Spinal decompensation after selective thoracic fusion by using 3 dimensional corrective devices especially in type 2 curves has become a severe complication secondary to progression of the unfused curve. İn this article we evaluate ourpatients and propose some criteria in order to prevent decompensation, lumbar kyphosis and junction-al kyphosis. We concluded that the King criteria for three dimensional correction of idiopathic scoliosis are not ap-propriate
Keywords: İdiopathic scoliosis, Spinal decompensation, Corrective forces.