Iliofemoral ligament

The iliofemoral ligament (Y-ligament; ligament of Bigelow) is a band of great strength which lies in front of the hip joint; it is intimately connected with the joint capsule, and serves to strengthen the joint by resisting hyperextension.

It is attached, above, to the lower part of the anterior inferior iliac spine; below, it divides into two bands, one of which passes downward and is fixed to the lower part of the intertrochanteric line of the femur; the other is directed downward and lateralward and is attached to the upper part of the same line.

Between the two bands is a thinner part of the capsule.

In some cases there is no division, and the ligament spreads out into a flat triangular band which is attached to the whole length of the intertrochanteric line.

Its upper band is sometimes named the iliotrochanteric ligament.

Flexibility of the ligament required in order to achieve the turnout used in the classical ballet style.