腹压和子宫重量对子宫韧带影响的有限元仿真研究

The Influence of Abdominal Pressure and Uterine Weight on Uterine Ligaments by Finite Element Simulation

目的 应用有限元法分析不同子宫载荷(腹压和子宫重量)时子宫韧带的应力分布和变形情况,获得各韧带对子宫载荷变化的敏感度。方法 建立后位子宫及其附属韧带的三维模型并导入ABAQUS软件,设置载荷和约束,并计算子宫韧带的应力和变形。结果 腹压和子宫重量单独或同时变化会引起子宫韧带的拉伸变形,变形和应力随载荷的增加而增大,且主要分布于各韧带中下段或与子宫的连接处,最大应力和最大位移集中于各韧带与子宫或盆壁的连接处,并且子宫重量比腹压对各韧带的影响程度大。腹压单独或与子宫重量同时变化时,各韧带所受应力及对载荷变化的敏感度从大到小依次是骶、阔、主、圆韧带,子宫重量单独变化时排序从大到小依次是骶、主、圆、阔韧带,而各韧带变形及对载荷变化的敏感度排序保持不变,且从大到小依次是阔、圆、骶、主韧带。结论 通过有限元分析研究各子宫韧带对子宫载荷变化的敏感度,研究结果与临床资料相符,可为临床手术方案优化和发病机制探索提供指导。

Objective To analyze the influence of different loads(abdominal pressure and uterine weight) on stress and deformation of uterine ligaments using the finite element method, and obtain the sensitivity of each accessory ligament to the changes of load on uterus. Methods The three-dimensional(3D) models of retroverted uterus and its accessory ligaments were established, loads and constraints were set in ABAQUS software, and the stress and deformation of uterine ligaments were calculated. Results The changes of abdominal pressure and uterine weight alone or both together would cause tensile deformation of uterine ligaments, and the deformation and stress increased with the load increasing. The deformation and stress were mainly distributed in the middle and lower part of each ligament or at the junction with uterus. The maximum stress and displacement were concentrated at the junction of each ligament with uterus or pelvic wall, and uterus weight had a greater influence on the ligaments than abdominal pressure. When abdominal pressure changed alone or together with uterine weight, the stress and sensitivity to load changes of the ligaments were in the order of uterosacral ligament(USL), broad ligament(BL), cardinal ligament(CL) and round ligament(RL). When uterine weight changed alone, the stress and sensitivity to load changes of the ligaments were in the order of USL>CL>RL>BL. The deformation and sensitivity to load changes of the ligaments remained unchanged and the order was BL>RL>USL>CL. Conclusions The sensitivity of each uterine ligament changing with uterine load was studied through finite element analysis, and the research results were consistent with the clinical data, which could provide guidance for optimization of surgical scheme of uterus prolapsed in clinic and exploration of pathogenesis.