Carpal tunnel syndrome can cause pain that extends up the arm towards the shoulder as it gets worse
I suspect that you use your hands a lot at work? the swelling may be some associated bursitis(swelling of the fluid around the muscle-bone attachments) for the same reason
I cannot tell you for sure as I have not examined you or seen your EMG results
MRI and EMG should be able to exclude a problem in the nerve rots at the neck or in the spinal cord
If the last EMG was last June, it would be worth repeating to see if it is worse, or is serious enough to consider surgery
Good luck!
PW
I too had symptoms that were varied and would occasionally come and go, and since you said resting helps a little, it sounds like your problem is more related to movement or that it is aggrivated by movement. I hurt all the time but was definetely worse with movement, standing, or even sitting in a chair (I also worked with a computer). Proper diet and excercise are also usually beneficial to overall health and wellness. Pilates workouts have helped immensely with training the muscles in my body to maintain correct posture which relieves quite a bit of pressure on my spine and will help to hold my atlas in place. Its sometimes hard to believe that such simple things can help such extreme conditions but barring actual injuries (ie. torn or broken parts of the body), diseases, or other noticeable and definite problems, these things can help. Check it and a UPPER CERVICAL SPECEFIC CHIROPRACTOR out. I know from experience that its hard to be patient but hang in there. I'll pray for you.