Effects of Artificial Texture Insoles and Foot Arches on Improving Arch Collapse in Flat Feet

Biomechanical variations in patients with flatfoot deformity: Impact of gender, age, and BMI on foot kinetics and kinematics

Background

Flatfoot is considered by the collapse of the foot arch, altered biomechanics and impacting functional abilities. The biomechanical gait alteration of foot kinematics and kinetics in individuals with flatfoot, based on gender, age and Body mass index (BMI) in each cohort is unclear. This study explores how gender, age, and body mass index (BMI) impact distinct foot biomechanical characteristics, including ankle joint angle (Jc°), Ground force reaction angle (GFR°), Achilles tendon force (T), Ankle joint force (Jc) and vertical ground reaction force (VGRF) during the gait stance phase, in flatfoot versus normal-foot individuals on Indian Population.

Method

A foot pressure test and sagittal plane motion analysis were performed on 142 individuals with normal-foot arches and 102 with flatfoot, stratified by gender, age, and BMI. Calculations of the magnitude and direction of forces in ankle joint equilibrants relied on inverse dynamic analysis, vertical ground force reaction and mapping motion data of the gait stance phases.

Result

In the midstance phase, females with high BMI (HBMI) in the middle and older age group (p = 0.029 and p = 0.014), and males with HBMI in the older age group (p = 0.039) demonstrate significantly higher V G R F . Females and males with HBMI in middle and older age groups, along with males with normal BMI in the older age cohort, show positive and negative ranges of GFR°, indicating gait instability. In the push-off phase, females with HBMI in a middle-aged group exhibit significantly lower T a n d J c (p = 0.023 and p = 0.026) respectively.

Conclusion

The biomechanical issues in individuals with flatfoot, while accounting for the influence of gender, age and BMI, are crucial for tailored interventions and precise solutions to biomechanical issues, thereby enhancing foot function and reducing discomfort.

Physicians' experiences with indications and prescriptions of foot orthoses-A cross-sectional study in northern Germany

Background

Foot orthoses (FOs) are prescribed by general practitioners (GPs) and orthopedic surgeons for various complaints. As there are very limited medical guidelines and checklists, the prescription of FOs is often inconsistent. Therefore, our study to evaluate the general prescription behavior and indication experiences with FOs from the perspective of GPs and orthopedists.

Methods

A survey was carried out using a questionnaire from October to December 2021. GPs and orthopedic surgeons in northern Germany were included. The focus of the survey was to examine which foot problems would lead GPs and orthopedic surgeons to prescribe FOs and to evaluate what factors these physicians included in their diagnostic analysis. Apart from descriptive analyses, a stepwise linear regression analysis was performed to explore potential associations of the primary outcome variable 'specific effect on the prescription of FOs', which was introduced to shed light upon the estimated added value of the prescription of FOs.

Results

Out of the 790 questionnaires distributed, 184 questionnaires were returned by GPs (n = 95) and orthopedic surgeons (n = 74) (response rate 23 %). FOs were most frequently prescribed for talipes valgus (96 %) and heel spur (54 %). Diagnostic analysis was mainly carried out clinically. Custom-made FOs (82 %) were prescribed more frequently than prefabricated FOs (6 %). Regular interaction within the prescription process was most commonly with orthopedic technicians (61 %). The estimation of the specific effect on FO prescription was assessed by a mean of 66 % of the participants, 82 % recommended self-exercises as an additional therapy.

Conclusions

FOs are a specific and well-established aid prescribed by many GPs and orthopedic surgeons for a variety of foot complaints. Despite being one of the most frequently prescribed orthopedic devices, the utilization of FOs is predominantly explorative due to a growing but nevertheless still deficient body of well-researched evidence. There is a clear need for a uniform approach to the indication and prescription of FOs among physicians.

