柱形金属补块修复膝关节翻修胫骨缺损的有限元分析△（开放获取）

Finite element analysis of pillar metal augment for repairing tibial bone defect in revision knee arthroplasty（OA）

摘要:

[目的]探讨柱形金属补块应用于膝关节翻修胫骨缺损，对胫骨平台假体稳定性和胫骨平台骨应力的影响。[方法] 利用人工胫骨模型建立三维计算模型，制作胫骨内侧平台骨缺损并模拟膝关节翻修手术。在传统手术模型中，使用骨水泥修复骨缺损；而在柱形金属补块手术模型中，使用柱形金属补块修复骨缺损。两种手术模型中均使用延长杆和锥形金属补块。给模型加载负荷，测量和比较两种手术模型的胫骨内侧平台骨-骨水泥界面微动和骨 von Mises 应力。[结果]传统手术模型和柱形金属补块手术模型中胫骨内侧平台松质骨-骨水泥界面微动的差异无统计学意义 [(1.1±0.3) μm vs (1.0±0.4) μm, P=0.365]，但是，传统手术模型的胫骨内侧平台皮质骨-骨水泥界面微动显著大于柱形金属补块手术模型 [(2.7±1.2) μm vs (2.6±1.2) μm, P=0.032]。此外， 传统手术模型的胫骨内侧平台松质骨 von Mises 应力显著小于柱形金属补块手术模型 [(0.2±0.0) MPa vs (0.7±0.1) MPa, P＜0.001]，尽管两个模型胫骨内侧平台皮质骨 von Mises 应力的差异无统计学意义 [(4.0±1.3) MPa vs (3.9±1.3) MPa, P=0.071]。[结论] 柱形金属补块修复膝关节翻修胫骨缺损，可以增加假体稳定性和胫骨平台骨应力。

Abstract:

[Objective] To investigate the effect of pillar metal augment used for tibial bone defect in revision knee arthroplasty on the stability of the tibial implant and the bony stress on the tibial plateau. [Methods] Bone defect was created in the medial tibial plateau of a 3D computational model from a composite tibia model, and revision knee arthroplasty was simulated. Cement was used for repairing the tibial bone defect in the traditional revision model (TRM), while pillar metal augment was used for repairing tibial bone defect in the pillar metal augment revision model (PMA). Stem and cone metal augment were used in both revision models. As load was applied to the models, the micromotion at the bone-cement interface and the von Mises stress on the bone of the medial tibial plateau were measured and compared between these two models. [Results] Although there was no significant difference in the micromotion of the cancellous bone-cement interface of the medial tibial plateau between the TRM and PMA [(1.1±0.3) μm vs (1.0±0.4) μm, P=0.365], the TRM proved significantly greater than the PMA in term of the cortical bone-cement interface of the medial tibial plateau [(2.7±1.2) μm vs (2.6±1.2) μm, P=0.032]. In addition, the TRM had significantly lower von Mises stress on cancellous bone of the medial tibial plateau than the PMA [(0.2±0.0) MPa vs (0.7±0.1) MPa, P＜0.001], whereas there was no significant difference in von Mises stress on the cortical bone of the tibial plateau between the TRM and the PMA [(4.0±1.3) MPa vs (3.9±1.3) MPa, P=0.071]. [Conclusion] The pillar metal augment used for tibial bone defect in revision knee arthroplasty does improve the stability of the prosthetic component, and increase the stress on cancellous bone of the tibial plateau.