The last bone I broke in Aikido was the fourth toe on my right foot. I moved to blend and stepped a little to quickly, catching my toe on uke's foot. There was a loud pop, I finished the technique. Sensei's reaction was simply to raise an eyebrow. Uke's action was to freak out and my reaction was to get ready to the next attack. Breaking digits is nothing new for me and unless it's through the skin it really doesn't affect me much until after class and I have time to think about it. Then I just tape it and get on with it.
When I trained in kenpo I saw/had several breaks. The worst was a collar bone (not mine). The guy got up from the tech, tried to shake it off and couldn't move the arm well. He excused himself and had his wife drive him to the hospital.