Femoroacetabular impingement

Femoroacetabular impingement (FAI) is a condition involving one or more anatomical abnormalities of the hip joint, which is a ball and socket joint. It is a common cause of hip pain and discomfort in young and middle-aged adults. It occurs when the ball shaped femoral head contacts the acetabulum abnormally or does not permit a normal range of motion in the acetabular socket. Damage can occur to the articular cartilage, or labral cartilage (soft tissue, ring-shaped bumper of the socket), or both. The condition may be symptomatic or asymptomatic. It may cause osteoarthritis of the hip. Treatment options range from conservative management to surgery. Pain is the most common complaint in those with FAI. It is experienced in a number of areas, making the diagnosis challenging, but commonly occurs in the groin, upper buttock/lower back, the buttock or beneath the buttock, side of the affected hip and posterior upper leg. Onset of symptoms has been reported to present in both an acute and more gradual manner. The pain is often significant enough to cause a decrease in activity level and movement. Some will also describe decreased range of motion of the affected hip. Another symptom is groin pain associated with activity and no prior history of trauma. Inability to perform activities such as high hip flexion or prolong sitting can also be seen in individuals with FAI. FAI is characterized by abnormal contact between the proximal femur and rim of the acetabulum (hip socket). In most cases, patients present with a deformity in the femoral head, or acetabulum, a poorly positioned femoral-acetabular junction, or any or all of the foregoing. The cause of FAI is currently unknown, but both congenital and acquired etiologies have been put forth. Studies have shown an increased incidence in siblings, suggesting a genetic component. At least one study has also shown a predilection in the white population. It has also been reported to be more common in males.