Looking for an opinion on a question I have from Dantes Inferno.?

In the early part Dante runs across fortune tellers whose heads are spun backwards since in life they had to look forward so now they can't see in front of them. What exactly is supposed to happen if they just start walking backwards? I mean I just read a synopses so I don't even know if it is covered in the play. But seriously, what happens with loopholes in hell?