Preoperative supine traction radiographs often result in higher Lenke classifications than supine bending radiographs in adolescent idiopathic scoliosis.

Study Design: Retrospective chart and radiographic review.

Objective: The purpose of this study is to determine if both traction and side-bending radiographs yield the same Lenke classification. Supine side-bending radiographs are used to evaluate curve flexibility and assign Lenke classification in Adolescent Idiopathic Scoliosis (AIS).