I highly recommend a "ton kooiman" pro model thumb rest. I have no affiliation with the company, but have gone through a lot of problems with my right hand. The device is a detachable thumb rest that shifts the weight of the oboe to closer to your hand (makes it feel lighter) and rotates your hand in relationship to the instrument, keeping your wrist straighter, allowing more freedom of movement, and keeping stress off the tendons of the hand, wrist and elbow. If you want to try it, go ahead and get the pro model - the student one is made of plastic, isn't detachable, and is generally not much help in my experience.
I had a ton of tendonitis/nerve problems in my right hand during my undergraduate work, and I switched to this device out of desperation. To read what I went through and see if there's any similarity, those posts were under "hautboismusique". I lost my login information, so "otterhounds" is now my new screen name - sorry. Anyway, it was the best move I ever made - my technique is cleaner than ever and lighting fast now that I've learned to work with the new orientation. Though, I wouldn't put it on right before anything majorly significant (recital, auditions, etc). It took me about a month/month and a half to get it adjusted to where I like it (it can move basically anywhere you want it)
Feel free to contact me if you'd like. Best of luck with your hand problems.