Ordonez Diaz Tamara, Nichols Jennifer A
J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA.
J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA.
J Biomech. 2021 Jun 23;123:110498. doi: 10.1016/j.jbiomech.2021.110498. Epub 2021 May 14.
Musculoskeletal models and computer simulations enable non-invasive study of muscle function and contact forces. Hand models are useful for understanding the complexities of hand strength, precision movement, and the dexterity required during daily activities. Yet, generic models fail to accurately represent the entire scope of the population, while subject-specific models are labor-intensive to create. The objective of this study was to assess the efficacy of scaled generic models to represent the broad spectrum of strength profiles across the lifespan. We examined one hundred lateral pinch simulations using a generic model of the wrist and thumb anthropometrically scaled to represent the full range of heights reported for four ages across childhood, puberty, older adolescence, and adulthood. We evaluated maximum lateral pinch force produced, muscle control strategies, and the effect of linearly scaling the maximum isometric force. Our simulations demonstrated three main concepts. First, anthropometric scaling could capture age-dependent differences in pinch strength. Second, a generic muscle control strategy is not representative of all populations. Lastly, simulations do not employ optimal fiber length to complete a lateral pinch task. These results demonstrate the potential of anthropometrically-scaled models to study hand strength across the lifespan, while also highlighting that muscle control strategies may adapt as we age. The results also provide insight to the force-length relationship of thumb muscles during lateral pinch. We conclude that anthropometric scaling can accurately represent age characteristics of the population, but subject-specific models are still necessary to represent individuals.
肌肉骨骼模型和计算机模拟能够对肌肉功能和接触力进行非侵入性研究。手部模型有助于理解手部力量、精确运动以及日常活动所需灵活性的复杂性。然而，通用模型无法准确呈现整个人口群体的情况，而针对个体的模型创建起来又耗费人力。本研究的目的是评估按比例缩放的通用模型在呈现不同年龄段广泛力量特征方面的有效性。我们使用一个手腕和拇指的通用模型进行了100次侧捏模拟，该模型在人体测量学上进行了缩放，以代表儿童期、青春期、青少年晚期和成年期四个年龄段所报告的全部身高范围。我们评估了产生的最大侧捏力、肌肉控制策略以及线性缩放最大等长力的效果。我们的模拟展示了三个主要概念。首先，人体测量学缩放能够捕捉捏力强度中与年龄相关的差异。其次，通用的肌肉控制策略并不代表所有人群。最后，模拟在完成侧捏任务时并未采用最佳纤维长度。这些结果证明了按人体测量学缩放的模型在研究不同年龄段手部力量方面的潜力，同时也凸显出肌肉控制策略可能会随着年龄增长而变化。这些结果还为侧捏过程中拇指肌肉的力-长度关系提供了见解。我们得出结论，人体测量学缩放能够准确代表人群的年龄特征，但要代表个体仍需要针对个体的模型。
