Figure 1

Lateral Profile Analysis derived from Rasterestereographic data. Outline of the sagittal profile. Three inflectional points along the profile are marked by open circles – the cervicothoracic (ICT), the thoracolumbar (ITL) and the lumbo-sacral inflection point (ILS). The tangents to the inflectional points span two characteristic angles of the profile – the kyphotic angle (KA) is spanned by the tangent lines in ICT and ITL; in an analogous way the lordotic angle (LA) is spanned by the tangents in ITL and ILS. Two other angles provide orientation data with respect to the vertical line (plumb line); 1) the angle of the upper thoracic inclination (UTI), which is virtually the angle spanned by the vertical and the ICT tangent, 2) the angle of the pelvic inclination (PI), virtually the angle spanned by the vertical and the tangent ILS