The Impact of Locomotor Speed on the Human Metatarsophalangeal Joint Kinematics

Kunyang Wang; Sivangi Raychoudhury; Dan Hu; Lei Ren; Jing Liu; Haohua Xiu; Wei Liang; Bingqian Li; Guowu Wei; Zhihui Qian

doi:10.3389/fbioe.2021.644582

The Impact of Locomotor Speed on the Human Metatarsophalangeal Joint Kinematics

Front Bioeng Biotechnol. 2021 Apr 20:9:644582. doi: 10.3389/fbioe.2021.644582. eCollection 2021.

Authors

Kunyang Wang^{1

2}, Sivangi Raychoudhury², Dan Hu², Lei Ren^{1

2}, Jing Liu¹, Haohua Xiu¹, Wei Liang¹, Bingqian Li¹, Guowu Wei³, Zhihui Qian¹

Affiliations

¹ Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun, China.
² School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester, United Kingdom.
³ School of Science, Engineering and Environment, University of Salford, Salford, United Kingdom.

Abstract

This paper aims to further our previous study to investigate the effect of speed on the human metatarsophalangeal (MP) joint kinematics during running on level ground. The 3D motion of the foot segments was captured by a twelve-camera motion analysis system, and the ground reaction forces and moments were recorded by using a six-force plate array. The relative movement between the tarsometatarsi (hindfoot) and phalanges (forefoot) segments were recorded to obtain the 3D orientation and position of the functional axis (FA) of the MP joint. The results show that the FA locates about an average of 19% foot length (FL) anterior to the anatomical axis (AA) across all running speeds, and is also 4.8% FL inferior to the AA during normal and fast run. Similar to walking, the functional axis is more oblique than the anatomical axis with a more anterior-inferior orientation across all the running speeds. This suggests that representing MP joint with the AA may mislead the calculation of joint moment/power and muscle moment arms in both running and walking gait. Compared with previous study, we found that walking and running speeds have statistically significant effects on the position of the FA. The functional axis moves frontward to a more anterior position when the speed increases during walking and running. It transfers upward in the superior direction with increasing speed of walking, but moves more toward the inferior position when the velocity increased further to running. Also, the orientation of FA in sagittal plane became more oblique toward the vertical direction as the speed increased. This may help in moderating the muscular effort, increase the muscle EMA and improve the locomotor performance. These results would contribute to understanding the in vivo biomechanical function of the MP joint and also the foot propulsion during human locomotion.

Keywords: functional axis; human locomotion; metatarsophalangeal joint; position and orientation; three-dimensional kinematics.