We report a case of a nine-year-old girl with scoliosis and Williams syndrome (WS) which rapidly progressed to 75' and required surgical stabilization. Common features of WS include elfin face, mental retardation, and supravalvular aortic stenosis. Orthopaedic manifestations are hallux valgus, little-finger clinodactyly etc, not to mention scoliosis. Spine surgeons should be particularly careful of scoliosis due to the possible rapid progress of WS.
