Ankle injury (6)
I believe the answer is:
sprain
'ankle injury' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for sprain that I've seen before include "Wrench, the ankle say" , "Pull" , "Wrenching (of a muscle)" , "Twist ligament(s)" , "Wrench, dislocate" .)