Femoroacetabular impingement (FAI)

Hip joint is formed of two bones – head of the femur and acetabulum of the pelvis, which fit together in the form of a ball in the socket. In-between there is labrum and articular cartilage to prevent rubbing bone against bone.

Femoroacetabular impingement (FAI) occurs when on one or both of hip bones there is an extra bone growing (i.e. bone spur). This causes friction between bones during movement, which can result in damaging the whole joint, tearing of the labrum, destructing articular cartilage, and, as a result, limiting mobility and entailing pain.

The reason for this condition is usually genetic, and forms during adolescence. FAI does not necessarily give negative symptoms, sometimes the affected person may not even know about it. But when disease is progressing, the patient may feel pain, stiffness and start limping, and this may indicate damage to the cartilage or labrum.

If hip pain and stiffness intensify, a patient should visit a doctor. During the consultation, the doctor interviews a patient to find out about all symptoms, way of life, coexisting medical problems and conducts special physical examination (impingement test). He can also refer a patient to diagnostics imaging tests, usually X-rays or CT scan which show abnormal bone structure, but in some cases also MRI to find out if there is damage to soft tissue (labrum and articular cartilage).

FAI can be treated nonsurgically, especially through non-steroidal anti-inflammatory medications or physiotherapy. If the symptoms persist despite nonsurgical treatment, the doctor recommends surgery. It is usually arthroscopic procedure, performed with minimal skin incisions, during which the doctor uses thin instruments and a small camera (called an arthroscope) to remove the cause of suffering which can be either damage to the labrum and articular cartilage or bony rim of the acetabulum or femoral head (pincer or cam) – or both.

Recovery time varies depending on the type of surgery. Usually the hip fully recovers within 3 months after arthroscopy, yet the wound heals after 7-10 days. The patient returns to full activity after 4-6 months, nonetheless persisting effects may be reached up to 1 year after a surgery. The doctor also recommends physiotherapy, which plays an important role in healing process.