I have never owned 1 but do no people who have had it done and dogs where great, also peoople have left it without any major probs other than when the dog runs sometimes its a hop skip n jump action till it pops back into place.
Its very common in mini short legged breeds, I would probs wait till she is 12 months then reassess as long as there is no sign of muscle wastage or obvious discomfort. She probs wont grow much bigger now but u never know that extra milimeter might make a difference