I have worked with several high school kids this month that have suffered concussions affecting their visual system.  We've actually got to release 2 kids from therapy this week which means they are returning to their medical doctors for a possible return to play (or, in one instance, return to cheer!)...I guess that I would also add that I have worked with 2 cheerleaders this summer (fliers) that came down and hit their chin or heads to the base's shoulders. It's lead me to believe that cheerleading is definitely on the top of the list for roughest sport.