Broken many bones? Certainly not! (2,2,5)
I believe the answer is:
by no means
'certainly not' is the definition.
(I've seen this before)
'broken many bones?' is the wordplay.
'broken' is an anagram indicator.
'many'+'bones'='manybones'
'manybones' anagrammed gives 'BY NO MEANS'.
(Other definitions for by no means that I've seen before include "Certainly not, not in any way" , "Definitely not" , "Certainly not, perish the thought" , "Without using any method" , "Forbids" .)