larqw wrote:The legs can move, but she doesn't put pressure on them or use them

She's probably got a sprained limb. The only reason I suggest this is because I have seen it with my turtles many years ago when I had 2 in the same tank (Sheba & Nelson). Touch the arm of your turtle, and feel if it is broken (see if it will move in the direction that it is supposed to). If it is swollen or if you feel anything unusual, take the turtle to the vet.
One thing I will tell you about turtles & sprained limbs: if it is broken or sprained, the vet will not be able to put a cast on it anyway. A vet told me many yrs ago when it happened to one of my turtles that keeping the turtle in the bouyancy of the water would help (don't let them use the arm for about 2 weeks). Swimming is fine, climbing or walking on land is not. This will help alleviate the stress on the joints. If they don't bask for a couple of weeks, it won't hurt them. But you have to give the joint a chance to heal. Even after the 2 week period, they may still use the limb very gingerly, but they will have to build up strength in it so it should be ok to use at that point.