Sorry your arm/elbow is so painful, and hope you can get some relief from whatever treatment is offered. Whenever I've had to take steroids, they really raise my blood sugar unfortunately. It would obviously depend on the dosage and how long you were on them, as sometimes quite short courses are prescribed. Steroid injections are another option, but again they raise my blood sugar. They may affect you differently of course, but I think in general they raise blood sugar. Sorry, I know this isn't what you wanted to hear.