Shanghai YangZhi Rehabilitation Hospital (Shanghai Sunshine Rehabilitation Center), School of Medicine, Tongji University, Shanghai 200092, China; Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of the Ministry of Education, Tongji Hospital, School of Medicine, Tongji University, 389 Xincun Road, Shanghai 200065, China.
Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of the Ministry of Education, Tongji Hospital, School of Medicine, Tongji University, 389 Xincun Road, Shanghai 200065, China.
Med Eng Phys. 2023 Nov;121:104062. doi: 10.1016/j.medengphy.2023.104062. Epub 2023 Oct 13.
Ossification of the ligamentum flavum (OLF) is thought to be an influential etiology of myelopathy, as thickened ligamentum flavum causes the stenosis of the vertebral canal, which could subsequently compress the spinal cord. Unfortunately, there was little information available on the effects of cervical OLF on spinal cord compression, such as the relationship between the progression of cervical OLF and nervous system symptoms during dynamic cervical spine activities. In this research, a finite element model of C1-C7 including the spinal cord featured by dynamic fluid-structure interaction was reconstructed and utilized to analyze how different types of cervical OLF affect principal strain and stress distribution in spinal cord during spinal activities towards six directions. For patients with cervical OLF, cervical extension induces higher stress within the spinal cord among all directions. From the perspective of biomechanics, extension leads to stress concentration in the lateral corticospinal tracts or the posterior of gray matter. Low energy damage to the spinal cord would be caused by the high and fluctuating stresses during cervical movements to the affected side for patients with unilateral OLF at lower grades.
黄韧带骨化（OLF）被认为是脊髓病的一个重要病因，因为增厚的黄韧带会导致椎管狭窄，从而压迫脊髓。不幸的是，关于颈椎 OLF 对脊髓压迫的影响的信息很少，例如颈椎 OLF 的进展与颈椎活动期间神经系统症状之间的关系。在这项研究中，重建了包括脊髓在内的 C1-C7 的有限元模型，该模型具有动态流固耦合特性，用于分析不同类型的颈椎 OLF 在六个方向的脊柱活动期间如何影响脊髓中的主应变和应力分布。对于患有颈椎 OLF 的患者，颈椎伸展在所有方向中都会导致脊髓内更高的应力。从生物力学的角度来看，伸展会导致侧皮质脊髓束或灰质后部的应力集中。对于单侧 OLF 程度较低的患者，颈椎向患侧运动时，高且波动的应力会导致脊髓产生低能量损伤。
