China 
Africa 
Explore chapters and articles related to this topic
POFBG Sensor Applications
Published in Ricardo Oliveira, Lúcia Bilro, Rogério Nogueira, Polymer Optical Fiber Bragg Gratings, 2019
Ricardo Oliveira, Lúcia Bilro, Rogério Nogueira
The use of embedded POFBGs for biomedical applications has already been demonstrated for the monitoring of the foot plantar pressure in dynamic gait [44]. For that, the authors used a 10 mm cork insole grooved with a 2.5 mm deep and 2 mm wide across key areas for foot plantar pressure namely heel, midfoot, metatarsal, and toe. These specific areas were further caved in circular shapes with a diameter of 10 mm and a depth of 5 mm. A POFBG array with FBG separation length pre-selected to fall within the middle region of those areas was then inserted and filled with an epoxy resin. Each POFBG was able to shift the Bragg peak wavelength accordingly to the pressure-induced strain and thus, capable to monitor the foot plantar pressure. Results revealed similar performance to the ones fabricated for the same system using silica FBGs [49]. However, the sensitivity was doubled and the benefits of high flexibility and non-brittle nature of POFs is more appealing.
Effects of Elastic Shoe Cover on Running Mechanics
Published in Youlian Hong, Routledge Handbook of Ergonomics in Sport and Exercise, 2013
Youlian Hong, Lin Wang, Jing Xian Li
In analysing plantar loading, the insole was divided and masked into nine areas according to the human foot anatomy: M1 (medial heel), M2 (lateral heel), M3 (medial midfoot), M4 (lateral midfoot), M5 (first metatarsal head), M6 (second metatarsal head), M7 (third, fourth and fifth metatarsal heads), M8 (great toe) and M9 (lesser toes), as seen in Figure 27.3. Similar masks have been used in previous studies (Bontrager et al., 1997; Burnfield et al., 2004; Mao et al., 2006). Using the Novel Pedar software, parameters such as peak pressure in each mask, contact area in each mask, support time of the foot in each stance phase and the percentage of the contact time of each mask in relation to the total contact time of the foot were determined.
Biomechanical modelling and simulation of foot and ankle
Published in Youlian Hong, Roger Bartlett, Routledge Handbook of Biomechanics and Human Movement Science, 2008
In 1997, Lemmon et al.32 developed a 2D model of the second metatarsal bone and encapsulated soft tissue to investigate the metatarsal head pressure as a function of six insole thicknesses and two tissue thicknesses. The plantar soft tissue, polyurethane insole, and cloud crepe foamed midsole were defined as hyperelastic. Frictional contact between the foot and support was considered and a vertical load was applied at the metatarsal bone to simulate push-off. Orthosis with relatively soft material was found to reduce peak plantar pressure, which also decreased with an increase in insole thickness. The pressure reduction for a given increase of insole thickness was greater when plantar tissue layer was thinner. Using the same model, Erdemir et al.17 investigated 36 plug designs of a Microcell Puff midsole including a combination of three materials (Microcell Puff Lite, Plastazote medium, Poron), six geometries (straight or tapered with different sizes), and two locations of placement. Plugs that were placed according to the most pressurized area were more effective in plantar pressure reduction than those positioned based on the bony prominences. Large plugs (40 mm width) made of Microcell Puff Lite or Plastazote Medium, placed at peak pressure sites, provided the largest peak pressure reductions of up to 28 per cent.
Fifth metatarsal strain distribution during cutting motions in soccer
Published in Sports Biomechanics, 2023
Yusuke Miyazaki, Rui Sugizaki, Miku Kawasaki, Takumi Nakagawa, Yasuaki Saho, Tomohiko Tateishi
Simulations of the cadaveric bending tests were performed to validate the bending deformation of the fifth metatarsal model (Trabelsi et al., 2014). Similar to the cadaver’s bending test conducted by Trabelsi et al., these simulations constrained the displacement of nodes in the proximal part of the fifth metatarsal finite-element model. After selecting a node at the distal end, a bending load was applied in the vertically upward direction. The proximal and distal strains measured in the cadaver experiment were at SG1 and SG2, respectively, as shown in Figure 4(a). Figure 4(b) shows the strains obtained from the experimental results and simulations at the positions of SG1 and SG2. As because the experiment focused on the first and second metatarsal bones, the results cannot be compared with those of the fifth metatarsal finite-element model. The minimum diameters of the first and second metatarsal bones used in the experiment were 14.2 ± 0.424 mm and 8.76 ± 0.677 mm, respectively. In contrast, the minimum diameter of the fifth metatarsal finite-element model used in the simulation was 10.3 mm. Thus, we assumed that the strain decreases in the order of the second metatarsal bone, the fifth metatarsal bone, and the first metatarsal bone. As shown in Figure 4(b), the strain on the fifth metatarsal finite-element model was larger than that on the second metatarsal bone and smaller than that on the first metatarsal bone, as expected.
A new small-sized penguin from the late Eocene of Seymour Island with additional material of Mesetaornis polaris
Published in GFF, 2021
Piotr Jadwiszczak, Marcelo Reguero, Thomas Mörs
The micro-CT scanning revealed that the compact (cortical) and trabecular bone tissues left relatively little room for significant volumes of hollow spaces accounting for metatarsal medullary cavities (Fig. 3M–T). However, they can be observed along the distal second metatarsal, the distal two thirds of the fourth metatarsal, and, as several separate air spaces of highly diverse sizes, in the third metatarsal. The largest continuous empty volume appears to be inside the fourth metatarsal bone. The medullary cavity of the third tarsometatarsal, together with the associated trabecular bone, are characterized by a large content of some hyperdense material (Fig. 3M–P, R–T). This material has also spread into the trochlea, penetrating much of its dense spongy-bone meshwork (Fig. 3O, P, T). Trabecular bone within the proximal tarsometatarsus (the tarsal part and adjacent fragments of metatarsals) is devoid of such an infill/coating (Fig. 3O, P, Q). The tarsal/metatarsal transition zone is clearly visible (Fig. 3M, O, P).
Biomechanical factors affecting energy cost during running utilising different slopes
Published in Journal of Sports Sciences, 2020
Keitaro Seki, Heikki Kyröläinen, Kanami Sugimoto, Yasushi Enomoto
The two-dimensional coordinates in the sagittal plane were smoothed using a Butterworth low-pass digital filter at 10 Hz. Ground contact phase was detected based on the distance between the belt surface of the treadmill and following three markers: toe, fifth metatarsal bone, and heel. A rigid-body model consisting of 15 body segments (head, upper part of torso, lower part of torso, hand, forearm, upper arm, foot, shank, and thigh) was constructed using two-dimensional coordinates of anatomical landmarks. We focused on the sagittal plane because vertical movement can be analysed in the sagittal plane. The mass and centre of mass location of each segment were estimated by the coefficients of Ae, Tang, & Yokoi (1992). Then, body’s centre of mass location (CoM) was obtained as a resultant centre of mass of all body segments. The vertical displacement was defined as a difference between the lowest height of the CoM during the support phase and highest height during following flight phase. The external work (Wtotal) during ground contact was calculated using Equations (1)–(3) (Keir, Zory, Boudreau-Lariviere, & Serresse, 2012).