If you get a fracture of the metatarsal, you have to make sure that it's healed before you start running on it. 

It doesn't matter if it's a stress fracture, or a traumatic fracture where you stepped in a hole, tripped or fell off a ladder. 

Deciding when it appears to be healed enough to withstand the forces of running is the key.

The most common way doctors decide when the fracture is fully healed is by taking an X-ray.