11 Year Old Girl With Hypoplasia Of The Right Side

11 year old girl with hypoplasia of the right side of her body: shorter and smaller upper extremity, shorter and smaller right lower extremity, with what appears to be s/p left hip displasia, limited external rotation of left hip. I have seen patients with what is described as Poland's syndrome, I have seen results of coarctation of aorta, but this is first time seeing hemihypoplasia. Is there some genetic/ developmental pattern, other medical condition underlying this?