肩部假肢茎长度对由于扭力负荷而导致的故障的影响. 一个生物力学研究的复合体
Weston K Ryan1, Wyatt D Vander Voort1, Maarouf A Saad1
1Department of Orthopaedics, University of California, Davis, Sacramento, CA, USA.
JSES international
|September 18, 2023
概括
肩关节整形干的设计影响扭力强度. 与短茎和长茎设计相比,无茎植入物不那么刚硬,在较低的扭矩下失败,这可能会影响周围假肢骨折风险.
科学领域:
- 整形外科手术 整形外科手术
- 生物机械工程 生物机械工程
- 材料科学 材料科学 材料科学
背景情况:
- 肩关节整形越来越常见,可提供各种关节茎设计.
- 无茎和短茎植入物提供了优势,如减少骨移除和更好的解剖适应.
- 不同的茎设计对扭转负荷的生物力学反应及其与周围假肢骨折的关联需要评估.
研究的目的:
- 在扭力负荷下生物机械评估合成部与长茎,短茎和无茎肩关节整形组件.
- 描述不同骨干设计的故障机制和扭转反应.
- 评估茎设计是否有可能影响周围假肢骨折风险.
主要方法:
- 二十四个人造部被植入了长茎,短茎或无茎的非水泥假肢 (每组n=8).
- 在20N的轴向力后,样本在15度/秒的速度下受到扭转负荷的损坏.
- 使用ANOVA测量和分析了机械性能,包括刚性,屈服扭矩,最终强度和故障负载.
主要成果:
- 与短茎和无茎设计相比,长茎植入物表现出明显更大的刚性.
- 与短茎植入物相比,无茎植入物表现出较低的产量扭矩和产量能量.
- 短茎和长茎植入物显示出比无茎植入物显著更高的最大扭矩和失效扭矩.
结论:
- 无茎肩关节整形植入物不那么硬,并且在较低的扭力负载下失败,而不是与茎设计相比.
- 无茎植入物的失败机制突出显示了骨质和骨固定在代谢中的作用.
- 关节茎的设计是实现扭转稳定的关键因素,并减轻肩膀关节整形手术中周围假肢骨折的风险.
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