三维有限元生物力学分析后交叉韧带断裂后膝关节内翻及外旋时的应力

摘要

BACKGROUND:The incidence of posterior cruciate ligament injury combined with other knee ligament injuries is relatively high, but studies on the internal dynamic stress change of these ligaments are stil rare. OBJECTIVE:To simulate three-dimensional finite element model of the normal human knee and the complete posterior cruciate ligament rupture (III injury), calculate and analyze the stress distribution and changes of the medial collateral ligament, the lateral collateral ligament and the anterior cruciate ligament in the normal knee model and the complete posterior cruciate ligament rupture model. METHODS:We collected CT and MRI images of the healthy male right knee, and established three-dimensional finite element model of the normal human knee by using E-feature Biomedical Modeler, and ANSYS software. The simulation of a flexion moment at 0°, 30°, 60°, varus/valgus and internal/external rotation torque was applied on the established three-dimensional finite element model of the normal knee. The stress of posterior cruciate ligament, lateral collateral ligament, anterior cruciate ligament and medial col ateral ligament was analyzed. During simulation of complete posterior cruciate ligament rupture, the stress of lateral coll ateral ligament, anterior cruciate ligament and medial col ateral ligament was analyzed. RESULTS AND CONCLUSION:Three-dimensional finite element biomechanical analysis data revealed that after posterior cruciate ligament rupture, the stress of lateral coll ateral ligament during inversion and external rotation of the knee joint obviously increased, but the stress of anterior cruciate ligament and medial collateral ligament slightly altered. These findings suggested that posterior cruciate ligament rupture may cause secondary injury to other ligaments of the knee joint, and further support the importance of the dynamic stability of the knee joint.%背景:后交叉韧带损伤合并膝关节周围其他韧带损伤的发生率相对较高,然而这些韧带之间内在动态应力变化情况的报道目前尚属罕见.目的:模拟正常及后交叉韧带完全断裂(Ⅲ度损伤)的膝关节三维有限元模型,计算并分析正常膝关节模型和后交叉韧带完全断裂模型中内侧副韧带、外侧副韧带和前交叉韧带的应力分布及变化情况.方法:采集正常志愿者右膝关节的CT及MRI图像,利用E-feature Biomedical Modeler,ANSYS等软件建立正常膝关节三维有限元模型,模拟正常膝关节屈曲0°、30°、60°时施加内外翻及内外旋力矩,分析后交叉韧带、外侧副韧带、前交叉韧带及内侧副韧带的应力,模拟后交叉韧带完全断裂时分析外侧副韧带、前交叉韧带和内侧副韧带的应力.结果与结论:三维有限元生物力学分析数据显示后交叉韧带断裂后外侧副韧带在膝关节内翻及外旋运动时应力明显增大,前交叉韧带及内侧副韧带的应力变化较小.提示后交叉韧带断裂可能造成膝关节其他韧带的继发损伤,进一步支持了恢复膝关节动态稳定的重要性.