Theatre operative attaching end of arm to leg (9)
I believe the answer is:
stagehand
'theatre operative' is the definition.
(someone who moves the scenery in a theatre)
'end of arm to leg' is the wordplay.
'end of arm' becomes 'hand' (a hand is on the end of an arm).
'to' says to put letters next to each other (I've seen this in other clues).
'leg' becomes 'stage' (synonyms).
'hand' put after 'stage' is 'STAGEHAND'.
'attaching' acts as a link.
I am not very happy about this link. It may belong to another bit of the clue.
(Other definitions for stagehand that I've seen before include "One may move flats" , "Person moving theatre props" , "General helper for play, moves scenery etc" , "being responsible for properties" , "Theatre employee" .)