有限元法分析0-6岁儿童枕寰枢复合体发育及其生物力学的变化特征

Development and biomechanical properties of occipital atlantoaxial complex in 0-6-year-old children: a finite element analysis

背景:0-6岁儿童各类严重创伤、畸形、肿瘤、结核、炎症等均极易导致枕寰枢复合体区损伤。当出现损伤压迫延髓、上颈髓、诸多神经血管等危重情况时需手术矫治以恢复该区力学稳定,但鉴于该期儿童有不同于青少年和成人的发育特征,国内外学者对其前、后或侧路手术内固定器械方案设计、矫形固定和力学机制等至今仍无深入研究和统一认识。目的:通过分析0-6岁儿童枕寰枢复合体区形态特征基础数据综述其形态发育规律和力学机制,将填充国人儿童该区发育形态学、影像学和微结构力学数据库,并为发育性、外伤性该区疾病的预防、诊治及内固定术器械设计、研发等提供理论依据。方法:用计算机检索2004年1月至2017年12月PubMed数据库、中国知网及万方数据库的相关文章,英文检索词"0-6 years old,pediatric,occipital atlantoaxial complex,anatomy,biomechanical";中文检索词"0-6岁小儿,枕寰枢复合体,解剖,生物力学",共检索到82篇相关文献,58篇文献符合纳入标准。结果与结论:(1)0-6岁儿童寰枢椎及颅底复杂解剖结构更加细小且变异大、毗邻关系复杂,无法以成人或青少年螺钉内技术相关数据简单地应用于"非成人等比例缩小"的发育中幼儿,加之手术风险极高,故提高置钉的准确性和降低失误率已成为曾经"生命禁区"内固定能否普遍基层开展的关键所在;(2)0-6岁小儿枕寰枢复合体区严重损伤应内固定治疗,后路内固定是常用术式,因常合并多种畸形,各患儿的骨质结构差异大,内固定置钉更为困难。

BACKGROUND： All types of severe trauma, malformations, tumors, tuberculosis, and inflammation in 0-6 years old children can easily cause damage to the occipital atlantoaxial complex. When the injury compresses the medulla oblongata, the upper cervical cord, nerves, and blood vessels, surgical correction is needed to restore the mechanical stability of the area. Given that this period of children have different development characteristics from adolescents and adults, the design of internal fixators through anterior, posterior or lateral approaches, orthopedic fixation and mechanical mechanism have not been studied in-depth and unified at home and abroad. OBJECTIVE： To analyze the morphological development and mechanical mechanism of occipital atlantoaxial complex morphological characteristics in children aged 0-6 years, and to enrich the database of developmental morphological, imaging, and microstructural mechanics of Chinese, and to provide reference for prevention, diagnosis of the disease and treatment and internal fixation device design, research and development. METHODS： A computer-based retrieval of PubMed, CNKI and Wan Fang databases was performed for the articles published between January 2004 and December 2017. The keywords were ＂0-6 years old, pediatric, occipital atlantoaxial complex, anatomy, biomechanical＂ in English and Chinese, respectively. Eighty-two articles were retrieved, and 58 articles were eligible for the inclusion criteria. RESULTS AND CONCLUSION：（1） The complex anatomy of the vertebral and skull bases in Children aged 0-6 years is more subtle and highly variable, and the adjacent relationship is complex. Therefore, the adult or juvenile screw-related technical data cannot be applied in developing children, and the surgical risk is very high. Thus, improving the accuracy of nail placement and reducing the error rate have become the key for whether internal fixation can be widely utilized in the occipital atlantoaxial complex surgeries.（2） The severe injury of occipital atlantoaxial complex in 0-6 years old children should be treated with internal fixation, and posterior internal fixation is a commonly used method. Because accompanied with a variety of deformities, and the bone structure is different among children, internal fixation becomes very difficult.