Improvement of Mechanical Properties of Personalized Insole Manufactured with Selective Laser Sintering Based on Process Parameter Optimization and Cell Structure Design

Personalized insoles manufactured with selective laser sintering (SLS) technology are popular especially for exercisers and patients with foot diseases. However, insufficient strength and toughness of personalized insoles would result in crack and even fracture. To address these deficiencies and fill the research shortages in this area, optimization of process parameters and design of cell structures are conducted to improve the mechanical performance of insoles in this topic. First, six sets of process parameters in terms of energy density were designed for parameter optimization. The energy density of 0.08 J/mm2 was affirmed to be the finest selection. Then, specific cell structures featuring both whale shark and ancient soldier armor (WS structures for short) with various curvature radius were established to act on the bottom of the insole to further strengthen the personalized insoles. It was shown that the WS14 structure exhibited the best performance characteristics. Finally, a personalized insole with the array of WS14 structures was developed with SLS under the optimum energy density of 0.08 J/mm2. Finite element method analysis and exercising testing were performed to evaluate the insole performance. The result reveals that a more uniform stress distribution is attained of the WS14 personalized insole, and the fracture problem is indeed solved.

Effects of textured insoles and elastic braces on dynamic stability in patients with functional ankle instability

BACKGROUND

Functional ankle instability (FAI) is a common condition that affects individuals who have experienced previous ankle sprains. Textured insoles and elastic ankle braces have been previously used as interventions to improve stability in FAI patients. However, the optimal combination of these interventions has not been fully explored. The objective of this study was to investigate the effects of different types of textured insoles and elastic ankle braces on the dynamic stability of individuals diagnosed with FAI.

METHODS

The study involved 18 FAI patients who performed single-leg landing tasks with and without wearing an eight-band elastic ankle brace while wearing textured insoles with protrusion heights of 0 mm, 1 mm, and 2 mm. The dynamic posture stability index (DPSI) and its components in the anterior-posterior (APSI), mediolateral (MLSI) and vertical (VSI) directions were calculated from the ground reaction force collected from the Kistler force plate during the first three seconds of the landing tasks.

RESULTS

A significant interaction was found between textured insole type and ankle brace for DPSI (P = 0.026), APSI (P = 0.001), and VSI (P = 0.021). However, no significant interaction was observed for MLSI (P = 0.555). With elastic ankle braces, textured insoles with 1-mm protrusions significantly enhanced anterior-posterior, mediolateral, vertical, and overall stability compared to textured insoles with no and 2 mm protrusions (P < 0.05). Without elastic ankle braces, textured insoles with 1-mm protrusions significantly improved the anterior-posterior (P = 0.012) and overall stability (P = 0.014) of FAI patients compared to smooth insoles.

CONCLUSIONS

The combination of textured insoles with 1-mm protrusion heights and an elastic ankle brace could enhance the dynamic stability of individuals with FAI, potentially mitigating the risk of ankle sprains.

Morphology and Mechanical Properties of Plantar Fascia in Flexible Flatfoot: A Noninvasive In Vivo Study

Plantar fascia plays an important role in human foot biomechanics; however, the morphology and mechanical properties of plantar fascia in patients with flexible flatfoot are unknown. In this study, 15 flexible flatfeet were studied, each plantar fascia was divided into 12 positions, and the morphologies and mechanical properties in the 12 positions were measured in vivo with B-mode ultrasound and shear wave elastography (SWE). Peak pressures under the first to fifth metatarsal heads (MH) were measured with FreeStep. Statistical analysis included 95% confidence interval, intragroup correlation coefficient (ICC_1,1), one-way analysis of variance (one-way ANOVA), and least significant difference. The results showed that thickness and Young's modulus of plantar fascia were the largest at the proximal fascia (PF) and decreased gradually from the proximal end to the distal end. Among the five distal branches (DB) of the fascia, the thickness and Young's modulus of the second and third DB were larger. The peak pressures were also higher under the second and third MH. This study found a gradient distribution in that the thickness and Young's modulus gradient decreased from the proximal end to the distal end of plantar fascia in the longitudinal arch of flexible flatfeet. In the transverse arch, the thickness and Young's modulus under the second and third DB were larger than those under the other three DB in flexible flatfoot, and the peak pressures under the second and third MH were also larger than those under the other three MH in patients with flexible flatfoot. These findings deepen our understanding of the changes of biomechanical properties and may be meaningful for the study of pathological mechanisms and therapy for flexible flatfoot.