Ankle and midtarsal joint quasi-stiffness during walking with added mass

PeerJ

Jeffrey M. Patterson¹  Nikolaos Papachatzis¹  Kota Z. Takahashi¹  Andrew M. Kern¹  Dustin A. Bruening² 

[1] Department of Biomechanics, University of Nebraska at Omaha, Omaha, NE, USA;Exercise Sciences Department, Brigham Young University, Provo, UT, USA;

关键词: Arch;    Locomotion;    Foot;    Biomechanics;    Windlass mechanism;    Midtarsal joint;   

DOI  :  10.7717/peerj.7487

来源: DOAJ

【 摘 要 】

Examination of how the ankle and midtarsal joints modulate stiffness in response to increased force demand will aid understanding of overall limb function and inform the development of bio-inspired assistive and robotic devices. The purpose of this study is to identify how ankle and midtarsal joint quasi-stiffness are affected by added body mass during over-ground walking. Healthy participants walked barefoot over-ground at 1.25 m/s wearing a weighted vest with 0%, 15% and 30% additional body mass. The effect of added mass was investigated on ankle and midtarsal joint range of motion (ROM), peak moment and quasi-stiffness. Joint quasi-stiffness was broken into two phases, dorsiflexion (DF) and plantarflexion (PF), representing approximately linear regions of their moment-angle curve. Added mass significantly increased ankle joint quasi-stiffness in DF (p < 0.001) and PF (p < 0.001), as well as midtarsal joint quasi-stiffness in DF (p < 0.006) and PF (p < 0.001). Notably, the midtarsal joint quasi-stiffness during DF was ~2.5 times higher than that of the ankle joint. The increase in midtarsal quasi-stiffness when walking with added mass could not be explained by the windlass mechanism, as the ROM of the metatarsophalangeal joints was not correlated with midtarsal joint quasi-stiffness (r = −0.142, p = 0.540). The likely source for the quasi-stiffness modulation may be from active foot muscles, however, future research is needed to confirm which anatomical structures (passive or active) contribute to the overall joint quasi-stiffness across locomotor tasks.

【 授权许可】

Unknown