Final answer:
The iliofemoral ligament is a strong intrinsic ligament located in the hip joint. It resists hyperextension and rotation of the extended knee.
Step-by-step explanation:
The iliofemoral ligament, also known as the Y ligament of Bigelow, is an intrinsic ligament located in the hip joint. It stretches from the ilium of the hip bone to the femur, on the superior-anterior aspect of the joint. The iliofemoral ligament is the strongest ligament in the body and plays a critical role in resisting hyperextension and rotation of the extended knee.