I don't know that it is a treatment??
I think more of a diagnosing tool.
Also have seen it mentioned for CRPS/RSD dxing.

[A stellate ganglion block determines if there is damage to the sympathetic nerve chain and if it is the source of arm pain.]
http://www.spineuniverse.com/exams-t...ganglion-block

more -
http://www.google.com/search?hl=en&c...+Block&spell=1