If it's cubital tunnel syndrome or some form of ulnar neuropathy, you might need a different form of support for your arm like an elbow brace. The ulnar nerve runs along the arm differently and usually the pinky and ring hurt the most. When I wore a wrist brace when I thought I had carpal tunnel syndrome instead, it actually hurt me more because it was messing with that nerve. Doctor after doing some tests confirmed an ulnar injury and told me stop wearing the wrist brace, recommending wearing an elbow brace and I should wear it when I work.

It's a bit more flexible depending on your type of injury since there's many types of elbow braces. If possible and within budget, you should try to get some more tests or a diagnosis (if you haven't already) to make sure it's what you think it is so you don't take the wrong precautions. You might actually be fine with a wrist brace rather than getting an elbow brace for your condition, you might need a specific type of elbow brace, or if it's within budget, a few more tests such as an NCV or an ultrasound to see what the fuck is wrong with your shit for a more definitive answer.

This one is more the generic advice that anybody can say but do specific strength building exercises and stretches. If you're using armrests, stop using them and work on bettering your ergonomics such as your posture or how you type. This one is not directly related to arm and wrist shit but I started using a voice recognition software for the times I don't need my hands; it's slower, frustrating and counter-intuitive compared to if I bought Voice Attack and programmed some macros (which I might do), but it helps.

I would occasionally get pain like this - the big change for me was making sure that when I slept I didn't pin that elbow under my body. The biggest influence over it wasn't the constant gaming it was that I was burying my right elbow in my mattress and pinning it under my body and putting tons of pressure on it after having gamed all day lol. Fixed that and the pain went away.

It's not a fix all and may not be pertinent in your case but it's worth a try.

I have a friend who uses his girlfriend's sock with a few holes cut out as a wrist brace, apparently it works quite well for him. I think you have to use a sock that's tight on your hand so that it actually provides support though.

not the answer to your question, but you should use an ergonomic mouse at work if you aren't already. could probably get your employer to pay for it if you demonstrate a medical issue.