Fibula stress reaction vs stress fracture what is the difference?

If you have ankle pain and you push around on that lump of bone on the outside of your ankle, you may realize that you have pain on the bone specifically.  

If so, you might become worried that you have a thing called a fibular stress fracture.
 
If you start trying to figure out what to do, one of the first things you may find is a lot of discussion about something called a "stress reaction" instead of just a "stress fracture". 
 
What's the difference between a fibular stress reaction and a stress fracture in a runner? 
 
Well, that's what we're talking about today on the Doc On The Run Podcast.