Whether a foot will break after being crushed by a wheel depends on very many factors, first of all on the weight of the wheel. If it is a very heavy truck, there is no doubt that it will be fractured, but if it is a very light bicycle, it will not be fractured, so it depends first of all on the weight of the vehicle involved. It also depends on the part of the body that was crushed. If it is the tip of the toe, the relative force is small and the pressure increases, so the possibility of fracture is much greater. If it is pressed into the outer 1/3 of the dorsum of the foot, which is relatively gentle, it is not easy to fracture as long as the force is even, unless the wheel is too heavy to cause a fracture.