Background: Norms for measurements effectuated, among others, in the field of physiotherapy, for example, Body Mass Index or Vital Capacity % are described with regard to height (body length) of examined patients. However, in scoliosis, normally measured body length is lowered, because of the fact that the trunk length is shortened as a result of lateral spinal curvature. Given these examples, we can say that using norms for lower height will result in mistaken recognition of obesity or not recognizing restrictive type of respiratory disorder. According to that, there is a need to correct height (body length) values in order not to relate the results of examinations to lowered or overstated norms. The aim of the study is presenting method of describing real height of patients with scoliosis. Material and methods: 503 roentgenograms of patients with scoliosis were examined. Planimetric measurements method effectuated on roentgenograms with the help of curvometer was used in the studies. Results: Obtained results show significant divergence of measurements results of spine length effectuated in a straight line and on a curve. They depend not only on curve angle size but also on a number of vertebrae creating curvature. Conclusions: 1. Trunk length in people with scoliosis measured in a straight line is lowered, because it does not consider true spine length, in other words, arc length of a curvature. 2. Using planimetric method we can easily describe arc length and correct height dimension of a patient measured traditionally.