What Is Old Man's Disease. A Male Relative Has It.

What is old man's disease. A male relative has it. He has extreme pain. He has been on steroid medication for years. He takes a lot of pain medication now. He has no feeling in his hands and if he holds something he is not sure of his grip on an object. He was told that it is extremely rare, like one in a million. I am guessing that old man's disease is not the technical term. What is it? Could he possibly be helped?