Hi and welcome!
You don't say if you've tried a compression stocking, and, honestly, I don't know if that's appropriate or not. But you can't continue to work that job if it leaves you in pain every day.
I couldn't say, also, if disability is an option. If you call your local department of disabilities, they would be able to answer your questions about that. I do know of one or two PWS patients who qualify for some type of disability, but their birthmarks cover most of their bodies and require extensive treatment.
Glad you stumbled in! Other people will chime in soon, as well.