https://disneyparks.disney.go.com/blog/disney-parks-disability-access-service-card-fact-sheet/
Disability Access Service.
Helps those with disabilities get a more equal experience of the parks.
Alas, mobility issues don't qualify. A wheelchair or scooter will be expected if you can't stand/walk in lines. Just get a scooter, IMO. You're going to be *exhausted* trying to walk around like you no doubt normally do at the parks. I wouldn't do a wheelchair because your hands and upper arms aren't used to pushing yourself, and it'll get difficult for your family/friends to push you. The scooter lets you control your movement.
Is there a chance of a break? You're either driving or flying I assume; does the doctor know this and has he given his OK to a long drive or a flight? Many doctors would be worried about a blood clot happening.
Is there any chance you could go to an urgent care once in Anaheim and get that xray done? I've read that nowadays they like to let a possible break settle a bit before getting an xray, but I would worry that with walking etc at Disney you would inflame it more by the time you get back from the trip?