Well you only gave us one pic. But to me her legs do not look that long. What does look *off* to me is her right front leg at the elbow - a thickening of the joint there. Also in that pic her back is roached. That means bowed upward. This could just be an unfortunate picture or angle that the pic was taken. And btw *knobby* joints can be quite common in young pups.
A pup that small is not something I would select, but it is great that there are folks willing to take the extra care that their small size requires
