腰5椎弓根分型及螺钉固定的相关解剖学测量

An anatomic study of L5 pedicle classification and associated pedicle screw instrumentation

中文关键词:  第5腰椎  解剖  椎弓根螺钉  分类  测量

英文关键词:L5 vertebrae  Anatomy  Pedicle screw  Classification  Measurement

中文摘要:

  【摘要】 目的：研究腰5（L5）椎弓根的解剖特点，探讨更适合于中国人的L5椎弓根螺钉个性化置钉方法。方法：收集46个中国成人L5脊椎干燥完整标本，观察其椎弓根形态，测量与椎弓根螺钉置钉有关的椎弓根解剖参数，即在椎弓根峡部垂直于椎弓根轴切断椎弓根，在其横断面上测量椎弓根的高度、宽度与椎弓根最长径、最短径及椎弓根冠状面倾斜角；测量进钉点与人字嵴及峡部嵴在内外方向的距离；在经椎弓根轴线的L5横切面上测量置钉的理想外偏角度及范围。结果：L5椎弓根有2种形态，一种横突融合于椎弓根与椎弓连接处，谓之L型，共36个脊椎72个椎弓根；另一种是S型，共10个脊椎20个椎弓根，其横突于椎体侧后方与椎体及椎弓根融合。L型和S型椎弓根峡部横断面宽度、高度与椎弓根最长径、最短径及椎弓根冠状面倾斜角分别为18.22mm和22.45mm、14.24mm和14.46mm、20.62mm和23.74mm、11.87mm和12.83mm、35.9°和32.3°。在内外方向上进钉点到人字嵴、峡部嵴的距离L型分别为3.36mm和5.94mm，S型分别为4.66mm和7.54mm。理想的置钉外偏角L型为25.4°，S型为27.9°。除椎弓根高度外，其他各项参数两型之间的差异均有统计学意义（P＜0.05）。结论：中国人L5椎弓根可分为两种类型，S型椎弓根比L型更宽，最佳进钉点到人字嵴及峡部嵴的距离更靠外，横切面上的置钉外偏角更大。

英文摘要:

  【Abstract】 Objective：To investigate the anatomic characteristics of L5 pedicle and the optimal individualized pedicle screw placement in Chinese.Method：46 dry and intact L5 vertebrae specimens harvested from Chinese were obtained.The pedicle morphology was observed，and the anatomic parameters of the pedicle associated with pedicle screw placement were measured.Namely the pedicle isthmus were dissected along transverse section of perpendicular to the pedicle axial.Pedicle isthmus width，height，maximum diameter，minimum diameter，coronal pedicle tilt angles in the transverse section of perpendicular to pedicle axis and appropriate insertion angles in the L5 cross-section through pedicle axis were measured.In addition，the medial-lateral distance from the optimal starting point to vertex of "∧"-shaped crest and isthmic crest were measured.Result：2 morphological findings were evidenced in L5 pedicles.36 vertebrae（72 pedicles） had transverse process integrated into the junction of vertebral arch and pedicle（L-type），and 10 vertebrae（20 pedicles） had transverse process integrated into vertebral body and pedicle at the posterolateral side of the vertebral body（S-type）.The pedicle width，height，maximum diameter，minimum diameter，pedicle tilt angles was 18.22mm and 22.45mm，14.24mm and 14.46mm，20.62mm and 23.74mm，11.87mm and 12.83mm，35.9° and 32.3° for L and S type respectively.In the medial-lateral direction，the entrance point is 3.36mm and 5.94mm，4.66mm and 7.54mm lateral to vertex of "∧"-shaped crest and the isthmic crest for L type and S type pedicle，respectively.The Optimal insertion angles was 25.4° and 27.9° for L and S type respectively.Conclusion：L5 pedicle has 2 differentiation types in the Chinese.Compared with L-type，S-type pedicle has longer diameter and more lateral entrance point to the vertex of "∧"-shaped crest andisthmic crest，which optimize larger extroversion angle.