Polly D W, Klemme W R, Cunningham B W, Burnette J B, Haggerty C J, Oda I
Orthopaedic Surgery Service, Walter Reed Army Medical Center, Washington, DC 20310, USA.
J Spinal Disord. 2000 Feb;13(1):58-62. doi: 10.1097/00002517-200002000-00012.
This study examines the biomechanical effects of interbody cages and variations in posterior rod diameter in a simulated single-level spinal fusion. A single-level spinal fusion model composed of polyethylene cylinders, posterior pedicular instrumentation, and variously positioned single or dual interbody cages was used for biomechanical testing. Constructs were tested under compressive flexural load, with measurement of stiffness, rod strain, cage strain, and intracage pressure. A strong linear correlation emerged between the mean construct stiffness and cage positioning within the sagittal plane that was inversely related to posterior rod strain. Two small titanium mesh cages were equivalent to one large cage. In a single-level spine model, the presence of and sagittal position of interbody cages significantly influences overall construct stiffness. Cage strain increased with more anterior positions and was inversely related to rod strain.
本研究在模拟单节段脊柱融合中，考察椎间融合器及后路棒直径变化的生物力学效应。使用由聚乙烯圆柱体、后路椎弓根内固定器械以及不同位置的单个或双个椎间融合器组成的单节段脊柱融合模型进行生物力学测试。在压缩弯曲载荷下对结构进行测试，测量其刚度、棒应变、融合器应变及融合器内压力。平均结构刚度与矢状面内融合器位置之间呈现出强线性相关性，且与后路棒应变呈负相关。两个小型钛网融合器等同于一个大型融合器。在单节段脊柱模型中，椎间融合器的存在及其矢状位置显著影响整体结构刚度。融合器应变随位置更靠前而增加，且与棒应变呈负相关。
