I've had birds come home with injuries for a toss or even during loft flying. My most recent one was with my YB that I found lying down on the table in the back yard. I opened the trapped door to let it in and didn't moved so went up to it and noticed a big gash on the keel approximately 4 inches long. I had it isolated and at some point thought it wasn't going to make it. It has now recovered and slowly flying with the rest of them.