Objective: This study aimed to investigate the safety of clival screw placement in children aged 1– 6 years.
Methods: The cranial computed tomography data of 92 children aged 1– 6 years were divided into three groups, according to age, for three-dimensional reconstruction. Three clival screw placement points were defined: (1) median point A at the middle and upper third of the tripartite distance from the spheno-occipital synchondrosis to the base of the skull; (2, 3) critical points B and C on the horizontal line with point A, where the screw placement passage was parallel to the sagittal plane. Parameters such as the passage length and angle were measured for horizontal, vertical facial, and extreme screw placement.
Results: The length parameters of the clival screw placement increased with age, and the screw passage length was the shortest for the vertical facial type in each age group. There were significant differences in all three groups between the length of screw placement in the vertical bone surface, the length of screw placement in the horizontal direction, and the length of screw placement on the limit at points A, B, and C (P < 0.05); the length of screw placement on the vertical bone surface was the shortest. There was no significant difference between the horizontal screw length at point A and the extreme screw length (P > 0.05). The difference between the horizontal screw length and the extreme screw length in the groups aged 1– 2 years and 5– 6 years was statistically significant (P < 0.05), and the horizontal screw length was longer.
Conclusion: The cranial slope of children aged 1– 6 years has the morphological basis for the placement of 3.5 mm screws, and each placement point has a safe angle range for screw placement.

Keywords: children, craniocervical junction region, clivus, internal screw fixation, spiral computed tomography scan


中文翻译：

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1～6岁儿童颈椎前路颅椎融合斜坡螺钉置入安全性的解剖学研究

目的：本研究旨在调查 1-6 岁儿童放置斜坡螺钉的安全性。
方法：将92名1～6岁儿童的头颅CT资料按年龄分为三组进行三维重建。定义了三个斜坡螺钉放置点：（1）中点A，在蝶枕联合软骨到颅底三方距离的中上三分之一处；(2, 3) 临界点 B 和 C 在与点 A 的水平线上，螺钉放置通道与矢状面平行。测量水平、垂直面部和极端螺钉放置的通道长度和角度等参数。
结果：斜坡螺钉置入长度参数随年龄增长而增加，各年龄组中垂直面型螺钉通道长度最短。三组在垂直骨面置钉长度、水平方向置钉长度、A、B、C点限位螺钉置钉长度方面差异均有统计学意义（P < 0.05); 垂直骨面置钉长度最短。A点水平螺钉长度与极端螺钉长度无显着差异（P >0.05）。1～2岁组和5～6岁组水平螺钉长度和极限螺钉长度的差异有统计学意义（P < 0.05)，水平螺钉长度较长。
结论： 1～6岁儿童颅骨斜面具有置入3.5 mm螺钉的形态学基础，且每个置入点均有螺钉置入的安全角度范围。

Keywords:儿童, 颅颈交界区, 斜坡, 内螺钉固定, 螺旋CT扫描