Fig. 2From: Relationship of muscle morphology to hip displacement in cerebral palsy: a pilot study investigating changes intrinsic to the sarcomereQuantification of hip displacement (subluxation or dislocation) by migration percentage (MP) for children with cerebral palsy. MP is validated measure calculated through a ratio of the extent of the femoral head lateral to the edge of the acetabulum (delineated by the vertical Perkin’s line shown) divided by the diameter of the femoral head. The measurements should be parallel to the horizontal Hilgenreiner’s line shown (a line connecting the superior aspects of the triradiate cartilages)Back to article page