Hey, Brandy! I am so sorry to hear about your son! I am sure he is a bit disappointed to have to be in a cast while visiting Walt Disney World Resort, but I have some great news to share with you. He will be able to ride pretty much every attraction while at the theme parks! There is only one possible exception I can think of - Avatar Flight of Passage at Disney's Animal Kingdom Theme Park. There are two sets of restraints on each ride vehicle. One piece of it comes up behind your back, while the other set comes up behind your calves. Those restraints do not lock into place if they are not able to come forward a required distance. However, it may actually work for him. There is a test vehicle found right outside this attraction's entrance where your son can climb aboard and see if the restraints will work before you hop into the line.
There are no other attractions that have
mobility requirements that would affect him, but he may find it a bit awkward to climb out of ride vehicles at some attractions. I broke my ankle a couple of summers ago just days before a trip I took with my sister and was in a walking boot. It was definitely an experience climbing in and out of the Space Mountain and Rock 'n' Roller Coaster vehicles! If your son is in a hard cast, you may want to bring along a bag to put over it while riding Splash Mountain and Kali River Rapids.
Have you made a plan yet for helping him get around each day? Walt Disney World Resort is a HUGE place and you will be doing a lot of walking. I just looked at one of my phone apps, which logged me as taking between 15,000 and 19,000 steps each day during a recent visit! I am not sure of your son's age, so his options may be limited. The best bet may be to
rent a wheelchair for him, which can be done at the front of each park.
Feel free to stop by again if you have any other questions about your upcoming visit!
Brandy