I have a friend who uses oregano oil all the time for arthritis and rheumatism symptoms in her hands. This oil is mixed in a cream that she applies to her hands every night and morning, with oregano oil being one of the main ingredients.
She says that if she goes a few days without applying this cream, her hands get very stiff and she can really tell a difference.
I have read that oregano oil is very strong and used for many different conditions. I figure if you have those kind of results from using something natural, then you have nothing to lose by giving it a try.