Treadmill vs Running outside after injury

A runner who has been recovering from a plantar plate sprain was on a webcam call just to follow up and ask me some questions about her first runs now that she is returning to running.
 
She wanted to know whether or not she should be running on a treadmill or running outside if there was any advantage or disadvantage to either. 

Which is better when you are returning to running after an injury, running on a treadmill or just running outside? 

Well, that is a great question and that is what we're talking about today on the Doc On The Run Podcast.