Doctor not sure cutting into wound is common sense (8)
I believe the answer is:
gumption
'is common sense' is the definition.
(I've seen this before)
'doctor not sure cutting into wound' is the wordplay.
'doctor' becomes 'gp' (general practitioner).
'not sure' becomes 'um' (both might be said when unsure about something).
'cutting' indicates putting letters inside (some letters cut their way into a word).
'wound' indicates an anagram (wound can mean twisted or turned around).
'gp' going around 'um' is 'gump'.
'into' is an anagram of 'tion'.
'gump'+'tion'='GUMPTION'
(Other definitions for gumption that I've seen before include "Courage needed!" , "Fortitude and determination" , "Informal drive and initiative" , "Informal common sense or initiative" , "To impugn (anag) - common sense" .)