Anatomical Study on the Safety of Anterior Cervical Craniovertebral Fusion with Clival Screw Placement in Children Aged 1–6 Years

Abstract

Shao-Jie Zhang,1,2,* Kun Li,2,3,* Zhi-Jun Li,2,3 Xing Wang,2,3 Jia-Hui Dong,4 Jian Wang,2 Jie Chen,2 Xing-Yue Qu,2 Zi-Yu Li,2 Yu-Hang Liu2 1School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, People’s Republic of China; 2Department of Human Anatomy, Inner Mongolia Medical University, Hohhot, People’s Republic of China; 3Digital Medical Center, Inner Mongolia Medical University, Hohhot, People’s Republic of China; 4The First Clinical Medical College, Inner Mongolia Medical University, Hohhot, People’s Republic of China*These authors contributed equally to this workCorrespondence: Zhi-Jun LiDepartment of Human Anatomy, Inner Mongolia Medical University, Hohhot, People’s Republic of ChinaTel [phone]Email [email protected]: 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 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

Keywords

• children
• craniocervical junction region
• clivus
• internal screw fixation
• spiral computed tomography scan