our useful sticky thread on the thoracic outlet forum has links that will help with repetitive strain problems too.
post #1 has the most concise list of links -
http://neurotalk.psychcentral.com/thread84.html
overall posture and upper body is very important too.
the head , neck and shoulders - if rolled or forward of the main body lines it can cause strains and compressions on the blood flow & nerves that travel thru the neck, collarbone & armpit areas.