I know this is a little late and you probably already have your answer but I wanted to put my 2 cents in. I had a shunt placed at 3 months old due to a cyst at the base of my brain that was causing hydrocephalus. I had it revised at 7 months and after that didn't have a problem til I was almost 17. Through out all that I was a typical kid and a total tom boy. I played softball, was a base in cheerleading(and I'll fight anyone who thinks having flying bodies coming down at you doesn't mean cheerleading is a sport!), I rode rollercoasters and bumper cars, climbed(and fell out of) trees, played full contact basketball and happened to nail my head numerous times and it was never an issue. Ironically we think(my parents and I) it ended up being cheerleading that finally did my shunt in and that was only cause the flyer sucked and I was constantly(5 to 6 times a day) getting hit in the head with a 115lb girl. Probably not the smartest thing I ever did looking back so not that I really recommend it, but basically they are meant to be tough and withstand a lot so I wouldn't really worry about a fall.