Should i let the ASPSA fix my kitten?

My 5 year old sis was opening a door and accidently hit my kittens leg. She didnt hit it hard but the kittens leg started hurting and it started limping. It doesnt walk on its hind leg much. I beleive its dislocate, sprained or even broken. But my family cannot pay for the vet bills for they cost from $100-1000. So we wer thinking of turning it into the ASPSA for them to try and deal with the problem. I heard its sometimes free and costs less there. But im afraid theyll take it away from us, because my sis accidentally hit it with a door. And charge us with cruelty?? Is that possible to happen?? I just really want to help my kitten, hes only 2 months!! :(