Peña E, Calvo B, Martínez M A, Doblaré M
Department of Mechanical Engineering, University of Zaragoza, María de Luna, 3, E-50018 Zaragoza, Spain.
Comput Biol Med. 2008 Jan;38(1):69-81. doi: 10.1016/j.compbiomed.2007.07.003. Epub 2007 Sep 14.
It is commonly accepted that total or partial meniscectomies cause wear of articular cartilages that leads to severe damage in a period of few years. This also produces alteration of the biomechanical environment and increases articular instability, with a progressive and degenerative arthrosic pathology. Due to these negative consequences, total meniscectomy technique has been avoided, with a clear preference for partial meniscectomies. Despite the better results obtained with this latter technique, it has been demonstrated that the knee still suffers progressive long-term wear, which alters the properties of the surface of articular cartilage. In this paper, a phenomenological isotropic damage model of articular cartilage is presented and implemented in a finite element code. We hypothesized that there is a relation between the increase of shear stress and cartilage degeneration. To confirm the hypothesis, the obtained results were compared to experimental ones. It is used to investigate the effect of meniscectomies on articular damage in the human knee joint. Two different situations were compared for the tibio-femoral joint: healthy and after meniscectomy. The distribution of damaged regions and the damage level distribution resulted qualitatively similar to experimental results, showing, for instance that, after meniscectomy, significant degeneration occurs in the lateral compartment. A noteworthy result was that patterns of damage in a total meniscectomy model give better agreement to clinical results when using relative increases in shear stress, rather than an absolute shear stress criterion. The predictions for partial meniscectomies indicated the relative severity of the procedures.
人们普遍认为，全半月板切除术或部分半月板切除术会导致关节软骨磨损，在几年内造成严重损伤。这还会改变生物力学环境，增加关节不稳定，引发进行性和退行性关节病理变化。由于这些负面后果，全半月板切除术技术已被避免，人们明显更倾向于部分半月板切除术。尽管后一种技术取得了更好的效果，但已证明膝关节仍会遭受长期的渐进性磨损，这会改变关节软骨表面的特性。在本文中，提出了一种关节软骨的唯象各向同性损伤模型，并在有限元代码中实现。我们假设剪切应力的增加与软骨退变之间存在关联。为了证实这一假设，将所得结果与实验结果进行了比较。它用于研究半月板切除术对人体膝关节关节损伤的影响。对胫股关节比较了两种不同情况：健康状态和半月板切除术后。损伤区域的分布和损伤程度分布在定性上与实验结果相似，例如表明，半月板切除术后，外侧间室会发生明显退变。一个值得注意的结果是，当使用剪切应力的相对增加而不是绝对剪切应力标准时，全半月板切除模型中的损伤模式与临床结果的一致性更好。部分半月板切除术的预测结果表明了手术的相对严重程度。
