Surgical treatment of adolescent idiopathic scoliosis: A comparative studyof two segmental instrumentation systems

This study compares two different surgical techniques and instrumentation t ypes in the treatment of adolescent idiopathic scoliosis. The charts and ra diographs of 116 patients with adolescent idiopathic scoliosis treated by p osterior spine fusion with Isola or Cotrel-Dubousset instrumentation were r eviewed. Patients were separated into two equivalent groups matched for age , sex, curve type, and curve magnitude. All patients had a minimum of 2 yea rs follow-up. The instrumentation in group 1 consisted of hooks, wires, and pedicle screws. That used in group 2 was limited to hooks and rods. The Ma nn-Whitney, Wilcoxin, and the paired Student t tests for matched pairs were used for statistical analysis. Patients in group 1 had increased curve cor rection (66% vs. 52%), apical vertebral translation (63% vs. 30%), and corr ection of the end vertebral tilt angle (11 degrees vs. 3 degrees) (p < 0.00 1). The percentage of coronal curve correction in curves larger than 65<deg rees> also was greater in group 1 (59% vs. 40%). Physiologic sagittal align ment was obtained in 80% of the patients in group 1 and 25% in group 2. No major complication or pseudoarthrosis occurred in either group. This study supports improved correction of curve magnitude, apical translation, and en d vertebral tilt angle with the use of multiple anchor types compared with the correction achieved with standard hook-and-rod constructs.