The effects of Achilles tendon compliance on triceps surae mechanics and energetics in walking

JOURNAL OF BIOMECHANICS

卷:60

Article

Orselli, Maria Isabel V.^1,2  Franz, Jason R.^3,4  Thelen, Darryl G.^5,6,7 

[1] Univ Sao Paulo, Phys Inst, Sao Paulo, Brazil

[2] Franciscan Univ, Biomed Engn Course, Rio Grande Do Sul, Brazil

[3] Univ North Carolina Chapel Hill, Joint Dept Biomed Engn, Chapel Hill, NC USA

[4] North Carolina State Univ, Chapel Hill, NC USA

[5] Univ Wisconsin, Dept Mech Engn, Madison, WI 53706 USA

[6] Univ Wisconsin, Dept Biomed Engn, Madison, WI USA

[7] Univ Wisconsin, Dept Orthoped & Rehabil, Madison, WI USA

关键词: Plantarflexor;    Musculoskeletal modeling;    Forward dynamics;    Mechanical power;    Metabolic energy;   

DOI  :  10.1016/j.jbiomech.2017.06.022

来源: Elsevier

【 摘 要 】

Achilles tendon (AT) compliance can affect the generation and transmission of triceps surae muscle forces, and thus has important biomechanical consequences for walking performance. However, the uniarticular soleus (SOL) and the biarticular (GAS) function differently during walking, with in vivo evidence suggesting that their associated fascicles and tendinous structures exhibit unique kinematics during walking. Given the strong association between muscle fiber length, velocity and force production, we conjectured that SOL and GAS mechanics and energetic behavior would respond differently to altered AT compliance. To test this, we characterized GAS and SOL muscle and tendon mechanics and energetics due to systematic changes in tendon compliance using musculoskeletal simulations of walking. Increased tendon compliance enlarged GAS and SOL tendon excursions, shortened fiber operation lengths and affected muscle excitation patterns. For both muscles, an optimal tendon compliance (tendon strains of approximately 5% with maximum isometric force) existed that minimized metabolic energy consumption. However, GAS muscle-tendon mechanics and energetics were significantly more sensitive to changes in tendon compliance than were those for SOL. In addition, GAS was not able to return stored tendon energy during push-off as effectively as SOL, particularly for larger values of tendon compliance. These fundamental differences between GAS and SOL sensitivity to altered tendon compliance seem to arise from the biarticular nature of GAS. These insights are potentially important for understanding the functional consequences of altered Achilles tendon compliance due to aging, injury, or disease. (C) 2017 Elsevier Ltd. All rights reserved.

【 授权许可】

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