<prompt> All of the following are types of avascular non-union except:ComminutedElephant footTorsion wedgeAtrophic  <response>: Classification of non-union: Hypervascular non-union:Elephant foot hypertrophic , rich in callusHorse foot mildly hypertrophic , poor in callusOligotrophic non-hypertrophic, no callusAvascular non-union:Torsion wedgeComminutedDefectAtrophic 