Abstract
To comparatively investigate the morphological adaptation of the human foot for achieving robust and efficient bipedal locomotion, we develop three-dimensional finite element models of the human and chimpanzee feet. Foot bones and the outer surface of the foot are extracted from computer tomography images and meshed with tetrahedral elements. The ligaments and plantar fascia are represented by tension-only spring elements. The contacts between the bones and between the foot and ground are solved using frictionless and Coulomb friction contact algorithms, respectively. Physiologically realistic loading conditions of the feet during quiet bipedal standing are simulated. Our results indicate that the center of pressure (COP) is located more anteriorly in the human foot than in the chimpanzee foot, indicating a larger stability margin in bipedal posture in humans. Furthermore, the vertical free moment generated by the coupling motion of the calcaneus and tibia during axial loading is larger in the human foot, which can facilitate the compensation of the net yaw moment of the body around the COP during bipedal locomotion. Furthermore, the human foot can store elastic energy more effectively during axial loading for the effective generation of propulsive force in the late stance phase. This computational framework for a comparative investigation of the causal relationship among the morphology, kinematics, and kinetics of the foot may provide a better understanding regarding the functional significance of the morphological features of the human foot.
Highlights
To adapt to habitual bipedal locomotion, the human foot has evolved significantly in the course of human evolution (Morton, 1922; Weidenreich, 1923; Morton, 1924; Susman, 1983)
A 3D finite element (FE) model of the human and chimpanzee feet was developed to comparatively investigate the morphological adaptation of the human foot, which presumably adapted to efficient bipedal locomotion
This study demonstrated that the transmission of the axial load from the foot to the ground was markedly different between the human and chimpanzee foot models
Summary
To adapt to habitual bipedal locomotion, the human foot has evolved significantly in the course of human evolution (Morton, 1922; Weidenreich, 1923; Morton, 1924; Susman, 1983). The foot of nonhuman primates, such as chimpanzees, has an opposable hallux that faces the other four digits to allow the grasping of objects. Because human bipedal locomotion is a mechanical phenomenon that translates the body center-of-mass while avoiding a fall by the appropriate control of reaction forces applied to the body from the ground, the unique morphological specialization of the human foot is expected to be closely associated with the acquisition of habitual bipedal locomotion during the course of human evolution. The fact that the human foot is morphologically distinct from that of other primates indicates that the modification of the foot structure is vital to the evolution of human bipedal locomotion
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
