got me a paper from 1978, so I guess it's not new untried technology?
This is all media oriented, but...
http://uscspine.com/treatment/steroid-injections.cfm

This is also fairly recent:
http://www.ispub.com/ostia/index.php...n1/steroid.xml

Not the answers you want but, possibly starting points?

I guess it comes down to: which pain came first? Pain A or Pain B?
Which pain is worse? Pain A or Pain B?
Oh for a new pain vocabulary!
Good thoughts - j