Fig. 1
The coordinate graph (an x–y plot) for eccentric distance (ED) calculation of the cephalic fixator tip in the femoral head. No matter how big the radius of the femoral head (RFD) was, we assumed the RFD as “3” (RFD = “3,” without any unit) for good match of Cleveland zone system and easy calculation. ED of the cephalic fixator tip (x, y) is the distance from the circle center to the tip point of (x, y)