physiobob,

thanks so much for the response. although you said it sounds complex, it does make sense. I've thought it could potentially be a brachial plexius problem too. My only questions would be 1) i havent thrown a baseball in 3 months, so wouldn't rest from that cause some relief? 2) what type of rehab would be involved in correcting this problem? 3) what test (Wikipedia reference-linkMRI, etc..) would help to confirm that the brachial plexus and not the neck is the issue? thanks again.