FAI develops when the hipbones fail to form normally and have activity beyond the limit of what they can tolerate. The exact causes of abnormal hip joint development are not known.

FAI sometimes develops after someone has had Legg-Calve-Perthes (LCP) disease, slipped capital femoral epiphysis (SCFE), or other related pediatric diseases of the hip.

Although FAI is not directly caused by exercise, it can develop in growing children due to increased activity.

FAI and AHD (adolescent hip dysplasia) are often seen together in patients.

FAI may not be noticed early on if it is very mild and does not cause any symptoms.

FAI symptoms include:

• Trouble participating in sports or recreational activities due to hip pain or fatigue
• Increasing pain in the hip or groin
• Trouble sitting or riding in a car for long periods of time
• Interruption of normal everyday activities due to pain
• Poor endurance
• Hip joint catching or locking
• A limp or change in how the person walks
• A difference in the length of each leg

Symptoms can range from mild to severe and usually worsen over time.

Doctors will perform a physical exam to diagnose femoroacetabular impingement. To rule out other conditions and get a better view the hip anatomy, they may also use imaging. This may include one or more of the following:

• X-ray
• MRI 
• CT scan

The three types of FAI are:

• Pincer, where too much bone exists at the edge of the hip socket
• Cam, where too much bone is on the ball of the hip
• Combined, where both pincer and cam impingements are present

Treatment varies depending on the severity of FAI. The care team at Cincinnati Children’s, tailors treatment to each patient. Treatment can include:

• Adjusting levels of activity
• Physical therapy
• Anti-inflammatory medications
• Surgery (see different types described below)

Hip arthroscopy is a surgical treatment for the hip joint. The goal is to correct the abnormal bone growth on the hip joint. To do this, the surgeon makes small incisions at the hip. Through these incisions, the surgeon will reshape the bones and/or repair tears to the cartilage. More severe cases of FAI might need an open surgery that requires a larger incision.

Our surgeons have specialized training in both types of surgery used to treat FAI and perform these procedures routinely.

At Cincinnati Children’s, we treat patients with FAI ranging in age from the early teens up to the early 40s. We treat adults with this condition because FAI starts during childhood and we have extensive experience managing it over a lifetime.

Recovery depends upon the amount of damage found in the hip joint and the type of procedure performed. After hip surgery, the patient will need crutches for one to two weeks. For teen and adult patients, rehabilitation after surgery typically involves four to six weeks of physical therapy. Exercises help strengthen the hip joint and prepare the hip to carry weight again. Individuals often return to selected activities in four to six months.

If symptoms are left untreated, FAI will cause injury to the hip socket. This can lead to more pain, decreased function and the possible development of osteoarthritis. Over time, chances that the joint will worsen quickly increase. If this happens, the patient may need a total hip replacement. With treatment, patients are commonly able to return to prior activities with less pain.

For patients undergoing surgery, the long-term results of hip surgery is very good. Both endoscopic and open surgery typically result in improved hip function with less pain in even the most severe cases. Results can vary depending on how severe the disease is and the expectations of the patient.

FAI is a leading cause of arthritis in adults and some patients may develop arthritis later in life. Others may need a hip replacement in the future, depending on how bad the FAI was at the time of surgery.