Difficulty moving head after small contretemps (9)
I believe the answer is:
stiffness
'difficulty moving' is the definition.
(stiff can mean having difficulty moving)
'head after small contretemps' is the wordplay.
'head' becomes 'ness' (type of geographical point).
'after' is a charade indicator (letters next to each other).
'small' becomes 's' (abbreviation - e.g. clothes size).
'contretemps' becomes 'tiff' (a contretemps is an argument or altercation).
's'+'tiff'='stiff'
'ness' after 'stiff' is 'STIFFNESS'.
(Other definitions for stiffness that I've seen before include "Formality" , "Inflexibility" , "Rigidity" .)