Hakało Jerzy, Pezowicz Celina, Wroński Jerzy, Bedziński Romuald, Kasprowicz Magdalena
Neurol Neurochir Pol. 2007 Sep-Oct;41(5):411-6.
Clinical observations show that subsidence of cervical interbody implants takes place in the early postoperative period. Additional plating or use of a plate-cage is thought to be helpful to avoid excessive subsidence. We performed a biomechanical comparative study to assess the process of subsidence after the use of three different cervical stabilization methods.
Porcine cervical specimens after anterior discectomy were stabilized by a cage alone (n=6), cage with plate (n=6) and a plate-cage (n=6), and were exposed to 21 000 cycles of 20-200 N cyclic axial loads with frequency of 2.5 Hz. Size of subsidence was continually calculated by the software of the testing machine. One-way ANOVA test was applied for statistical evaluation.
The test revealed two phases in the course of subsidence: an initial phase and a final one. In the initial phase rapid increase of subsidence occurred. Velocity and size of subsidence in this phase differed significantly between the stabilizing systems. The fastest and biggest subsidence occurred in the case of the cage alone, less subsidence was noted for the cage with plate and the least for the plate-cage. The final phase of the subsidence was markedly slower and longer. Velocity and size in this phase were the biggest for the cage alone. The differences between the cage with plate and the plate-cage in that phase were not significant.
The study shows that subsidence occurs in two phases irrespective of the type of cervical stabilization and this finding confirms similar clinical observations. Additional plating can be helpful in controlling the course of subsidence.
临床观察表明，颈椎椎间融合器在术后早期会发生下沉。额外使用钢板或采用钢板 - 融合器被认为有助于避免过度下沉。我们进行了一项生物力学对比研究，以评估三种不同颈椎稳定方法使用后下沉的过程。
对猪颈椎前路椎间盘切除术后的标本分别采用单纯融合器（n = 6）、融合器加钢板（n = 6）和钢板 - 融合器（n = 6）进行固定，并使其承受频率为2.5 Hz、大小为20 - 200 N的21000次循环轴向载荷。通过试验机软件持续计算下沉尺寸。采用单因素方差分析进行统计学评估。
试验揭示了下沉过程中的两个阶段：初始阶段和最终阶段。在初始阶段，下沉迅速增加。此阶段不同稳定系统的下沉速度和尺寸差异显著。单纯融合器的下沉速度最快且下沉量最大，融合器加钢板的下沉量较小，钢板 - 融合器的下沉量最小。下沉的最终阶段明显更慢且持续时间更长。此阶段单纯融合器的下沉速度和尺寸最大。融合器加钢板与钢板 - 融合器在此阶段的差异不显著。
该研究表明，无论颈椎稳定方法的类型如何，下沉均分为两个阶段，这一发现证实了类似的临床观察结果。额外使用钢板有助于控制下沉过程。
