You might consider seeing an expert chiropractor that also does upper cervical adjusting.
Your c1 c2 may have gotten misaligned from the crash - MDs don't really explore this part of things. Some type of bias I suppose...

info-
http://www.upcspine.com/self.htm

Or you may have acquired a version of thoracic outlet syndrome..
http://neurotalk.psychcentral.com/thread84.html

But I would seek out expert chiro first and see where that goes for you..