I don't understand this photo of Kate Moss

Some British gossip rag put out this photo of Kate Moss jogging somewhere (in a hideous outfit if I do say so myself). It's supposed to be a really jarring display of what drugs and alcohol can do to a body.

What I don't get is how only ONE of her legs is like that. And seriously, that looks like a really gross geriatric leg, so how could it only be her left one?

Riddle me that.