A teenager, brutally attacked by a shark six years ago, lost his leg and thought he might never walk again; but Craig Hutto persevered. For the last several years, Hutto has been working with Vanderbilt researchers to develop a truly revolutionary bionic leg. In this Video News Release, Vanderbilt reporter Barb Cramer tells us the unique design of the fully-powered ankle and knee may offer hope to 300,000 above-the-knee amputees in the U.S., and more than a million world-wide.