Objective: To verify the relation of muscular response to the vestibular stimulation of the erector spinae, specifically longissimus thoracis and iliocostalis lumborum, with the origin of scoliosis in a population of individuals with level V cerebral palsy of the Gross Motor Function Classification System (GMFCS). Methods: Cross-sectional study of 12 individuals aged between four and 14 years. The muscular activity of the longissimus thoracis and iliocostalis lumborum was recorded by electromyography in the presence of anteroposterior and lateral imbalances, comparing it with that obtained in sitting position without imbalances. Scoliosis was assessed by radiological study following Cobb method. Results: Statistically significant differences were found between correct responses of both muscles to anteroposterior imbalances and absence of right thoracolumbar scoliosis (p=0.005; p=0.028), left thoracic scoliosis (p=0.005; p=0.046) and right lumbar scoliosis (p=0.005; p=0.046). Conclusions: The symmetry of muscular responses to anteroposterior imbalances, both of longissimus thoracis and iliocostalis lumborum, seems to be one of the factors that prevent the development of spine deviations in this population. Level of evidence: IV. Type of Study: Case series