title: Fusion levels and hook patterns in thoracic scoliosis with Cotrel-Dubousset instrumentation.
abstract: This study reports the results of treatment of adolescents with King Types 2, 3, and 4 idiopathic curves using Cotrel-Dubousset instrumentation. Imbalance was seen in Types 2 and 4 curves when distraction direction hook patterns crossing the thoracolumbar junction were employed. Imbalance was not seen when a modified hook pattern employing compressing forces across the thoracolumbar junction was employed. No imbalance was observed in Type 3 curves using the basic right thoracic curve hook pattern. In Type 4 curves, a second modified hook pattern is required to obtain improved correction and balance. The mechanism of production of imbalance is explained by a three dimensional analysis of the deformity and of the forces generated by the Cotrel-Dubousset system.
authors: Miami Children's Hospital, Florida.
authors: H L
authors: HL
authors: Shufflebarger
authors: C E
authors: CE
authors: Clark
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena; D006801:Humans; D009984:Orthopedic Fixation Devices; D012600:Scoliosis / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation*; D013904:Thoracic Vertebrae / Q000601:surgery*