三维CT观测原发性青少年脊柱侧弯患者胸椎肋横突孔的形态

Three-dimensional computerized tomography of costo-transverse foramen in adolescent idiopathic scoliosis patients

目的描述原发性青少年脊柱侧弯患者胸椎肋横突孔形态学特点，并与正常人群胸椎肋横突孔形态比较，讨论通过此空间放置内固定物治疗生长期脊柱侧弯的可行性。方法回顾性分析我院2005年7月至2013年3月于骨科行门诊或术前CT扫描三维重建的原发性青少年脊柱侧弯（右胸弯）患者（侧弯组）以及2007年5月至2012年12月行CT检查但无脊柱畸形患者（对照组）的资料。脊柱侧弯组104例，男性42例，女性62例；平均年龄10岁。Lenke分型：Ⅰ型58例、Ⅲ型46例。主胸弯Cobb角平均为45.95°。对照组38例，男性15例，女性23例，平均年龄11岁。测量脊柱侧弯患者凸侧顶椎以及上下相邻两个椎体的肋横突孔横截面积，并与正常对照组相应节段面积进行对比，总结其变化规律。结果侧弯组肋横突孔横截面积为24.67～35.57 mm2；顶椎处横截面积小于邻近上下节段面积（P〈0.05），横截面积和Cobb角呈负相关（r=-0.668, P〈0.05）。对照组肋横突孔横截面积为28.26～32.57 mm2。侧弯组肋横突孔横截面积明显大于对照组的对应节段面积（P〈0.05）。结论与正常人相比，中度原发性青少年脊柱侧弯患者侧弯凸侧胸椎肋横突孔横截面较大，可以通过此空间放置内固定器进行凸侧骨骺阻滞术。

Objective To investigate the morphology of the costo-transverse foramen in adolescent idiopathic scoliosis （AIS） patients and normal people for comparison, and to discuss the feasibility of implantation for epiphyseal growth modulation via that space in treating immature idiopathic scoliosis. Methods This is a retrospective study using three-dimensional computerized tomography （CT） to test the costo-transverse foramen in 104 AIS patients （49 males and 75 females, 10 years old in average） from July 2005 to March 2013 and 38 matched normal people （15 males and 23 females, 11 years old in average） from May 2007 to December 2012. According to the Lenke classification, there were 58 cases of Lenke Ⅰ and 46 cases of Lenke Ⅲ in the AIS group. The average Cobb angle of the main thoracic curve was 45.95 degree in the AIS group. Based on the three-dimensional reconstruction of CT data in Amira software, the cross sectional areas （CSAs） of the costo-transverse foramen in different levels were measured in both AIS and normal people. Comparisons were made within and between the AIS and normal people groups in the aspect of costo-transverse foramen CSA. Furthermore, the correlation between the CSA and the Cobb angle was also analyzed. The possible factors contributing to the foramen CSA were discussed and summarized. Results The average CSA in the AIS group ranged from 24.67 mm2 to 35.57 mm2. The CSAs in apex levels were significantly smaller than those in other levels （P〈0.05）. The CSA was negatively correlated with the magnitude of Cobb angle （r=-0.068, P〈0.05）. The average CSA of normal people group ranged from 28.26 mm2 to 32.57 mm2. The CSA of AIS group was significantly greater than that of the corresponding level in normal people group （P〈0.05）. Conclusion Comparing to the normal people, the CSA of costo-transverse foramen in AIS patient is greater, which seems to support the proposal of implant placement via this foramen in epiphyseal growth modulation.