Identifying gender-related gait changes offers valuable insights into the role of gender in motor control. It is anticipated that more difficult gait tasks (obstacle crossing) may reveal gender-specific effects on gait parameters. The present study aimed to explore the gait adaptations of male and female participants when stepping over obstacles of 0 cm, 13 cm, 19 cm, and 26 cm in height. A total of 12 male and 12 female participants were recruited. The Vicon motion capture system and AMTI force plates were utilized to obtain the gait parameters. Moreover, spatiotemporal parameters were investigated. Two-way repeated ANOVA (gender * obstacle height) and three-way repeated ANOVA (gender * obstacle height * leg) were performed to compare gait parameters, respectively. Correlations between maximum joint angle and obstacle height were also evaluated. Significant interactions were observed for leading leg swing time, maximum hip extension angle, maximum knee flexion angle, and maximum ankle plantarflexion angle (gender * obstacle height). There were some differences in gait parameters between males and females in the unobstructed gait, and these changes became more evident as obstacle height increased. This study also identified significant differences in gait parameters between leading and trailing legs when stepping over the obstacle.

Custom-made insoles are designed to redistribute foot load and prevent potential pain. Common methods to investigate the effectiveness of insoles include finite element method and experimental approach. However, most finite element research has focused on the two-dimensional plantar fascia stresses during static standing with insoles, rather than those of three-dimensional plantar fascia. Furthermore, the effects of insole with design parameters (metatarsal pad, toe pad, and arch support) on dynamic plantar pressures still need further exploration. Therefore, this study aimed to quantify the impact of custom-made insoles on foot biomechanics by combining both methods. Finite element method was employed to evaluate stress on the plantar fascia and bony structures when static standing, both barefoot and with a custom-made insole. Furthermore, 10 participants were recruited to investigate dynamic plantar pressures during walking barefoot and with insole. The relative time of four subphases during stance phase, total contact time, peak plantar pressure (Peak P), and pressure time integral (PTI) were assessed. Finite element results revealed reduced plantar fascia stresses and more uniform stress distribution over metatarsals and phalanges when standing with insole. Additionally, Peak P and PTI values in the second and third metatarsals were significantly lower when walking with insole. With the presence of insole, Peak P and PTI values in medial regions were significantly reduced, except for the midfoot region. In conclusion, custom-made insole with the addition of a metatarsal pad, toe pad, and arch support can effectively distribute foot tissue stress evenly, alleviate plantar pressure, and thus prevent pain. © IMechE 2025.

目的随着人口老龄化进程的日益加剧,由退行性疾病、不恰当运动方式以及骨关节病变等原因造成的骨软骨损伤病变的发生率在不断上升。介于骨软骨结构的复杂性和关节软骨自身缺少神经和血管,目前,临床上针对骨软骨损伤尚未有理想的治疗方式

Due to the limited self-healing ability of cartilage, cartilage defect repair remains a challenge in clinical treatment. Therefore, there is a need to provide patients with a promising cartilage defect repair strategy. In this study, we have reported an icariin-loaded PVA based biocompatible hydrogel scaffold for cartilage defect repair. The PTGH+Icariin hydrogel was prepared by a simple physical cross-linking method and consisted of polyvinyl alcohol (PVA), tannic acid (TA), gelatin (Gel), hyaluronic acid (HA) and icariin. Inspired by the natural cartilage matrix compositions, the Gel and HA were used to improve the bioactivity and biocompatibility of hydrogel. Furthermore, icariin was introduced to further enhance the hydrogel's ability for cartilage regeneration. The results showed that PTGH+icariin hydrogel exhibited porous microstructures and tough mechanical properties. In vitro cell experiments confirmed PTGH+Icariin hydrogels could promote chondrocytes proliferation, chondrocytes spreading and chondrocytes migration. Meanwhile, the PTGH+Icariin hydrogel demonstrated the ability to promote the cartilage regeneration in a rat cartilage defect model. In particular, the implantation of PTGH+Icariin hydrogel could facilitate the restoration of motor function in rats. This study will provide a potential approach for the treatment of cartilage defects. © 2024 The Authors

Poly(vinyl alcohol) (PVA) hydrogels exhibit great potential as ideal biomaterials for tissue engineering, owing to their non-toxicity, high water content, and strong biocompatibility. However, limited mechanical strength and low bioactivity have constrained their application in bone tissue engineering. In this study, we have developed a tough PVA-based hydrogel using a facile physical crosslinking method, comprising of PVA, tannic acid (TA), and hydroxyapatite (HA). Systematic experiments were conducted to examine the physicochemical properties of PVA/HA/TA hydrogels, including their compositions, microstructures, and mechanical and rheological properties. The results demonstrated that the PVA/HA/TA hydrogels possessed the porous microstructures and excellent mechanical properties. Furthermore, collagen type I (Col-I) was used to further improve the biocompatibility and bioactivity of PVA/HA/TA hydrogels. In vitro experiments revealed that PVA/HA/TA/COL hydrogel could offer a suitable microenvironment for the growth of MC3T3-E1 cells and promote their osteogenic differentiation. Meanwhile, the PVA/HA/TA/COL hydrogel demonstrated the ability to promote bone regeneration and osteointegration in a rat femoral defect model. This study provides a potential strategy for the use of PVA-based hydrogels in bone tissue engineering.

