中文摘要：

目的：探讨顶椎置钉与否对Lenke1型青少年特发性脊柱侧凸（AIS）患者矫形效果的影响°方法：回顾性分析从2009年6月～2010年1月采用全椎弓根螺钉后路矫形内固定融合术治疗的69例Lenke1型AIS患者，年龄12—20岁，平均15．0岁，主弯Cobb角50°-70°，平均53．7°,根据顶椎置钉与否分为：顶椎凸凹侧均未置人螺钉组（A组，35例）和至少一侧置入螺钉固定组（B组，34例）。记录两组患者术前年龄、性别、主弯Cobb角、柔韧度、顶椎旋转度和固定节段数、置入物密度、术后Cobb角、主弯Cobb角矫正率、顶椎去旋转率等指标并进行两组间的比较分析。B组病例在CT图像上统计顶椎不良置钉率。结果：两组患者年龄、性别比、术前主弯Cobb角、柔韧度和顶椎旋转度等资料均无统计学差异（P〉0．05）。所有病例矫形术后均未发生冠状面与矢状面的失代偿。随访24～30个月，平均27．7个月，两组患者无内固定松动及断钉断棒，植骨融合牢固，均未出现明显的矫正丢失。A、B两组置人物密度分别为63．4％、65．3％，平均固定节段数分别为11-3和11．6，主弯Cobb角矫正率分别为73．9％和72．6％。两组在置人物密度、内固定节段数和主弯Cobb角矫正率方面均无统计学差异（P〉0．05）。术后顶椎去旋转率A组为18．4％，显著低于B组的34．8％（P〈0．05）。B组顶椎置入的41枚螺钉中，有5枚为不良置钉（12．2％）°结论：对于Cobb角在50°-70°非严重的Lenke1型青少年特发性脊柱侧凸，顶椎置钉尽管并不能显著提高侧凸矫正率，但可以明显矫正顶椎旋转，因此，在注意置钉安全性的前提下，应尽量在顶椎置人椎弓根螺钉。

英文摘要：

Objectives： To investigate the effect of apical pedicle screw instrumentation on the correction of thoracic adolescent idiopathic scoliosis（AIS）. Methods： From June 2009 to January 2010, 69 Lenke 1 type AIS patients treated with exclusive pedicle screw instrumentation were reviewed. The mean age at the time of surgery was 15.0 years old（range, 12-20 years）, and the Cobb angle was 53.7° on average（range, 50°-70°）. According to whether pedicle screws were inserted in the apical vertebrae, all cases were divided into two groups： group A（without apical instrumentation, 35 cases） and group B（instrumented with screws, 34 cases）. The preoperative chronological age, sex, the Cobb angle of the major curve, and rotation degree of the apex were compared between two groups. The implant density, postoperative Cobb angle, the correction rate in Cobb angle, and derotation degree of the apical vertebra were also recorded and compared between two groups. While in group B, misplacement of the apical screws was calculated on CT scans. Results： There was no statistical difference with respect to the chronological age, gender distribution, the preoperative Cobb angle, curve flexibility and rotation degree of the apex between the two groups. No case suffered from coronal or sagittal imbalance postoperatively. The loss of correction was also not significant in both groups. The implant density averaged 63.4% in group A and 65.3% in group B. The fusion levels were 1t.3 in group A and 11.6 in group B. The correction rate in Cobb angle was 73.9% in group A and 72.6% in group B. There was no statistical difference in terms of implant density, number of fused vertebrae or the Cobb angle correction rate between the two groups. However, as for the demtation degree of the apical vertebrae, group A had a signifi- cantly lower degree（18.4%） than group B（34.8%）（P〈0.05）. In the 41 pedicle screws instrumented in the apical vertebrae in group B, 5（12.2%） were identified as misplacement. Conclusions：