Liu Yang, Chen Bingpeng, Wang Chenyu, Chen Hao, Zhang Aobo, Yin Weihuang, Wu Naichao, Han Qing, Wang Jincheng
Department of Orthopedics, The Second Hospital of Jilin University, Changchun, China.
Department of Plastic and Reconstructive Surgery, First Bethune Hospital of Jilin University, Changchun, China.
Front Bioeng Biotechnol. 2021 Nov 8;9:765438. doi: 10.3389/fbioe.2021.765438. eCollection 2021.
Metal block augmentation, which is used for the treatment of tibial bone defects in total knee arthroplasty, with high stiffness will cause significant alteration in stress distribution, and its solid structure is not suitable for osseointegration. This study aimed to design a porous block to reduce weight, promote bone ingrowth, and improve its biomechanical performance. The metal block augmentation technique was applied to finite element models of tibial bone defects. Minimum compliance topology optimization subject to volume fraction combined with the porous architecture was adopted to redesign the block. Biomechanical changes compared with the original block were analyzed by finite element analysis. The stress distribution of the block and proximal tibia was recorded. The strain energy density of the proximal tibia was obtained. The newly designed block realized 40% weight reduction. The maximum stress in the optimized block decreased by 11.6% when compared with the solid one. The maximum stress of the proximal tibia in the optimized group increased by 18.6%. The stress of the anterior, medial, and posterior parts of the proximal medial tibia in the optimized group was significantly greater than that in the original group (all < 0.05). The optimized block could effectively improve the biomechanical performance between the block and the bone. The presented method might provide a reference for the design of customized three-dimensional printed prostheses.
金属块增强术用于全膝关节置换术中胫骨骨缺损的治疗，其高刚度会导致应力分布发生显著改变，并且其实体结构不适合骨整合。本研究旨在设计一种多孔块以减轻重量、促进骨长入并改善其生物力学性能。将金属块增强技术应用于胫骨骨缺损的有限元模型。采用基于体积分数的最小柔顺拓扑优化结合多孔结构来重新设计该块体。通过有限元分析比较重新设计的块体与原始块体的生物力学变化。记录块体和胫骨近端的应力分布。获得胫骨近端的应变能密度。新设计的块体重量减轻了40%。与实体块体相比，优化后的块体最大应力降低了11.6%。优化组胫骨近端的最大应力增加了18.6%。优化组胫骨近端内侧前部、内侧和后部的应力明显大于原始组（均P<0.05）。优化后的块体能有效改善块体与骨之间的生物力学性能。所提出的方法可能为定制三维打印假体的设计提供参考。
