Lumbar curve response in type ii idiopathic scoliosis after posterior instrumentation of the thoracic curve

Twentyfour patients with King Type II scoliosis ware retrospectively studied to determine if preoperative assessment of lumbar curve flexibility was predicts of pastoperalivs spinal balance. All patients had preoperative lumbar curves exceeding 40* and all underwent selective thoracic fusion with Cotrel- Dubnusset or Texas Scottish Rite Hospital instrumentation. The lumbar curves corrected 73% on preoperative band radiograph?. Despite this significant flexibility, the lumbar curves remained larger after surgery than the Instrumented thoracic curves and sp:nal imbalance oceurrfid. This finding was due., in part, to postoperative persistence of obliquity boiwean L4 and the pelvis. When using Colrel-Dubousaet or Texas Scottish Hits Hospital Instrumentation, preoperative aFsessrnert of the large lumbar curve's flexibility is not particularly helpful in predicting its response to selective thoracic fusion, especially regarding whether postoperative imbalance may occur.