Figure 3

The original classification according to Lehnert-Schroth. On the left the Three Curve Pattern with the shoulder, thoracic and lumbo-pelvic block deviated against each other in the frontal plane and also rotated against each other. On the right the Four Curve Pattern with a separation of the lumbo-pelvic block into a lumbar and a pelvic block deviated against each other in frontal plane and also rotated against each other. Per definition: the pelvic block symbolises the lumbosacral counter curve and this curve is defined as the 4th Curve [12].