Progressive asymmetry of the pelvis is frequently observed in total body involved cerebral palsy (CP) children, when opposite contractures and deformities affect the two sides of the body. This asymmetry is important in terms of difficulty in standing and seating stability and if untreated can lead to bilateral dislocation of the hip. The visual term “Windsweep” has been used to describe this deformity. We present an equation to determine the extent of this asymmetry - the “Windsweep” Index (WSI). This can be used as a numerical assessment of the deformity and to assess the efficacy of treatment.
