It's funny but pain doesn't do it. I tore up my knee 3 months ago (ACL 2x femur fracture, double minscus). You cannot imagine the pain- I could not speak and almost passed out but I had no urge to cry. Now when Mulan's father expresses his love for his cartoon daughter after she saved China to earn his respect... I'm verclempt.
I suppose it depends, fortunately I haven't been hit in the balls since I was 18, and then he only winged me with a football.