PDF(Pubmed)
Abstract：
Introduction: Bone healing can be improved by axial micromovement, as has been shown in animals and human patients with external fixators. In the development of smart fracture plates, the ideal amount of stroke for different fracture types in the different healing stages is currently unknown. It was hypothesized that the resulting strain in the fracture gap of a simple tibial shaft fracture does not vary with the amount of axial stroke in the plate, the fracture gap size, and the fracture angle. Methods: With finite element simulations based on body donation computed tomography data, the second invariant of the deviatoric strain tensor (J2), strain energy density, hydrostatic strain, octahedral shear strain, and percentage of the fracture gap in the \"perfect healing window\" were computed for different gap sizes (1-3 mm), angles (5°-60°), and plate stroke levels (0.05-0.60 mm) in three healing stages. Multiple linear regression analyses were performed. Results: Findings showed that an active fracture plate should deliver an axial stroke in the range of 0.10-0.45 mm. Different optimal stroke values were found for each healing phase, namely, 0.10-0.25 mm for the first, 0.10 mm for the second, and 0.35-0.45 mm for the third healing phase, depending on the fracture gap size and less on the fracture angle. J2, hydrostatic strain, octahedral shear strain and the strain energy density correlated with the fracture gap size and angle (all p < 0.001). The influence of the fracture gap size and angle on the variability (adjusted R2) in several outcome measures in the fracture gap was shown to vary throughout healing. The contribution to the variability of the percentage of the fracture gap in the perfect healing window was greatest during the second healing phase. For J2, strain energy density, hydrostatic strain, and octahedral shear strain, the fracture gap size showed the greatest contribution in the third fracture healing phase, while the influence of fracture angle was independent of the healing phase. Discussion: The present findings are relevant for implant development and to design clinical studies that aim to accelerate fracture healing using axial micromovement.
摘要：
简介：轴向微运动可以改善骨愈合，正如在具有外部固定器的动物和人类患者中所显示的那样。在智能骨折板的发展中，目前尚不清楚不同骨折类型在不同愈合阶段的理想卒中数量.假设简单的胫骨干骨折的骨折间隙中产生的应变不随钢板中轴向行程的量而变化。裂缝间隙大小，和骨折角度。方法：基于人体捐献计算机断层扫描数据进行有限元模拟，偏应变张量的第二不变量(J2)，应变能密度，静水压应变,八面体剪切应变,对于不同的间隙尺寸（1-3mm），计算了“完美愈合窗口”中骨折间隙的百分比，角度(5°-60°),三个愈合阶段的板行程水平（0.05-0.60mm）。进行多元线性回归分析。结果：研究结果表明，活动骨折钢板的轴向行程范围应为0.10-0.45mm。每个愈合阶段都有不同的最佳中风值，即,对于第一个0.10-0.25毫米，秒为0.10毫米，第三个愈合阶段为0.35-0.45毫米，取决于断裂间隙的大小和较小的断裂角度。J2,静水压应变,八面体剪切应变和应变能密度与断裂间隙大小和角度相关（均p<0.001）。在骨折间隙的几种结果测量中，骨折间隙的大小和角度对变异性（调整后的R2）的影响在整个愈合过程中都有所不同。在第二愈合阶段，完美愈合窗口中骨折间隙百分比的变异性的贡献最大。对于J2，应变能密度，静水压应变,八面体剪切应变，骨折间隙大小在第三个骨折愈合阶段显示出最大的贡献，而骨折角度的影响与愈合阶段无关。讨论：目前的发现与植入物的开发和设计旨在通过轴向微运动加速骨折愈合的临床研究有关。
