User blog comment:AldenHeathcliffe/Chapter 551: The Burnt Offerings/@comment-1771627-20131002160132/@comment-5695542-20131002185805

@Aldenheatlhcliffe

Zanhyō Ningyō (残氷人形, Lingering Ice Puppet/Doll): Upon activating his Bankai, Tōshirō is able to create and shape a large amount of ice into his exact likeness. It is very life-like, as it can appear to bleed. He stated that he can usually only trick an opponent once with it, so he usually saves it for towards the end of a battle

http://bleach.wikia.com/wiki/T%C5%8Dshir%C5%8D_Hitsugaya#Zanpakut.C5.8D

Yeah they can appear to bleed but i would imagine there is limits on just what they can do.