The scoliosis surgery using the Cotrel-Dubousset instrumentation is a complex three dimensional correction. This surgery was first simulated for a given patient using a personalized finite element model: the geometry was extracted from a 3D stereoradiographic reconstruction and mechanical properties were personalized using lateral bending tests. Finally, three alternative surgical strategies were simulated in order to analyze their effects on spine postoperative configuration. First results are promising and should allow surgeons to objectively analyze various strategies or techniques.