Risks of PRP vs Cortisone injections for Hallux Rigidus

I was just on a call with a runner who has had this condition called "hallux rigidus."  and it's where your big toe joint starts to get stiff, becomes rigid, and it doesn't move as much.
 
Hallux rigidus is a progressive condition, especially if you continue to irritate the joint. You can damage the joint cartilage. The stiffer the big toe joint gets, the more pressure on the cartilage when the big toe is trying to fight that stiffness. Sometimes that movement hurts.
 
He was asking me about the options on different injections.
 
What are the risks between an injection like a PRP or platelet rich plasma injection versus something like a cortisone injection when you have hallux rigidus? 
 
Well, that's what we're talking about today on the Doc On The Run Podcast.