Samsami Shabnam, Herrmann Sven, Pätzold Robert, Winkler Martin, Augat Peter
Laboratory of Biomechanics and Experimental Orthopaedics, Department of Orthopedic Surgery, Physical Medicine and Rehabilitation, University Hospital of Munich (LMU), Fraunhoferstraße 20, 82152 Planegg, Munich, Germany; Institute for Biomechanics, Berufsgenossenschaftliche Unfallklinik Murnau, Professor-Küntscher-Straße 8, 82418 Murnau, Germany.
Institute for Biomechanics, Berufsgenossenschaftliche Unfallklinik Murnau, Professor-Küntscher-Straße 8, 82418 Murnau, Germany; Institute for Biomechanics, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg, Austria.
Med Eng Phys. 2020 Oct;84:84-95. doi: 10.1016/j.medengphy.2020.07.026. Epub 2020 Aug 1.
Bi-condylar tibial plateau fractures are demanding to treat due to the complex geometry and the articular comminution. The presence of a coronal fracture line plays a crucial role in the fixation strategy. Disregarding this fracture line in previous biomechanical studies and established fracture classifications resulted in a lack of detailed knowledge regarding the influence of medial-posterior fragments on implant load sharings. This study aimed to evaluate the effects of coronal splits on stress distributions within the implants using the finite element analysis (FEA). FE models with (Fracture C) and without the coronal split (Fracture H) were developed and validated in order to assess stress distributions within the implant components. Comparing FE outcomes with biomechanical experiments indicated that both fracture models were well validated. FE evaluations demonstrated that the coronal split caused destabilization of the medial tibia, as well as a shift in the peak-stress areas from the middle part of the plate to the proximal section, and a 61% increase in the maximum stress of the kick-stand screw. Therefore, FE models based on clinically-relevant fracture morphologies can provide a reliable tool to assess implant failures as well as to compare different fracture fixation techniques.
双髁胫骨平台骨折因其复杂的几何形状和关节粉碎而难以治疗。冠状骨折线的存在在固定策略中起着关键作用。在以往的生物力学研究和既定的骨折分类中忽略这条骨折线，导致缺乏关于内侧后段碎片对植入物负荷分担影响的详细知识。本研究旨在使用有限元分析（FEA）评估冠状骨折对植入物内应力分布的影响。开发并验证了有冠状骨折（骨折C）和无冠状骨折（骨折H）的有限元模型，以评估植入物组件内的应力分布。将有限元分析结果与生物力学实验进行比较表明，两种骨折模型均得到了良好验证。有限元分析评估表明，冠状骨折导致胫骨内侧不稳定，以及峰值应力区域从钢板中部向近端转移，并且支脚螺钉的最大应力增加了61%。因此，基于临床相关骨折形态的有限元模型可以提供一个可靠的工具，用于评估植入物失效以及比较不同的骨折固定技术。
