Shojaeizadeh Maedeh, Spartacus Victoria, Sparrey Carolyn J
Mechatronic Systems Engineering, Simon Fraser University, Surrey, BC V3T 0A3, Canada.
Mechatronic Systems Engineering, Simon Fraser University, Surrey, BC V3T 0A3, Canada; International Collaboration on Repair Discoveries (ICORD), Vancouver, BC V5Z 1M9, Canada.
J Biomech Eng. 2023 Feb 1;145(2). doi: 10.1115/1.4055562.
In vivo characteristics of palmar soft tissue can be used to improve the accuracy of human models to explore and simulate a range of contact scenarios. Tissue characteristics can help to assess injury prevention strategies and designing technologies that depend on quantified physical contacts such as prosthetics, wearables, and assistive devices. In this study, a simplified quasi-linear viscoelastic (QLV) model was developed to quantify large deformation, in vivo soft tissue relaxation characteristics of the palm. We conducted relaxation tests on 11 young adults (6 males, 5 females, 18 < age < 30, mean age: 25 ± 4 yr) and 9 older adults (6 males, 3 females, age > 50, mean age: 61.5 ± 11.5 yr) using a 3 mm indenter to a depth of 50% of each participant's soft tissue thickness. The relaxation parameters of the QLV model were found to differ with age and sex, emphasizing the importance of using targeted material models to represent palmar soft tissue mechanics. Older adults showed on average 2.3-fold longer relaxation time constant compared to younger adults. It took 1.2-fold longer for young males to reach equilibrium than for young females; however, young females had a higher level of relaxation (36%) than young males (33%). Differences in specific QLV model parameters, P1, P2, and α were also found between age and sex groups. QLV characteristics differentiated by age and sex, add biofidelity to computational models which can provide a better representation of the diversity of tissue properties in the population.
手掌软组织的体内特征可用于提高人体模型的准确性，以探索和模拟一系列接触场景。组织特征有助于评估损伤预防策略，并设计依赖于量化物理接触的技术，如假肢、可穿戴设备和辅助设备。在本研究中，开发了一种简化的准线性粘弹性（QLV）模型，以量化手掌在体内的大变形软组织松弛特性。我们使用3毫米压头对11名年轻人（6名男性，5名女性，18＜年龄＜30，平均年龄：25±4岁）和9名老年人（6名男性，3名女性，年龄＞50，平均年龄：61.5±11.5岁）进行了松弛测试，压入深度为每个参与者软组织厚度的50%。发现QLV模型的松弛参数因年龄和性别而异，这强调了使用针对性材料模型来表示手掌软组织力学的重要性。与年轻人相比，老年人的平均松弛时间常数长2.3倍。年轻男性达到平衡的时间比年轻女性长1.2倍；然而，年轻女性的松弛程度（36%）高于年轻男性（33%）。在年龄和性别组之间还发现了特定QLV模型参数P1、P2和α的差异。按年龄和性别区分的QLV特征为计算模型增添了生物逼真度，从而可以更好地表示人群中组织特性的多样性。
