People who live inside the world's many war zones, from Afghanistan to Rwanda, may never have heard of New York or Paris, but they are likely to know of a town in northern India called Jaipur. Jaipur is famous in strife-torn areas as the birthplace of an extraordinary prosthesis, or artificial limb, known as the Jaipur foot, that has revolutionized life for millions of land-mine amputees.
The beauty of the Jaipur foot is its lightness and mobility--those who wear it can run, climb trees and pedal bicycles--and its low price. While a prosthesis for a similar level of amputation can cost...