Oh yes , unfortunately difficult to prove unless you have very good drs & wc atty on your side.
mainly because TOS does not clearly "show up" { aka the proof in wc view} on the standard & usual tests.
be prepared for possible denials, appeals and stall tactics.
If you have/find a good dr that understands accumulated injuries and will stand strong against the IME drs and the wc case workers you have a better chance.
The worst part is the delay and stall tactics- you could be getting some decent PT/therapy that can turn things around right at the start and sometimes they drag it out and try to keep you working - which increases the damage and the PT treatments cannot get ahead of the injury if you are still using/working. {my honest opinion}

You can use the forum search tool to find how other here deal with wc or any specifics, symptoms, etc
http://neurotalk.psychcentral.com/fo...to_forumsearch
Our workers compensation forum has good info in the stickys there-
http://neurotalk.psychcentral.com/forum30.html

questions wc and atty will ask about-
was he healthy and active until these sx came on ?
after how many yrs of that type of work?
did any specific event set it off at all?
any hobbies or activities that might cause these symptoms/injury?

I can totally agree about handling papers - they had me do that for modified duty- it was almost as bad for me as the doing my normal job.
{the pinch, grip, wrist rotations and carrying papers and notebooks, filing papers in a over full file cabinet}