Fig. 14.

The sagittal configuration of the scoliotic spine is too variable to be simplified with simplistic “dogmas” and solutions, like “scoliosis is a flat back deformity” or “scoliosis comes from a kyphotization of the thoracolumbar spine.” The low thoracolumbar curve observed in a (apical vertebra L1) presents indeed a thoracolumbar kyphosis in the lateral projection, but the second one (b), with much less torsion, shows a still full lordotic configuration in the lateral projection. The very low thoracic curve observed in (c) is associated with a proximal thoracic curve and a distal short lumbar curve. The projection of this last scoliotic spine is clearly lordotic at the thoracolumbar region. Junctional thoracolumbar kyphosis is most commonly observed in true double major thoracic/lumbar curves. A torsional phenomenon rather than a single uniplanar failure can explain the high variability of sagittal configurations observed in relationship with the frontal curve pattern