In Situ Low Load Mechanical Behavior of Skeletal Muscle: An Improved Understanding of Injury and Healing

0201783最佳在此研究者发起的奖项下，将进行研究，以提高对骨骼肌基本生物力学及其对拉伸损伤和愈合的机械响应的理解。特别是，拉伸速度和刺激对正常肌肉行为的影响，以及肌肉从偏心拉伸损伤中恢复的影响将被讨论。骨骼肌是一种表现出非线性粘弹性行为的复杂材料。单轴拉伸的力学响应开始于非线性应变硬化或脚趾向内行为，然后是线性响应，最终材料在破坏之前软化。在健康和拉伸损伤的骨骼肌中，将在兔的胫骨前肌中检测对拉伸速率和刺激状态变化的敏感性。PIS新的唯象肌肉模型由一个非线性麦克斯韦流体元件、一个收缩元件和一个刺激诱导的线性弹簧组成，该模型已经证明可以解释上面概述的机械响应，并结合精心设计的统计设计，将用于解释实验的载荷-位移数据。研究结果有可能影响骨骼肌损伤的治疗计划。

0201783BestUnder this Investigator Initiated Award, studies will be performed that will improve understanding of the fundamental biomechanics of skeletal muscle and its mechanical response to stretch injury and healing. In particular, the stretch rate and stimulation effects on normal muscle behavior, and that of muscle recovering from eccentric stretch injury will be addressed. Skeletal muscle is a complex material that exhibits nonlinear viscoelastic behavior. Mechanical response to uniaxial stretch begins with nonlinear strain-stiffening, or toe-in behavior, followed by a linear response, and ultimately material softening prior to failure. Sensitivity to stretch rate and stimulation state variations, in both healthy and stretch-injured skeletal muscles, will be examined in vivo in rabbit Tibialis Anterior muscles. The PIs new phenomenological muscle model consisting of a nonlinear Maxwell fluid element combined in parallel with a contractile element and a stimulation induced linear spring, already demonstrated to explain the mechanical response outlined above, in conjunction with a carefully planned statistical design, will be used to interpret the experimental load-displacement data. Results of the studies have the potential of influencing treatment plans for skeletal muscle injuries.