Effect of using a kinetic wedge during the hallux dorsiflexion resistance test in asymptomatic individuals.

BACKGROUND: The hallux dorsiflexion resistance test is a frequently employed clinical maneuver for assessing the initiation of the windlass mechanism This maneuver involves dorsiflexion of the phalanx of the hallux, thereby evaluating plantarflexion of the first metatarsal, elevation of the medial longitudinal arch, and supination of the rearfoot. The windlass mechanism plays a crucial role in gait, and orthopedic devices, such as a kinetic wedge, which aims to facilitate its activation by increasing the hallux dorsiflexion. Although it is believed that facilitating the windlass mechanism with the kinetic wedge should be directly correlated with a decrease in hallux dorsiflexion resistance, its effects have yet to be characterized. Thus, this study aimed to determine the influence of a kinetic wedge on hallux dorsiflexion resistance in asymptomatic individuals. METHODS: The sample comprised thirty participants (14 women and 16 men). A digital force gauge measured the force required to perform the hallux dorsiflexion resistance test during two conditions: barefoot and with a kinetic wedge. The Wilcoxon signed-rank test was used to compare the hallux dorsiflexion resistance between conditions. RESULTS: A statistically significant reduction in force (10.54 ± 3.16N vs. 19.62 ± 5.18N, p < 0.001) was observed when using the kinetic wedge compared to the barefoot condition during the hallux dorsiflexion resistance test. CONCLUSION: The use of a kinetic wedge reduces the required force for performing the passive hallux dorsiflexion resistance test in asymptomatic individuals. Future studies should determine to what extent the kinetic wedge can attenuate the required force to dorsiflex the hallux in individuals with musculoskeletal disorders such as plantar fasciopathy and functional hallux limitus.

Childhood obesity and its impact on the characteristics of gait stance phases: a cross-sectional study.

This study aimed to investigate the variations in foot type, laxity, dynamic characteristics of gait, and the characteristics of the stance phase of gait, in relation to body mass index (BMI) and groups of children of different ages. Additionally, it aimed to explore the correlations between BMI and these variables across children groups of different ages. A cross-sectional study was conducted involving 196 infants aged between 5 and 10 years old. The variables assessed included BMI, foot type, laxity, dynamic variables, and characteristics of the stance phase of gait. Significant variations were observed in foot type, laxity, certain dynamic variables, and characteristics of the stance phase of gait between normoweight (NW) and overweight/obese (OW/OB) groups among children aged between 5 and 10 years old (p ranged between 0.019 and 0.050). Moreover, BMI was also positively associated with the initial forefoot contact, heel off, total duration of the step, and forefoot contact phase of children 7 to 10 years of age (p ranged between < 0.010 and 0.040).   Conclusion: Children who are OW/OB had alterations at different stages of gait. Being OW/OB is related to alterations of the phases of gait mainly from 7 to 10 years of age, and spending more time in each of the phases of walking. This could indicate that children who are OW/OB, in addition to walking slower, overload the musculoskeletal system, subjecting their joints and muscles to greater stress. What is Known: • Children who are overweight (OW) and obese (OB) can experience changes in their musculoskeletal systems, posture, and gait due to increased body mass index. • OW and OB children experience additional stress on their musculoskeletal systems, impacting posture, biomechanics, mobility, physical activity, and daily tasks. Excessive plantar loading is linked to foot pain in adults. What is New: • Body mass index was positively associated with initial forefoot contact, heel off, total duration of the step, and forefoot contact phase in children aged 7 to 10 years old. OW/OB children aged 5-6 exhibited less ankle dorsiflexion and smaller relaxed calcaneal stance position (RCSP) as compared to normal-weight children. • Obese children aged 5-6 showed less pronation excursion, suggesting altered frontal plane movement due to RCSP differences. Children aged 7-8 who are OW/OB spent more time in certain gait phases, particularly in the forefoot contact phase. Being OW/OB is linked to altered gait parameters such as initial forefoot, heel off, total step duration, and forefoot contact phase. Being OW/OB was associated with a longer forefoot contact phase, particularly in the right foot.

The resting calcaneal stance position (RCSP): an old dog, with new tricks.

The objective of this study was to establish the accuracy of the resting calcaneal stance position (RCSP) for the assessment of flat foot (FF) in children, aligned to the validity of the foot posture index (FPI). The RCSP cut-off point was explored, in context of both FF prevalence and the relationship between FF and body weight. A total of 205 healthy children, aged 5 to 10 years, participated in a cross-sectional study. Correlation was performed between RCSP and FPI. ROC curve technique was calculated to assess differentiation between groups. A score equal to or greater than 7 on the FPI was used as the 'gold standard' for analysis. The correlation between FPI and RCSP was significant (r = 0.63; p < 0.01). The discrimination score on the ROC curve (6 points/degrees) shows that the model can be used to identify FF through RCSP, with a sensitivity of 67% and specificity of 85% returned.  Conclusion: The results of this study indicate the role of RCSP for simple, accessible and quick screening of paediatric FF. This is especially pertinent for non-podiatric healthcare professional without specialised paediatric foot knowledge. What is Known: • Most children develop a normal arch quickly, and flat feet usually resolve on their own between 2 and 6 years of age. • The measurement used to diagnose flat foot in children must be accurate, consistent, and valid to characterize the standard foot position. The Resting Calcaneal Stance Position (RCSP) is another widely used measure to evaluate the position of the flat foot in children. What is New: • The RCSP cut-off point 6 shows a sensitivity of 67% and a specificity of 85% thanks to the FPI as the Gold standard. • The RCSP is useful for health professionals who are not specialised in pediatric foot health. The RCSP is useful to detect flat foot in children.

