Differences in the Risser grading systems in the United States and France.

Unlabelled: A grading system for ossification of the iliac apophysis (Risser sign) came into use in the mid 1950s in the United States and was adopted sometime later with modifications in France and other European countries. Although called by the same name, these systems have important differences that could lead to different choices of how and when to treat patients with spinal deformity. In a retrospective study, two experienced examiners (FDB and KPV) independently reviewed 301 randomly selected spine radiographs from 167 patients with adolescent idiopathic scoliosis and graded them for bilateral iliac crest apophyseal excursion each using a different system.