Department of Orthopaedic Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
Institute for Material Research, Tohoku University, Sendai, Miyagi, Japan.
J Biomed Mater Res B Appl Biomater. 2018 Nov;106(8):2841-2848. doi: 10.1002/jbm.b.34064. Epub 2018 Jan 23.
The influence of Young's moduli of materials on the fracture healing process remains unclear. This study aimed to assess the effects of intramedullary nails composed of materials with low Young's moduli on fracture repair. We previously developed a β-type Ti-Nb-Sn alloy with low Young's modulus close to that of human cortical bone. Here, we prepared two Ti-Nb-Sn alloys with Young's moduli of 45 and 78 GPa by heat treatment, and compared their effects on fracture healing. Fracture and nailing were performed in the right tibiae of C57BL/6 mice. The bone healing process was evaluated by microcomputed tomography (micro-CT), histomorphometry, and RT-PCR. We found larger bone volumes of fracture callus in the mice treated with the 45-GPa Ti-Nb-Sn alloy as compared with the 78-GPa Ti-Nb-Sn alloy in micro-CT analyses. This was confirmed with histology at day 14, with accelerated new bone formation and cartilage absorption in the 45-GPa Ti-Nb-Sn group compared with the 78-GPa Ti-Nb-Sn group. Acp5 expression was lower in the 45-GPa Ti-Nb-Sn group than in the 78-GPa Ti-Nb-Sn group at day 10. These findings indicate that intramedullary fixation with nails with a lower Young's modulus offer a greater capacity for fracture repair. Our 45-GPa Ti-Nb-Sn alloy is a promising material for fracture treatment implants. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2841-2848, 2018.
材料的杨氏模量对骨折愈合过程的影响尚不清楚。本研究旨在评估杨氏模量低的髓内钉对骨折修复的影响。我们之前开发了一种接近人皮质骨杨氏模量的低杨氏模量β型 Ti-Nb-Sn 合金。在此，我们通过热处理制备了杨氏模量分别为 45 和 78 GPa 的两种 Ti-Nb-Sn 合金，并比较了它们对骨折愈合的影响。在 C57BL/6 小鼠的右侧胫骨中进行骨折和钉固定。通过 microCT（micro-CT）、组织形态计量学和 RT-PCR 评估骨愈合过程。我们发现，在用 45-GPa Ti-Nb-Sn 合金处理的小鼠中，骨折痂的骨体积大于用 78-GPa Ti-Nb-Sn 合金处理的小鼠。 micro-CT 分析在第 14 天的组织学检查中得到证实，45-GPa Ti-Nb-Sn 组的新骨形成和软骨吸收加速，而 78-GPa Ti-Nb-Sn 组则加速。与 78-GPa Ti-Nb-Sn 组相比，45-GPa Ti-Nb-Sn 组在第 10 天的 Acp5 表达水平较低。这些发现表明，具有较低杨氏模量的髓内固定钉具有更大的骨折修复能力。我们的 45-GPa Ti-Nb-Sn 合金是一种有前途的骨折治疗植入物材料。 © 2018 Wiley Periodicals, Inc. J 生物医学材料 Res 部分 B: 应用生物材料，106B：2841-2848，2018。
