Hi...roller coasters can trigger dormant symptoms...so, u may want to avoid activities that may cause u distress or strain.
The herniation can grow, but, it is not the length that is most important as many drs feel....many with a herniation smaller than 5mm can have worse syptoms than someone with a larger herniation, Width of the tonsil is important too as it can block CSF flow and that is very important. Over crowding is another issue u need to find out if u have.
Find a true chiari specialist to help u get the proper care.See our list of chiari drs to help u research to locate the dr right for u.The list is not intended as a referral.
http://www.medhelp.org/posts/Chiari-Malformation/LIST-OF-CHIARI-SPECIALISTS/show/1293483
"selma"