Prince is apparently to have hip surgery because he's spent his life wearing far too many high heeled shoes. He is allegedly chary about the idea because of his religion. As you know, the diminutive star is a Jehovah's Witness, which means he can't have a blood transfusion.
Of course, it may be complete rubbish. But a no doubt extremely reputable source told the never-scurrilous National Enquirer: "Over the years he has battered his body so much that his joints, especially his hips, are causing him a lot of discomfort."