Investigation of the mechanical regulation of lumbar inter-corporeal spinal fusion

椎间盘退变是引起特定下腰痛的最常见原因之一。由于多种原因，退变可导致节段失稳。前路椎体间融合术是目前纠正节段不稳最有效的外科治疗方法。在大多数情况下，椎间融合器结合自体松质骨用于实现一个或多个椎体节段的永久性骨性融合。脊柱融合最常见的并发症之一是骨不连，通常是由于机械(如不稳定、超负荷、应力遮挡)和生物学(如限制血管形成)的原因。因此，硬质植入物的插入减少了融合区中骨形成所需的机械刺激。这可能导致早期植入失败、植入物失去稳定性或错位以及疼痛，并伴随着相当大的健康风险和重新手术的必要性。因此，本研究的主要目的是探讨腰椎峡部裂术后腰椎融合的力学规律。为此，将开发包含影响融合过程的力学和生物因素的腰椎运动节段的有限元模型。这一知识将使我们能够确定导致某些患者延迟愈合或骨不连的因素。此外，Cage还将针对腰椎进行优化，与临床上可用的植入物相比，这将显著增强骨骼固定并缩短完全骨融合所需的时间。这应该会减少骨不连和翻修手术的风险，以及相关的医疗费用。

The degeneration of the intervertebral disc is one of the most common causes of specific lower back pain. Due to multiple reasons, degeneration can lead to segmental instability. Anterior inter-corporeal spinal fusion is currently the most effective surgical treatment to correct segmental instability. In most cases, a spinal cage in combination with autogenous cancellous bone is used to achieve a permanent bony fusion of one or more vertebral segments. One of the most common complications of spinal fusion is nonunion, often due to mechanical (e.g., instabilities, overloading, stress shielding) and biological (e.g., restricted vascularization) reasons. Thereby, the insertion of a rigid implant causes a reduction in the mechanical stimulus required for bone formation in the fusion region. This can result in early implant failure, loss of stability or malposition of the implant and pain; associated with considerable health risks and the necessity for re-operation.The process of bone formation during inter-corporeal spinal fusion is poorly understood. Therefore, the main goal of this research project is to investigate the mechanical regulation of lumbar spinal fusion following spondylodesis. For this purpose, finite element models of lumbar motion segments will be developed, that incorporate the mechanical and biological factors influencing the fusion process. This knowledge will allow us to identify factors contributing to delayed healing or nonunions in some patients. In addition, cages will be optimized for the lumbar spine, which will significantly enhance skeletal fixation and reduce the time required for complete bony fusion compared to clinically available implants. This should reduce the risk of non-unions and revision surgeries as well as the associated health care costs.