Femoroacetabular impingement (FAI)

It's a condition when the femoral head and acetabulum rub against each other creating damage and pain to the hip joint. The damage can occur to the articular cartilage (the smooth white surface of the ball or socket) or the labral tissue (the lining of the edge of the socket) during normal or extreme ranges of movement of the hip ultimately leading to increased risk of arthritis.

There are 2 types of FAI 

CAM-Type impingement: when the femoral head and neck are not perfectly round with a prominent bump. This lack of roundness and excess bone causes abnormal contact between the surfaces.

PINCER-Type impingement:  when abnormal extensions of bone from the edges of the socket protrude out (like the pincers of a crab) and abnormally contact the head and neck (“ball part”) of the joint causing pain and damage to the neck of the joint.

Symptoms include sharp groin pain, clicking or catching sensation, pain after prolonged sitting or walking. Diagnosis includes medical history, physical examination, and diagnostic studies including X-ray, MRI, and CT scan. Local injections into the hip joint with a local anaesthetic may be needed to confirm the source of pain prior to surgical interventions.

Treatment: included conservative management with rest and activity modification. Open or keyhole surgery to remove the excess bone or repair the damaged labrum. Arthroscopic femoro–acetabular surgery for hip impingement syndrome should only be carried out by surgeons with specialist expertise in arthroscopic hip surgery.