数学理由的选择杆子的外部固定设备的多结构性骨盆损伤的设备
Georgian medical news
|October 8, 2023
概括
盆腔外部固定中的形棒可以降低压力度,特别是在骨质疏松性骨中. 这项生物机械研究表明,它们对骨盆骨质合成的强度有所提高.
科学领域:
- 生物力学 生物力学
- 整形外科手术 整形外科手术
- 有限元分析 有限元分析
背景情况:
- 外部骨盆骨质合成对于治疗骨盆骨折至关重要,特别是在骨质疏松症患者中.
- 在外部固定下了解骨盆的压力-应变状态 (SSS) 对于优化治疗结果至关重要.
- 目前的外部固定装置使用圆柱形杆,但它们在骨质疏松性骨中的生物机械性能需要进一步研究.
研究的目的:
- 在骨质疏松症中生物力学证实外焦骨盆骨质合成的使用.
- 为了研究和比较骨盆的压力-应变状态,使用外部固定装置,使用圆柱形和形棒.
- 评估形棒在减轻正常和骨质疏松的骨盆骨模型中的压力度方面的有效性.
主要方法:
- 使用有限元法 (FEM) 来建模盆骨在外部固定下的压力-应变状态.
- 使用断层扫描数据构建了骨盆的详细几何模型,其中包括各种骨和软骨组织.
- 对正常骨和骨质疏松症骨模型进行了模拟,在模拟体重负荷为700N的情况下,使用圆柱形和形棒进行外部固定,模拟体重负荷为700N.
主要成果:
- 在正常的骨头中,圆柱形杆在螺杆入口点 (18.5 MPa) 和稀薄的腹翼区域 (8.1 MPa) 显示了应力度. 形棒将这些压力降低到分别为16.4 MPa和6.3 MPa.
- 在骨质疏松性骨中,圆柱形棒导致更高的应力度 (28.4 MPa在螺丝入口,9.1 MPa在稀疏区域). 形棒将这些压力降低到26.5MPa和7MPa.
- 与圆柱形棒相比,形棒在两种骨状况中始终表现出较低的应力-应变状态和较小的应力度区域.
结论:
- 在外部骨盆固定装置中使用形棒显著降低了应力度,特别是在螺丝插入和稀疏骨区域等关键点.
- 形棒在"骨盆 - 棒"系统中提供了改进的生物力学性能,对患有骨质疏松性骨组织的患者尤其有益.
- 这些发现支持了对外骨盆固定中的形棒进行临床测试的建议,以改善复杂骨盆骨折的治疗结果.
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