I have RSD in my upper body, and I have polyneuropathy, mine is called painfull small fiber neuropathy, in my lower body.
My dr seemed to be happy for me it was not the RSD spreading to my feet after the QST -Quantitative sensory test which told her what was going on in my feet's
The RSD is "complex"- because it is affecting blood, skin, muscle the sympathetic nervous system which controls our internal system"- and what we feel all the time PAIN.
The pheripheral neuropathy is painful or to some numbness or no feeling at all. And it can be diabetic- check your sugar-levels. It can be lack of B12- have you had this checked? And Gluten-intolerance (Celiaki?) And for me it is probarly from hypo-thyrodism.
And yes RSD can spread from ice due to vasoconstriction and sympatethic something, I am not a DR., but have read alot and do not remember it all,sorry.
My feets is oversensitiv to cold, and this is from the destroyed small fiber nerves. So you see there is a difference here.
Hope some of this make sence to you
I can't really tell you what it is in your situtuation, but do the research and ask your dr's.