Hi Oscar,
Just from what you describe of your injury and history, i wonder if you might have some aspects of thoracic outlet syndrome along with your C spine problems.
I'll give you the link to the TOS forum and our sticky with useful sites and info- the anatomy and dermatomes info will be helpful for you also.-
TOS forum
http://neurotalk.psychcentral.com/forumdisplay.php?f=24
useful sticky-
http://neurotalk.psychcentral.com/showthread.php?t=84