Effects of Low-Dye Tape on Arch Height and Its Impact on the Medial Gastrocnemius Electromyographic Activity in Structurally Differentiable Foot Types: A Cross-Sectional Observational Study.

BACKGROUND: Low-Dye tape (LDT) is a short-term treatment for plantar fasciitis, where external stabilization by means of the tape improves kinetics, kinematics, pain level, and electromyography (EMG). PURPOSE: The purpose of this study was to compare the EMG of the medial gastrocnemius (MG) and changes in arch height (AH) based on the type of foot. METHODS: A total of 30 subjects participated in this study; they walked on a treadmill barefoot and when taped, where the average activity and changes in AH were measured over a 30 s period. The statistical intraclass correlation coefficient (ICC) to test for reliability was calculated, and the Wilcoxon test was determined for measures of EMG and AH. RESULTS: The reliability of the values of EMG was almost perfect. The data show that there was an increase in height in the comparison of the moment pre-baseline walking and post-taped walking on neutral feet (5.61 ± 0.46 vs. 5.77 ± 0.39 cm, p < 0.05), on pronated feet (5.67 ± 0.57 vs. 6.01 ± 0.53 cm, p < 0.001) and on supinated feet (5.97 ± 0.36 vs. 6.28 ± 0.27 cm, p < 0.05). In the MG, EMG activity decreased significantly in the taped condition compared to the baseline condition in neutral subjects (0.0081 ± 0.016 vs. 0.076 ± 0.016 mV, p < 0.05) and in pronated subjects (0.081 ± 0.022 vs. 0.068 ± 0.025 mV, p < 0.05). CONCLUSIONS: It was demonstrated that with the use of LDT, there was an improvement in the average activity in the MG in pronated and neutral feet. All foot types improved in arch height with the use of tape.

Overweight and Obesity: Its Impact on Foot Type, Flexibility, Foot Strength, Plantar Pressure and Stability in Children from 5 to 10 Years of Age: Descriptive Observational Study.

BACKGROUND: Overweight (OW) and childhood obesity (OB) may cause foot problems and affect one's ability to perform physical activities. The study aimed to analyze the differences in descriptive characteristics, foot type, laxity, foot strength, and baropodometric variables by body mass status and age groups in children and, secondly, to analyze the associations of the BMI with different physical variables by age groups in children. METHODS: A descriptive observational study involving 196 children aged 5-10 years was conducted. The variables used were: type of foot, flexibility, foot strength and baropodometric analysis of plantar pressures, and stability by pressure platform. RESULTS: Most of the foot strength variables showed significant differences between the normal weight (NW), OW and OB groups in children aged between 5 and 8. The OW and OB groups showed the highest level of foot strength. In addition, the linear regression analyses showed, in children aged 5 to 8 years, a positive association between BMI and foot strength (the higher the BMI, the greater the strength) and negative association between BMI and stability (lower BMI, greater instability). CONCLUSIONS: Children from 5 to 8 years of age with OW and OB show greater levels of foot strength, and OW and OB children from 7 to 8 years are more stable in terms of static stabilometrics. Furthermore, between 5 and 8 years, having OW and OB implies having more strength and static stability.

Changes in the Kinematics of Midfoot and Rearfoot Joints with the Use of Lateral Wedge Insoles.

The lateral wedge insole (LWI) is a typical orthopedic treatment for medial knee osteoarthritis pain, chronic ankle instability, and peroneal tendon disorders. It is still unknown what the effects are in the most important joints of the foot when using LWIs as a treatment for knee and ankle pathologies. Objectives: The aim of this study was to determine the influence of LWIs on the position of the midfoot and rearfoot joints by measuring the changes using a tracking device. Methods: The study was carried out with a total of 69 subjects. Movement measurements for the midfoot were made on the navicular bone, and for the rearfoot on the calcaneus bone. The Polhemus system was used, with two motion sensors fixed to each bone. Subjects were compared by having them use LWIs versus being barefoot. Results: There were statistically significant differences in the varus movement when wearing a 4 mm LWI (1.23 ± 2.08°, p < 0.001) versus the barefoot condition (0.35 ± 0.95°), and in the plantarflexion movement when wearing a 4 mm LWI (3.02 ± 4.58°, p < 0.001) versus the barefoot condition (0.68 ± 1.34°), in the midfoot. There were also statistically significant differences in the valgus movement when wearing a 7 mm LWI (1.74 ± 2.61°, p < 0.001) versus the barefoot condition (0.40 ± 0.90°), and in the plantar flexion movement when wearing a 4 mm LWI (2.88 ± 4.31°, p < 0.001) versus the barefoot condition (0.35 ± 0.90°), in the rearfoot. Conclusions: In the navicular bone, a varus, an abduction, and plantar flexion movements were generated. In the calcaneus, a valgus, an adduction, and plantar flexion movements were generated with the use of LWIs.

