Adolescent idiopathic scoliosis (AIS) is defined by lateral curvature of the spine with Cobb angle greater tan 10 degrees, age of onset older than 10 years, and no underlying etiology. The evaluation of this patology focuses on looking for an underlying etiology, evaluating the magnitude of the curve, and determining the risk of progression. In this article we present a case of rapidly evolving scoliosis that makes us question when MRI is indicated.