Prosthetic limbs are being designed to look like a human foot so wearing a shoe over it isn't a problem. The problem is that the current ones can't accomodate a traditional shoe. Nike invented a new one.

The shoe is called Sole, and the minimal design was meant to slip onto Össur's Flex-Run prosthetic
blades which are used by competitive athletes. Triathlete Sarah Reinersten helepd Nike co-develop the product.

Sole is composed of an outsole, midsole and a specially designed material called Aeroply which will allow the sole to grip the carbon fiber of the prosthetic blade while the athlete is running.

Sole is available now, presumably from prosthetists' offices who also carry Össur's Flex-Run blades. [designboom]