经骶1置入骶髂关节螺钉固定时骶骨“非安全区”的解剖学研究

Anatomic study of the non-secure area of sacrum by first sacral verterbra screw fixation for the sacroiliac joint

目的：通过观测骶骨侧位前上方“非安全区”的解剖学数据,为经骶1（S1）置入骶髂关节螺钉提供解剖学依据。方法选用河北医科大学解剖学教研室提供的18具正常成人骶骨防腐标本。行骶骨“非安全区”测量：应用游标卡尺及直尺测量S1椎体中线前后径长度（ D）、测量骶骨翼斜坡在S1椎体投影的长度（ L）；圆规找到S1椎体前缘在椎体与骶骨翼移形侧面的投影点,游标卡尺测量两点间距离（ H）。以L为底,H为高,通过三角形面积公式计算S1椎体“非安全区”面积,并比较不同性别间的S1椎体“非安全区”面积。结果去除观测中变异较大的4具标本,余14具中,男（7例）、女（7例） S1椎体 D 分别为（27.68±0.90） mm 和（26.30±2.38） mm,L 分别为（23.62±2.62） mm、（22.05±1.25）mm,H分别为（17.70±0.98） mm、（16.40±1.03）mm。骶骨“非安全区”的面积分别为（209.10±30.99）mm2、（180.79±15.21） mm2,男、女骶骨“非安全区”面积差异无统计学意义（t=-2.170, P〉0.05）,且面积较恒定。结论 S1椎体侧位前上方存在骶髂关节螺钉置入的“非安全区”,且面积较恒定。避开“非安全区”置入骶髂关节螺钉可有效减少螺钉误置的危险。

Objective To provide anatomic basis for iliosacral screw fixation at the level of the first sacral vertebra （ S1 ） by the study of non-secure area. Methods Eighteen adult sacrum corrosion specimens, provided by Hebei Medcal University were studied. The midline diameter length of the S1 vertebral（D）, length of sacral slope and in projection of the vertebral of the S1（L）, height from anterior body of the S1 to the sacral slope in projection of the vertebral of the S1 （ H） were measured. The area of the＂non-secure area＂ by formula of triangle area was caculated and the area in male and female was compared. Results The specimens with large variation were excluded. The D in male and female were （27. 68 ± 0. 90）mm and （26. 30 ± 2. 38） mm, respectively. The L in male and female were （23. 62 ± 2. 62） mm and （22. 05 ± 1. 25） mm, respectively. The H in male and female were （17. 70 ± 0. 98） mm and （16. 40 ± 1. 03）mm, respectively. The ＂non-secure area＂ was calculated by formula of triangle area. The area in male and female were （209. 10 ± 30. 99） mm2 and（180. 79 ± 15. 21） mm2, respectively. There was no significant difference between both male and female in non-secure area （t= -2. 170, P〉0. 05）. The area of it was relatively constant. Conclusions There is non-secure area for implanting S1-screw in anterosuperior of S1 vertebral, and the area is relatively constant. It can effectively prevent screws penetration the sacrum by avoiding implantation of sacroiliac joint to non-secure area.