Pains one gets after the operation (8)
I believe the answer is:
stitches
'pains' is the definition.
(stitch is a kind of pain)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for stitches that I've seen before include "Sews" , "As made by 35 across" , "Sharp spasms of pain in the side" , "Spasms of pain, caused by needles?" , "Sharp pains in the side caused by running" .)