肌肉短距离硬度表现得像麦克斯韦尔元件,而不是弹:对关节稳定的影响
Jeff M Barrett1,2, Masoud Malakoutian2,3, Sidney Fels4
1Department of Orthopaedics, The University of British Columbia, British Columbia, Canada.
PloS one
|August 14, 2024
概括
肌肉的短期硬不仅仅确保了关节的稳定性. 模拟显示,单靠这种机制无法防止关节的不稳定,这表明其他因素对于保持姿势至关重要.
科学领域:
- 生物力学 生物力学
- 人体生理学 人体生理学
- 计算机建模 计算建模
背景情况:
- 肌肉对于日常活动中的关节稳定至关重要,部分原因是短程硬 (SRS).
- 当活动肌肉伸展超过预测的力量-长度关系时,SRS会产生更大的力.
- 理论上,SRS是关节稳定的一个关键机制.
研究的目的:
- 调查显示SRS的哈克斯利型肌肉模型是否可以在持续激活下稳定关节.
- 测试SRS单独提供关节稳定性的假设,使用前向动态模拟.
主要方法:
- 一个倒置的摆形模型 (惯性时刻:2.7公斤平方米) 包含了哈克斯利类型的肌肉模型.
- 模拟分析了对5Nm平方波扰动 (50毫秒持续时间) 的关节稳定性.
- 稳定肌肉力量的计算是基于最小化潜在能量的计算.
主要成果:
- 倒置的摆形模型表现出不稳定性,并未能保持直立的姿势.
- 尽管最初预测通过对手和对手肌肉协同激活的稳定性,但这种情况发生了.
- 即使肌肉完全激活,模型仍然不稳定.
结论:
- 仅仅是短距离的刚性对关节的稳定性是不够的,即使有轻微的干扰.
- SRS的动态与典型的弹不同;将其建模为麦克斯韦元件 (系列弹阻尼器) 更合适.
- 从SRS减轻可能允许中枢神经系统反应时间,和其他因素,如反射可能有助于关节的稳定性.
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