M.M.
My DD broke her leg at 2. Not along the growth plate, but she was in a cast for 6 weeks. (vertically fractured tibia)
She was jumping around before the end of that 6 weeks, so no need for being extra careful after it was off. It took her a day or two to adjust to not having it on, and then it was like nothing ever happened.
My advice is that if the ortho isn't worried about it, you shouldn't be either.