ADOLESCENT IDIOPATHIC SCOLIOSIS: EVALUATION ON THE EFFECT OF SCREW DENSITY IN THE CORRECTION

ABSTRACT Objective: The objective was to investigate implant density or the number of screws correlated with the correction of the main curve in patients undergoing surgery for adolescent idiopathic scoliosis (AIS). Methods: We evaluated 112 medical records: 33 patients with screw density of up to 50%, and 79 patients with a density of 100%; all patients underwent surgical correction by posterior approach with transpedicular fixation. Results: In the group of patients with screw density of up to 50% the residual Cobb median was 10°; in the group with 100% density, the median was 7°. Conclusion: Biostatistical analysis showed that the group with up to 50% of screw density presented correction rate of 82.1% and the group with 100% density had correction of about 86.8%. It is therefore concluded that the difference is statistically significant in favor of the fixation with 100% density (p =0.010).摘要 目的：本研究旨在探讨青少年特发性脊柱侧凸（adolescent idiopathic scoliosis, AIS）患者行手术治疗时，内固定螺钉密度（即螺钉植入数量）与主弯矫正效果的相关性。 方法：本研究纳入112份临床病历资料进行分析：其中螺钉密度≤50%的患者共33例，螺钉密度为100%的患者共79例；所有患者均接受后路经椎弓根固定矫形手术。 结果：螺钉密度≤50%组的残余Cobb角中位数为10°；螺钉密度100%组的残余Cobb角中位数为7°。 结论：生物统计学分析结果显示，螺钉密度≤50%组的脊柱侧凸矫正率为82.1%，螺钉密度100%组的矫正率约为86.8%。据此可得出结论：100%螺钉密度固定方案的矫形效果具有统计学显著性优势（p=0.010）。