Broken rule again produces intermittent pain (9)
I believe the answer is:
neuralgia
'intermittent pain' is the definition.
(I've seen this before)
'broken rule again' is the wordplay.
'broken' indicates anagramming the letters.
'rule'+'again'='ruleagain'
'ruleagain' is an anagram of 'NEURALGIA'.
'produces' is the link.
(Other definitions for neuralgia that I've seen before include "Shooting pains" , "illness" , "Pains in the neck" , "Pain from damaged nerve" , "intermittent pain" .)