Investigation of possible causal relationships between disc and facet joint degeneration using in-vivo, in vitro and finite element analyses

椎间盘和关节突关节的退变是引起特定腰痛的一个主要原因，除了其他因素外，不适当的机械应力和超载也会引起腰痛。哪个结构首先受到退化过程的影响以及两者之间是否存在相关性，这仍然是一个争论的问题。然而，这些知识对于选择适当的治疗策略至关重要。它提供了优化脊柱植入物发展的基本知识，并有助于决定融合或保持运动的植入物的适应症。本研究项目的目的是利用体内、体外和计算机方法阐明功能性脊柱单位的退变过程。绵羊体内动物实验将通过进行各种外科手术来启动椎间盘和/或小关节退变。在一年的时间里，将研究每一种随后的退行性变化的相互影响。以下体外实验将用于检测受影响部分的形态学变化，并将现实的几何形状和材料参数实现到开发的有限元模型中。考虑到个体脊柱形态，有限元分析将为人类退行性过程的过程提供有价值的线索，并试图阐明椎间盘和小关节的病理变化之间所谓的力学相关性。

The degeneration of the intervertebral disc and the facet joints is one major reason for specific low back pain which can be induced, among other factors, by inappropriate mechanical stresses and overloading. It is still a matter of debate which structure is affected first by degenerative processes and whether a correlation exists between both. This knowledge, however, is crucial for the choice of appropriate treatment strategies. It provides basic know-how to optimize the development of spinal implants and helps to take a decision regarding the indication of fusion or motion-preserving implants.The aim of this research project is to clarify the course of degeneration within a functional spinal unit using an in vivo, in vitro and in silico approach. The in vivo animal experiment on sheep will be used to initiate an intervertebral disc and/or facet joint degeneration by performing various surgical procedures. Over a period of one year, the mutual influence of each of the subsequent degenerative changes will be investigated. The following in vitro experiments will be used to detect morphological changes within affected segments and to implement realistic geometry and material parameters into the developed finite element models. The finite element analyzes will offer valuable clues about the course of degenerative processes in humans taking into account individual spine morphologies and try to elucidate alleged mechanical correlations between pathologic changes of the intervertebral disc and the facet joints.