My husband is 74 years old, and he fell at home and fractured badly, his hip. He had surgery the next morning and a rod was put from the hip down to his knee. When he bends his knee, just a little, where the screw is, creaks, and it hurts him all the time. Why would a rod have to be put all the way from the hip to the knee?? And why would it creak, when moved?? thank you!