Fig. 2From: The migration percentage measured on EOS® standing full-leg radiographs: equivalent and advantageous in ambulant children with cerebral palsya represents Hilgenreiner’s line, a horizontal line connecting both tri-radiate cartilages. b represents Perkin’s line, a vertical line drawn at the lateral margin of the acetabulum perpendicular to Hilgenreiner’s line. The Migration Percentage is defined as the percentage of the femoral head situated lateral from Perkin’s line. It equates as ‘a/b’ with (b) representing the calcified femoral head at its widest point and (a) representing the part of (b) lateral from Perkin’s lineBack to article page