In this study, novel silk fibroin@Ag spheres were synthesized by in situ growth of Ag nanoparticles (NPs) on silk fibroin (SF) spheres and their microstructure, in vitro biocompatibility, and antibacterial property were evaluated. SEM observation showed that SF@Ag spheres had a spherical morphology with a diameter of 1–10 µm. TEM observation revealed that each SF@Ag sphere had a dense structure and its surface was deposited with Ag NPs with a diameter of 10–50 nm. In vitro biocompatibility evaluation indicated that SF@Ag spheres were not cytotoxic when incubated with osteoblast MC3T3-E1 cells. Moreover, when exposed to two representative types of gram-negative Escherichia coli and gram-positive Staphylococcus aureus, SF@Ag spheres showed a good antibacterial property against the growth of both types of bacteria. © 2023 Elsevier B.V.

Lateral wedge insole (LWI) is a frequently recommended treatment option for early and midterm stages of medial knee osteoarthritis. However, studies of its effects on the lower limb joints are incomplete and imperfect. The main purpose of this study was to quantitatively analyze the response of intervention of LWI on lower-limb joint kinematics, ground reaction forces (GRFs), and centre of pressure (COP). Gait analysis of 16 healthy subjects was conducted. Three-dimensional motion data and force plate measurements were collected in the control (barefoot) and experimental conditions (wearing a pair of assigned shoes with 0, 7, and 10mm LWIs). Results showed that the peak knee flexion angle was increased by 3.43°, 3.09°, and 3.27° with 0, 7, and 10mm LWIs, respectively (p<0.01). The ankle peak dorsiflexion angle was significantly decreased by 3.79°, 2.19°, and 1.66° with 0, 7, and 10mm LWIs, respectively (p=0.02). The internal rotation angle was increased by 2.78°, 3.76°, and 4.58° with 0, 7, and 10mm LWIs, respectively (p<0.01). The forefoot with LWIs showed highly significantly smaller inversion, eversion, and adduction angles (all p<0.01). The 1st peak of the vertical GRF (p=0.016) also increased significantly by a maximum of 0.06 body weight (BW) with LWIs. These results indicated that biomechanical changes and limitations of lateral wedges insole should be analyzed in more detail, possibly leading to new guidelines for the design and application. © 2024. The Author(s).

背景:关于脊柱后凸的生物力学研究大多集中在躯干肌肉力量以及矢状面平衡等方面,关于脊柱后凸过程中脊柱内部的生物力学响应鲜有报道。目的:通过模拟姿势性脊柱后凸过程,探究姿势性脊柱后凸过程中脊柱的生物力学响应。方法:建立正常人

3D printing has been widely applied for preparing artificial blood vessels, which will bring innovation to cardiovascular disorder intervention. However, the printing resolution and anti-infection properties of small-diameter vessels (phi < 6 mm) have been challenging in 3D printing. The primary objective of this research is to design a novel coaxial 3D-printing postprocessing method for preparing small-size blood vessels with improved antibacterial and angiogenesis properties. The coaxial printing resolution can be more conveniently improved. Negatively charged polyvinyl alcohol (PVA) and alginate (Alg) interpenetrating networks artificial vessels are immersed in positively charged chitosan (CTS) solution. Rapid dimensional shrinkage takes place on its outer surface through electrostatic interactions. The maximum shrinkage size of wall thickness can reach 61.2%. The vessels demonstrate strong antibacterial properties against Escherichia coli (98.8 +/- 0.5%) and Staphylococcus aureus (97.6 +/- 1.4%). In rat dorsal skin grafting experiments, Cu2+ can promote angiogenesis by regulating hypoxia-inducible factor-1 pathway. No artificial blood vessel blockage occurs after 5 days of blood circulation in vitro.

The acidity of high tannic acid (TA) content solution can destroy the structure of protein, such as gelatin (G). This causes a big challenge to introduce abundant TA into the G-based hydrogels. Here, the G-based hydrogel system with abundant TA as hydrogen bonds provider was constructed by a "protective film" strategy. The protective film around the composite hydrogel was first formed by the chelation of sodium alginate (SA) and Ca2+. Subsequently, abundant TA and Ca2+ were successively introduced into the hydrogel system by immersing method. This strategy effectively protected the structure of the designed hydrogel. After treatment with 0.3 w/v TA and 0.06 w/v Ca2+ solutions, the tensile modulus, elongation at break and toughness of G/SA hydrogel increased about 4-, 2-, and 6-fold, respectively. Besides, G/SA-TA/Ca2+ hydrogels exhibited good water retention, anti-freezing, antioxidant, antibacterial properties and low hemolysis ratio. Cell experiments showed that G/SA-TA/Ca2+ hydrogels possessed good biocompatibility and could promote cell migration. Therefore, G/SA-TA/Ca2+ hydrogels are expected to be used in the field of biomedical engineering. The strategy proposed in this work also provides a new idea for improving the properties of other protein-based hydrogels. © 2023