods of time. Usually with a loss of motion, most people experience more pain as well. 

How is Femoral-Acetabular Impingement Diagnosed?

Most doctors diagnose FAI with a variety of tests. Usually this testing begins with a simple physical examination that includes the patient moving their leg and hip in different ways. The doctor will evaluate the range of motion and areas which are most painful. Generally, the next step will be an x-ray to determine the state of the bones. Many doctors will also order an MRI to get a clear picture of the exact conditions of the surrounding tissue in the hip as well. They may also order a CT scan to get any additional information about the hip and the surrounding area. 

Hip Impingement Treatments

Because the symptoms of FAI vary, the treatments are very different based on the severity of the symptoms. In less serious cases, rest and activity modification can be effective for quite some time. Physical therapy is highly recommended to help strengthen the joint and muscles around it to prevent pain. For most mild and moderate cases, physical therapy will be the first course of action that the doctor prescribes. Some injections and other medication-based treatments are available for pain reduction and joint health. For patients with severe symptoms or extreme bone deformity, the best course of action is often surgical intervention. Several different surgical options are available, including filing down the deformed bones (called resurfacing), removing portions of the bone, or complete hip replacement. 

Is Professional Treatment Needed for FAI?

Hip impingement will not go away on its own and is definitely an ailment that needs professional treatments. Patients who are experiencing this kind of pain need to be treated as quickly as possible to avoid more serious symptoms and long-lasting effects. Although femoral-acetabular impingement can be very serious, it is treatable and for the most part, curable.