pelvic bone, which sucks because there's tons of nerve endings in there. it's super painful. >> you've been hurt a lot, i assume? >> yeah. i've had tons and tons injuries. i train really, really hard. accidents happen and you recover and you heal and, you know, you start again. >> at least you don't have balls. >> at least i don't have balls. exactly. there's always a plus side to every situation. >> exactly. in a violent combat sport, injuries pose a constant threat to a fighter's career. hannah knows the risks involved and has chosen to put herself on the line. but mma fever has spread beyond ranks of seasoned athletes. even children are now taking up the sport. critics call it kids cage fighting.