43 girls (aged 10-16) with adolescent idiopathic scoliosis were randomized to be prescribed either a SpineCor dynamic flexible spinal brace or a conventional rigid spinal brace. The purpose of this study was to evaluate the efficacy of a nonrigid brace for preventing curve progression relative to the current bracing standard. Patients were prescribed to wear allocated braces for 23h daily until weaning upon skeletal maturity. Up to stoppage of brace wear, the nonrigid group demonstrated a significantly greater rate of patients with curve progression above 5 degrees Cobb angle from baseline. After brace wear had stopped, the groups demonstrated similar rates of patients with curve progression above 5dg in Cobb angle.