Shao Long, Wu Xiangdong, Fang Chaohua, Zhu Hongli, Tao Kun, Wang Shicheng
Joint and Sports Medicine Center, Ningbo No.6 Hospital, 1059 Zhongshan East Road, Ningbo, 315040, Zhejiang, China.
Department of Orthopaedic Surgery, Beijing Jishuitan Hospital, Capital Medical University, Fourth Clinical College of Peking University, National Center for Orthopaedics, Beijing, 100035, China.
Eur J Med Res. 2025 Jun 12;30(1):476. doi: 10.1186/s40001-025-02747-5.
This study aims to clarify the combined influence of the tibial rotational alignment and posterior slope on knee joint biomechanics after posterior-stabilized total knee arthroplasty using a computer simulation.
Computer tomographic and magnetic resonance imaging scan of a healthy volunteer were used to reconstruct a detailed 3D geometrical model. A virtual surgery was performed to generate a resection plane with different posterior slopes and rotational alignment on the proximal tibia. The internal, neutral and external rotation, combined with a posterior slope of 0, 3, 5, and 7 degrees were simulated for both standing and bending position. The differences in contact pressure, area and stress of polyethene liner and the tensile stress of the soft tissue were compared.
The contact area on the polyethylene liner decreased with increasing posterior slope in a standing position while the opposite trend was found in a bending position. In a bending position, internal rotation of tibial component resulted in smaller contact areas than neutral or external rotation. A posterior slope of 0° combined with neutral rotation in a standing position showed the smallest pressure on the liner with biggest contact area. The distribution of von Mises stress was more uniform with 0° and 3° than 5° and 7° posterior tibial slope for both standing and bending position. The stress increased with increasing posterior slope in both standing and bending position, ranging from 8.77 MPa to 79.39 MPa. The ligament and muscle tensile stress increased with increasing posterior slope in both standing and bending position. In addition, the neutral rotation showed lower maximum stress compared with other rotational alignment in a standing position.
An increased posterior slope increases the contact pressure and stress of the polyethene liner and the ligament tensile stress. A neutral rotation combined with a posterior slope of less than 3° showed superior biomechanical results in posterior-stabilized TKA.
本研究旨在通过计算机模拟阐明后稳定型全膝关节置换术后胫骨旋转对线和后倾角度对膝关节生物力学的联合影响。
使用健康志愿者的计算机断层扫描和磁共振成像扫描重建详细的三维几何模型。进行虚拟手术，在胫骨近端生成具有不同后倾角度和旋转对线的截骨平面。模拟站立位和屈膝位时，内旋、中立位和外旋，以及后倾角度为0°、3°、5°和7°的情况。比较聚乙烯衬垫的接触压力、面积和应力以及软组织的拉伸应力差异。
站立位时，聚乙烯衬垫上的接触面积随后倾角度增加而减小，而屈膝位时则呈现相反趋势。屈膝位时，胫骨假体组件内旋导致的接触面积小于中立位或外旋。站立位时，后倾角度为0°并结合中立位旋转时，衬垫上的压力最小，接触面积最大。对于站立位和屈膝位，后倾角度为0°和3°时的冯·米塞斯应力分布比5°和7°时更均匀。站立位和屈膝位时，应力均随后倾角度增加而增加，范围为8.77兆帕至79.39兆帕。站立位和屈膝位时，韧带和肌肉的拉伸应力均随后倾角度增加而增加。此外，站立位时，中立位旋转的最大应力低于其他旋转对线。
后倾角度增加会增加聚乙烯衬垫的接触压力和应力以及韧带拉伸应力。后稳定型全膝关节置换术中，后倾角度小于3°并结合中立位旋转显示出更好的生物力学结果。
