The University of Queensland, School of Human Movement and Nutrition Sciences, Centre for Sensorimotor Neuroscience, Brisbane, 4072, Queensland, Australia.
Sci Rep. 2017 Dec 20;7(1):17958. doi: 10.1038/s41598-017-17771-7.
During human walking, the tibialis posterior (TP) tendon absorbs energy in early stance as the subtalar joint (STJ) pronates. However, it remains unclear whether an increase in energy absorption between individuals, possibly a result of larger STJ pronation displacement, is fulfilled by greater magnitudes of TP tendon or muscle fascicle strain. By collecting direct measurements of muscle fascicle length (ultrasound), MTU length (3D motion capture and musculoskeletal modelling), and TP muscle activation (intramuscular electromyography) we endeavoured to illustrate that the TP tendinous tissue fulfils the requirements for energy absorption at the STJ as a result of an increase in muscle force production. While a significant relationship between TP tendon strain, energy absorption at the STJ (R = 0.53, P = < 0.01) and STJ pronation (R = 0.53, P = < 0.01) was evident, we failed to find any significant associations between tendon strain and surrogate measure of TP muscle force (TP muscle activation together with ankle and subtalar joint moments). These results suggest that TP tendon compliance may explain the variance in pronation and energy absorption at the STJ. Therefore, as the tendinous tissue of the TP is accountable for the absorption of energy at the STJ it may be predisposed to strain-induced injury.
在人类行走过程中，当距下关节（STJ）内翻时，胫骨后肌（TP）肌腱在早期站立时吸收能量。然而，目前尚不清楚个体之间能量吸收的增加是否是由于 STJ 更大的内翻位移引起的，这是否通过更大的 TP 肌腱或肌束应变来实现。通过直接测量肌束长度（超声）、MTU 长度（3D 运动捕捉和骨骼肌肉建模）和 TP 肌肉激活（肌内电描记法），我们努力说明由于肌肉力量产生的增加，TP 腱组织满足 STJ 能量吸收的要求。虽然 TP 肌腱应变与 STJ 处的能量吸收（R=0.53，P<0.01）和 STJ 内翻（R=0.53，P<0.01）之间存在显著关系，但我们未能发现肌腱应变与 TP 肌肉力量的替代测量值（TP 肌肉激活加上踝关节和距下关节力矩）之间存在任何显著关联。这些结果表明，TP 肌腱顺应性可能解释了 STJ 处的内翻和能量吸收的差异。因此，由于 TP 的腱组织负责 STJ 处的能量吸收，因此它可能容易受到应变诱导的损伤。
