The Double Rib Contour Sign (DRCS) in lateral spinal radiographs: aetiologic implications for scoliosis.

Unlabelled: All lateral spinal radiographs in idiopathic scoliosis show a DRC sign of the thoracic cage, a radiographic expression of the rib hump. The outline of the convex overlies the contour of the concave ribs. The aim of this study is to assess this DRC sign in children with and without Late Onset Idiopathic Scoliosis (LOIS) with 10 degrees -20 degrees Cobb angle, and to examine whether in scoliosis the deformity of the thorax or that of the spine develops first.