Simon U, Augat P, Utz M, Claes L
Scientific Computing Centre Ulm, Institute of Orthopaedic Research and Biomechanics, University of Ulm, Helmholtzstraße 20, Ulm, Germany.
Comput Methods Biomech Biomed Engin. 2011;14(1):79-93. doi: 10.1080/10255842.2010.499865. Epub 2010 Nov 1.
A dynamic model was developed to simulate complex interactions of mechanical stability, revascularisation and tissue differentiation in secondary fracture healing. Unlike previous models, blood perfusion was included as a spatio-temporal state variable to simulate the revascularisation process. A 2D, axisymmetrical finite element model described fracture callus mechanics. Fuzzy logic rules described the following biological processes: angiogenesis, intramembranous ossification, chondrogenesis, cartilage calcification and endochondral ossification, all of which depended on local strain state and local blood perfusion. In order to evaluate how the predicted revascularisation depended on the mechanical environment, we simulated two different healing cases according to two groups of transverse metatarsal osteotomies in sheep with different axial stability. The model predicted slower revascularisation and delayed bony bridging for the less stable case, which corresponded well to the experimental observations. A revascularisation sensitivity analysis demonstrated the potential of the model to account for different conditions regarding the blood supply.
开发了一个动态模型来模拟二次骨折愈合过程中机械稳定性、血管再生和组织分化的复杂相互作用。与之前的模型不同，血液灌注被作为一个时空状态变量纳入，以模拟血管再生过程。一个二维轴对称有限元模型描述了骨折痂力学。模糊逻辑规则描述了以下生物过程：血管生成、膜内成骨、软骨生成、软骨钙化和软骨内成骨，所有这些过程都依赖于局部应变状态和局部血液灌注。为了评估预测的血管再生如何依赖于机械环境，我们根据绵羊两组具有不同轴向稳定性的横行跖骨截骨术模拟了两种不同的愈合情况。该模型预测，稳定性较差的情况下血管再生较慢且骨桥接延迟，这与实验观察结果非常吻合。血管再生敏感性分析证明了该模型考虑不同血液供应条件的潜力。
