Faces surgery needed by models (7)
I believe the answer is:
opposes
'faces' is the definition.
(opposing is a kind of facing)
'surgery needed by models' is the wordplay.
'surgery' becomes 'op' (short for operation).
'needed by' says to put letters next to each other.
'models' becomes 'poses' ('pose' can be a synonym of 'model').
'op'+'poses'='OPPOSES'
(Other definitions for opposes that I've seen before include "Stands against" , "Goes against" , "Disagrees with and attempts to prevent" , "Counters" , "Strongly disapproves" .)