Curve Overcorrection Predicts Coronal Imbalance in Selective Thoracic Fusion in Adolescent Idiopathic Scoliosis.

A decreased preoperative flexibility and a higher FBCI was significantly associated with coronal imbalance. A high FBCI is an indication of a curve correction that exceeds the inherent flexibility of the spine, and our results add to a growing body of evidence that "overcorrection" of the main curve can lead to postoperative imbalance.