Background and Objective. A common reconstruction procedure after a wide resection of bone tumors around the knee is endoprosthetic knee replacement. The aim of this study was to investigate the characteristics of bone injury of the patient after endoprosthetic knee replacement during walking. Methods. A subject-specific finite element model of the femur-prosthesis-tibia complex was established via CT scans. To obtain its physiologically realistic loading environments, the musculoskeletal inverse dynamic analysis was implemented. The extracted muscle forces and ground forces were then applied to the finite element model to investigate bone stress distribution at various stages of the gait cycle. Results. The maximum femur stress of each stage varied from 33.14 MPa to 70.61 MPa in the gait cycle. The stress concentration position with a distance of 267.2 mm to the tibial plateau showed a good agreement with the patient injury data. Conclusions. Overall results indicated the reasonability of the simulation method to determine loading environments and injury characteristics which the patient experienced with knee endoprosthesis during walking.

中文翻译：

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人工膝关节置换术后股骨皮质骨衰竭的耦合肌肉骨骼动力学和特定对象有限元分析。

背景和目的。膝关节周围骨肿瘤大范围切除后的常见重建手术是人工膝关节置换术。本研究的目的是调查患者在步行过程中进行人工膝关节置换术后骨损伤的特征。方法。通过 CT 扫描建立了股骨-假体-胫骨复合体的特定对象有限元模型。为了获得生理上真实的负载环境，实施了肌肉骨骼逆动力学分析。然后将提取的肌肉力和地面力应用于有限元模型，以研究步态周期各个阶段的骨应力分布。结果. 在步态周期中，每个阶段的最大股骨应力从 33.14 MPa 到 70.61 MPa 不等。距胫骨平台267.2 mm的应力集中位置与患者损伤数据吻合较好。结论。总体结果表明，该模拟方法在确定患者在行走过程中使用膝关节假体时所经历的负荷环境和损伤特征是合理的。