[LimaFoxrot]

So, to quote Wiki, "Most contortionists are categorized as either "frontbenders" or "backbenders", depending on the direction in which their http://en.wikipedia.org/wiki/Spine_(anatomy) is more flexible. Relatively few performers are equally adept at bending both frontwards and backwards."

I don't think that makes it impossible for you to bend both ways, you might just find that front bending moves are aways more challenging. If it's any consolation, I'm the opposite. My backbending flexibility is crap.