Shake injured leg after run (6)
I believe the answer is:
joggle
'shake' is the definition.
(joggling is a kind of shaking)
'injured leg after run' is the wordplay.
'injured' is an anagram indicator.
'after' means one lot of letters go next to another.
'run' becomes 'jog' (jog is a kind of run**).
'leg' anagrammed gives 'gle'.
'gle' after 'jog' is 'JOGGLE'.
(Other definitions for joggle that I've seen before include "joint" , "Shake" .)