Joint strain for sewer (10)
I believe the answer is:
seamstress
'sewer' is the definition.
(I've seen this before)
'joint strain' is the wordplay.
'joint' becomes 'seam' (seam is a kind of joint).
'strain' becomes 'stress' (synonyms).
'seam'+'stress'='SEAMSTRESS'
'for' acts as a link.
(Other definitions for seamstress that I've seen before include "Woman who sews for a living" , "sewer" , "Dressmaker" , "needlewoman" , "Midinette" .)