What Is Femoroacetabular Impingement?
Femoroacetabular impingement (or FAI) is a musculoskeletal condition of the hip. It involves extra bone growth (a bone spur) around the ball at the top of the femur and/or the hip socket—the femoroacetabular structure. When this happens, the ball and socket don’t fit together properly and the bones rub against each other when the person moves. The “impingement” refers to the extra contact between the ball and socket when an individual with FAI holds the hip in certain positions.
There are three types of femoroacetabular impingement: cam bone spur, pincer bone spur, or both. The resulting friction from this bone deformity can lead to joint damage, so early diagnosis and treatment is important.
Who Is Most At Risk Of Developing Femoroacetabular Impingement?
Femoroacetabular impingement is a bone deformity present at birth—there is no activity that puts any one group at risk of developing femoroacetabular impingement. However, in terms of the hip pain associated with FAI, it is most common among active adolescents and young adults. Males are affected by this hip pain or groin pain more often than females.
Because of their high activity level, young athletes may start experiencing the pain associated with FAI earlier than less active adults. Sports in which this pain usually occurs include basketball, soccer, and dance. However, FAI is not caused by exercise (it is a condition that already exists); rather, the risk of developing pain associated with femoroacetabular impingement is often a result of exercise.
How Is Femoroacetabular Impingement Diagnosed?
Our pediatric orthopedists will seek a femoroacetabular impingement diagnosis based on your child’s history and a physical examination. During this physical exam, we will conduct an impingement test, in which the orthopedist brings the child’s knee toward the chest and rotates the knee toward the opposite shoulder. If your child expresses hip pain during the test, we generally consider it a positive diagnosis for impingement.
In addition, our orthopedists will confirm FAI with an X-ray or a CT scan to evaluate the shape and condition of the hip’s ball and socket or do an MRI to evaluate the hip joint’s soft tissue. A local injection of numbing medicine in the hip joint also helps us confirm a femoroacetabular impingement diagnosis if the medicine provides temporary pain relief.
Symptoms Of Femoroacetabular Impingement
Femoroacetabular impingement symptoms are often mild at the start—such as a dull ache—and may not progress for many years. The most common symptoms of femoroacetabular impingement are pain in the hip or groin, stiffness in the hip, and limping. The pain may also be felt in the lower back, buttocks, thigh, or knee. Your child may also complain of a popping or clicking sensation in the hip.
Although the pain symptoms may be mild at first, they (and other symptoms) can get worse quite rapidly in many cases. The debilitating pain from FAI may cause your child to stop participating in sports or physical activities that exacerbate the pain.
Worsening pain is often felt when the person sits for long periods of time, including sitting with hips flexed at a 90-degree angle; when squatting, twisting, or turning; or during periods of intense athletic or other physical activity. If not diagnosed and treated, repeated impingement can damage the hip joint and/or lead to osteoarthritis in the hip.
What Are The Causes Of Femoroacetabular Impingement?
There are several courses of treatment to fix femoroacetabular impingement, both non-invasive and surgical.
Nonsurgical options include specific femoroacetabular impingement exercises with a physical therapist. These exercises focus on increasing the range of motion, improving balance, and building hip strength. They include stretching exercises that work on different muscle groups around the hip and buttocks. Other femoroacetabular impingement exercises are for core strengthening, balance, and functional training for the hips, pelvis, and lower extremities. For student-athletes, those may be learning to jump and land properly and safely or hop testing and training.
Our pediatric orthopedists may also recommend rest and modifying physical activity to reduce pain and anti-inflammatory medications to alleviate symptoms.
Femoroacetabular impingement surgery is needed for patients that don’t respond to non-surgical treatment. There are two FAI surgeries: arthroscopic hip surgery in which the surgeon trims the excess bone and cleans out any existing damage to the area, and a periacetabular osteotomy, in which we cut and rotate the bone around the socket. These procedures are done to eliminate the FAI and help prevent further damage to the hip joint. In some cases, we may perform a combination of both femoroacetabular impingement surgeries.
Consult With TPOC About Your Child’s Femoroacetabular Impingement
If your young child or teenager is complaining of hip or groin pain, it’s time to make an appointment at TPOC with one of our pediatric orthopedists. We will do a thorough examination and evaluate your child’s condition. If we diagnose femoroacetabular impingement, we’ll recommend the appropriate course of treatment. You can make an appointment at one of our four northern NJ pediatric orthopedic offices.