用个性化有限元素建模,脚螺丝错位对拉出强度的影响
A Rouyin1, H Nazemi1, N Arjmand1
1Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran.
Computers in biology and medicine
|October 20, 2024
概括
即使是轻微的脊柱脚螺丝错位,在临床上被认为是安全的,也会显著降低螺丝的拉出强度. 这增加了术后松的风险,突出了先进的安置技术的需要.
科学领域:
- 脊柱外科手术 脊柱外科手术
- 生物机械工程 生物机械工程
- 整形外科的研究研究.
背景情况:
- 在手术过程中,脊椎脚螺丝错位是脊髓融合手术中常见的问题.
- 临床上可接受的错位 (高达4毫米) 可能会损害螺丝的稳定性,增加松动的风险.
- 准确的拉出强度评估对于了解螺丝固定完整性至关重要.
研究的目的:
- 使用患者特定的有限元素 (FE) 建模,比较理想位置的拉出强度与错位的脚螺丝.
- 量化不同错位类型 (中间,侧面) 和严重程度对螺丝固定的影响.
- 评估小错位对螺丝稳定的临床相关性.
主要方法:
- 基于对健康个体的CT成像,开发了腰椎 (L1-L5) 的3D FE模型.
- 在四个条件下对脚螺丝进行模拟的拉出测试:理想放置和三个错位场景 (小中位,小侧,严重侧).
- 通过将预测的拉出力与现有的实验数据进行比较,验证了FE模型,并将基于应变的损伤模型纳入骨折模拟.
主要成果:
- 针对实验范围 (15832412 N) 验证的理想位置螺丝的FE预测的拉出力.
- 与理想位置相比,所有错位组的平均拉出力显著减少 (p < 0.05).
- 轻微的中间部位错位减少了20%,轻微的侧部位错位减少了22%,严重的侧部位错位减少了37%.
结论:
- 即使在临床上可以接受的脚螺丝错位 (高达4毫米) 也会显著降低拉出强度.
- 减少拉出强度会增加术后螺丝松动的风险.
- 踏板螺丝安置的先进技术对于减轻与常见错位相关的风险至关重要.
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