The acetabular labrum is horseshoe shaped and the ends are connected via the transverse ligament. The function of the acetabular labrum is to increase stability of the hip joint and to decrease the degeneration of the articular cartilage. With a deficient labrum the suction seal on the femoral head decreases and outwards movement of the femoral head can occur.

Gradual detachment of the labrum and the wearing down of the articular cartilage will occur with FAI. In chronic cases significant cartilage loss and arthritis of the acetabulum can result.