Turn back briefly, getting stuck in this? (3)
I believe the answer is:
rut
'getting stuck in this?' is the definition.
(as in being stuck in a rut)
I don't understand how the remainder of the clue works.
(Other definitions for rut that I've seen before include "Groove worn by wheels" , "Furrow made by wheels" , "Grove you should not remain in" , "Fixed (and tedious?) course" , "Groove made by wheels" .)