Well when you bowl a Leg break delivery, the position of the wrist will be rotated from basic 0 degrees to some where at nearly 45 degrees such that the back of the palm will face the bowler.

The main intention to do this is to try and rotate the ball from right to left ( if you look at from back or opposite angle ) with the help of turning or ring finger, making sure to rotate the ball along with the seam in the direction of slip region by spinning up in trajectory style.

In googly the back of the palm will face the batsman and in Topspinner the back of the palm will face the sky during the releasing point.