Have you tried exercises to strengthen your back muscles? I have a problem with nausea when I take pain meds so I do these exercises to get relief. They're very easy and quick to do. Hope this helps.
http://exercise.about.com/library/gr...extension1.jpg
http://www.metacafe.com/watch/193282...sion_exercise/
http://www.metacafe.com/watch/404207...shoulder_area/