中文摘要：

[目的]比较不同下端固定椎的Lenkel型青少年特发性脊柱侧凸患者（adolescent idiopathic scoliosis，AIS）选择性融合术后影像学改变。[方法]选取行选择性胸椎融合术的52例Lenkel型AIS患者。按照融合下端椎将52例AIS患者分为两组：A组（下端融合椎为T12）及B组（下端融合椎为L1），进一步根据Lenke分型将Lenke1A（下端融合椎为T12／L1）及Lenke1B／1C（下端融合椎为12／L1）患者分别行矫形效果分析。[结果]术前A、B两组问各相关参数均未见统计学差异。A组患儿术后末次随访时胸腰弯／腰弯顶椎偏移、冠状面平衡、下端融合椎下位椎间盘冠状面成角及远端交界性后凸均显著大于B组患儿（P〈0．05）。根据腰弯修正型分为两组：Lenke1A及Lenke1B／C组。无论是下端融合椎为T12或L1的Lenke1A型患者术后均取得较为满意的矫形效果，冠状面及矢状面影像学改变无显著统计学差异；而Lenke1B／C（下端融合椎为L1）患者在冠状面及矢状面的矫形效果较好。[结论]在对Lenke1型患者行选择性融合术时应结合腰弯修正型制定手术策略：对于腰弯柔韧性佳的Lenke1A患者只需融合至T12即可，而Lenke1B／C患者的融合范围应延伸至L1。

英文摘要：

[ Objective ] To analyze the selection of lowest instrumented vertebra in patients with Lenke Type I adolescent idiopathic scoliosis （AIS） treated with selective thoracic fusion. [ Methods] Fifty -two girls with Lenke Type I AIS were trea ted by selective thoracic fusion. These patients were classified according to their lowest instrumented vertebra. Group A consisted of 34 patients, who underwent selective thoracic fusion to T12, and Group B consisted of 18 patients, who underwent selective thoracic fusion to L1. Patients were further divided according to the lumbar modifier A, B and C according to Lenke classifica- tion. [ Results] At latest follow -up, the lumbar apical vertebral translation, coronal balance, disk angle below LIV and DJK of Group A increased significantly versus Group B （ P 〈 0. 05） . The amount of coronal and sagittal correction in thoracic scolio sis with a lumbar modifier B and C in patients undergoing selective thoracic fusion to L1 was better than those undergoing fusion to T12. [ Conclusion] The Lenke Type I AIS patients undergoing selective thoracic fusion to T12 may develop trunk decompen sation easierly than those undergoing selective thoracic fusion to L1. If a thoracic scoliosis with a Lenke B or C lumbar curve are operated on selectively, the instrumentation should be extended into L1.