No Cast on FX, Why?

I also have recently fractured my distal femur, and I am wondering if anyone here can tell me why I am not in a rigid cast? I have a dressing on the hip and a dressing where the screws were inserted, and was wrapped with a tensor, but that's it. Also, will the hardware be removed or is it there to stay? Any info you can pass along would be great, including websites re: rehabilitation and expected length of recovery.
Thanks.