The postural component of scoliosis . A scoliosis curve is made of many different components, including a postural one. Duval-Beaupére  described the case of three different radiographs: standing (SR), lying down (LR) and in correction e.g. using a cast (CR). The structural bony component can be measured with the CR; the structural ligamentous component comes from the difference between LR and CR; the postural component from the difference between SR and LR.