While most of us have had a shattered bone at some time in our lives, the truth is that bone is a very tough substance. So powerful, in fact, that "ounce for ounce, human bones are stronger than steel," as Discover Magazine puts it. A bone has a higher pressure tolerance and bearing strength than a steel rod of equal width. The femur is the strongest bone in the body, capable of supporting 30 times the weight of an ordinary adult. We all are men or women of steel...