Doreen's dislocated back (7)
I believe the answer is:
endorse
'back' is the definition.
(back can mean to support or endorse)
'doreen's dislocated' is the wordplay.
'dislocated' is an anagram indicator.
'doreens' anagrammed gives 'ENDORSE'.
(Other definitions for endorse that I've seen before include "Docket" , "Affirm" , "Say you approve" , "Champion" , "Red ones (anag.)" .)