What Causes Numbness Of Limbs?

I'm a 36 year old white male. My left leg goes numb between my hip to just above
my knee and there are no other symptoms like pain or anything else. It goes numb
whether I'm sitting,laying down, or standing up. The only way to wake it up is
to walk around for a few minutes. The only time it doesn't go numb is also when
I'm walking. What could be the problem? I don't have money for a doctor or
insurance, so is this something that I should go to the er for?
James Marcum