Fig. 27
From: Brace technology thematic series: the 3D Rigo ChĂȘneau-type brace
![Fig. 27](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs13013-017-0114-2/MediaObjects/13013_2017_114_Fig27_HTML.gif)
Classical double structural scoliosis, main thoracic/lumbar (apex L2) or low thoracolumbar (apex L1) is the most common 4C compatible curve pattern. This is called B1 type. It can be double major, major lumbar-low thoracolumbar/minor thoracic, or rarely major thoracic/minor lumbar-low thoracolumbar. The second radiological criterion is the TP (and T1) offset to the concave thoracic side according the CSL. A third criterion is the L4âL5 positive counter-tilting. It can be combined with a structural proximal thoracic curve (triple structural scoliosis)