Background. For many years the etiology of idiopathic scoliosis has been a topic of interest for researchers and clinicists. Material and methods. We examined somatosensory evoked potentials from the tibial nerves (tSSEP) in 120 children with idiopathic scoliosis, of whom 40 showed abnormal results and were retested by tSSEP one year later. The progressive nature of the scoliosis was evaluated on the basis of clinical and radiological examination. This group of 40 children was divided into two subgroups: Group I, consisting of 25 children with progressive scoliosis, and Group II, consisting of 15 children with non-progressive scoliosis. The groups were cross-referenced for one-curve scoliosis (21 children) and two-curve scoliosis (19 children). These children had been treated conservatively by asymmetrical three-plane trunk mobilization using the Dobosiewicz method. Results. Of the 40 children with abnormal results in the first tSSEP examination, 70% still had pathological recordings in the second examination. 65% of this group had progressive scoliosis, as compared to only 40.8% in the entire study population of 140 children. In the follow-up x-ray we found slight but statistically significant regressio of the Cobb angle and rotation. The radiological changes had no significant relation to changes in the tSSEPs. There was no statistically significant different in quantitative pathology on the tSSEPs between progressive and non-progressive scoliosis. Conclusions. These results may be an argument in favor of the hypothesis that idiopathic scoliosis results from a dysfunction of the sensory pathways.