Yang Shan-Wei, Kuo Shyh Ming, Chang Shwu Jen, Su Tian-Shiang, Chen Hsiang-Ho, Renn Jenn-Huei, Lin Ting-Sheng
Orthopedics. 2013 Oct 1;36(10):e1316-21. doi: 10.3928/01477447-20130920-26.
The goal of this study was to compare the biomechanical stability of cannulated locking screws and noncannulated cortical locking screws in a periarticular locking plate. Twelve fresh-frozen porcine tibias with a 1-cm gap created distal to the tibial plateau were used to simulate an unstable proximal tibial fracture. All specimens were fixed with a periarticular proximal lateral tibial locking plate and divided into 2 groups based on whether the proximal metaphyseal screw holes of the plate were inserted with either cannulated locking screws or noncannulated cortical locking screws. An axial compressive load was applied to cause failure in each specimen using a materials testing instrument. The axial stiffness and maximum failure strength in axial loading were recorded. Axial stiffness of the constructs using noncannulated cortical locking screw was significantly higher than that of the constructs using cannulated locking screws (P=.006). Axial failure strength of the constructs using noncannulated cortical locking screw was significantly higher than that of the constructs using cannulated locking screws (P=.002). The failure mode observed in all specimens was a permanent screw-bending deformity over the head-shaft junction of proximal metaphyseal screws, irrespective of whether they were cannulated or noncannulated cortical locking screws. Fixation with noncannulated cortical locking screws offered more stability than cannulated locking screws with regard to axial stiffness and failure strength in a porcine model with unstable proximal tibial fractures.
本研究的目的是比较空心锁定螺钉和非空心皮质锁定螺钉在关节周围锁定钢板中的生物力学稳定性。使用12根新鲜冷冻的猪胫骨，在胫骨平台远端制造1厘米的间隙，以模拟不稳定的胫骨近端骨折。所有标本均用关节周围近端外侧胫骨锁定钢板固定，并根据钢板近端干骺端螺钉孔插入的是空心锁定螺钉还是非空心皮质锁定螺钉分为两组。使用材料测试仪器对每个标本施加轴向压缩载荷以导致失效。记录轴向加载时的轴向刚度和最大失效强度。使用非空心皮质锁定螺钉的结构的轴向刚度显著高于使用空心锁定螺钉的结构（P = 0.006）。使用非空心皮质锁定螺钉的结构的轴向失效强度显著高于使用空心锁定螺钉的结构（P = 0.002）。在所有标本中观察到的失效模式是近端干骺端螺钉头-干交界处的永久性螺钉弯曲变形，无论它们是空心还是非空心皮质锁定螺钉。在不稳定的胫骨近端骨折猪模型中，就轴向刚度和失效强度而言，使用非空心皮质锁定螺钉固定比空心锁定螺钉提供了更高的稳定性。