Evaluation of the Relationship between Lower Limb Hypermobility and Ankle Muscle Strength in a Paediatric Population: Protocol for a Cross Sectional Study.

The methodological heterogeneity in paediatric foot studies does not entail a stable foundation on which to focus the diagnosis and treatment of the various childhood foot problems. For this reason, the use of highly reliable tests is essential to find relationships and to establish a basis to guide the following studies. The main objective proposed in this cross-sectional observational study protocol is to examine the relationship between hypermobility (Lower Limb Assessment Score and Beighton score) and ankle muscle strength in different types of feet. The second objective is to describe the relationship between physical activity tests in children, and to compare with foot type and ankle muscle strength. The Strengthening Reporting of Observational Studies in Epidemiology (STROBE) criteria will be followed. The hypermobility, posture, strength and physical condition tests will be analyzed through three stations, each one directed by a single specialist in paediatric podiatry. The study has been approved by the Ethics Committee of the Universidad Católica San Antonio de Murcia CE112104. The results will be disseminated regardless of the magnitude or direction of effect. Intra-examiner and inter-examiner reliability will be analyzed.

Innovative Medial Cushioning Orthoses Affect Peroneus Longus Electromyographic Activity during Running.

Background: Over-supination processes of the foot and ankle involving peroneus longus (PL) damage during running sports have been treated conservatively with passive control tools, such as tapes, braces, or external ankle supports, but the effect of orthoses with typical lateral wedging orthoses (TLWO) on the muscular activity of PL during running remains unclear. Here we investigate the effects of innovative medial cushioning orthoses (IMCO) on PL activity during the full running gait cycle. In addition, we wished to ascertain the effects of innovative medial cushioning orthoses (IMCO) on PL activity during running. Methods: Thirty-one healthy recreational runners (mean age 34.5 ± 3.33) with neutral foot posture index scores, were selected to participate in the present study. They ran on a treadmill at 9 km/h wearing seven different orthoses (NRS, IMCO 3 mm, IMCO 6 mm, IMCO 9 mm, TLWO 3 mm, TLWO 6 mm and TLWO 9 mm), randomly performed on the same day while electromyographic activity of the PL muscle was recorded. Statistical intraclass correlation coefficient (ICC) to test reliability was carried out and the Wilcoxon test with Bonferroni's correction was developed to analyze the differences between the conditions. Results: the reliability of all assessments showed data higher than 0.81, that is, "almost perfect reliability"; all EMG PL values wearing either TLWO or IMCO showed a statistically significant reduction versus NRS during the fully analyzed running gait cycle; the highest difference was set on NRS 23.08 ± 6.67 to TLWO 9 mm 17.77 ± 4.794 (p < 0.001). Conclusions: Muscular EMG activity of the PL during the full running gait cycle decreases when wearing either TLWO or IMCO relative to NRS; therefore, these orthoses could be prescribed to treat the strain and overload pathologies of PL. In addition, IMCO­as it less thick, compared with TLWO­can be used when aiming to achieve better running economy.

Kinematic Effect on the Navicular Bone with the Use of Rearfoot Varus Wedge.

BACKGROUND: The rearfoot varus wedge (RVW) is a common treatment for foot pain and valgus deformity. There is research on its effects in the calcaneus, but there is little research on the navicular. More research is needed with the use of RVW due to the relationship that exists between the position of the navicular and the risk of suffering an injury. OBJECTIVES: this study sought to understand how RVW can influence the kinematics of the navicular bone, measuring their movement with the 6 SpaceFastrak system. METHODS: a total of 60 subjects participated in the study. Two sensors were used to measure the movement of the calcaneus and navicular using RVWs as compared in the barefoot position in a static way. RESULTS: there were statistically significant differences, the use of RVWs caused changes in the navicular bone, with subjects reaching the maximum varus movement with the use of RVW 7 mm of 1.35 ± 2.41° (p < 0.001), the maximum plantar movement flexion with the use of RVW 10 mm of 3.93 ± 4.44° (p < 0.001). CONCLUSIONS: when RVWs were placed under the calcaneus bone, the navicular bone response was in varus movement too; thus, the use of rearfoot varus wedge can influence the movement of the navicular bone.

Assessment of a New Lateral Cushioned Casting Orthosis: Effects on Peroneus Longus Muscle Electromyographic Activity During Running.

BACKGROUND: Classical medial wedge (CMW) orthoses have been prescribed to treat overpronation foot pathologies in runners. The effects of a novel supination orthosis (NSO) on the surface electromyography (EMG) activity of the peroneus longus (PL) muscle during a complete cycle of running have yet to be tested. PURPOSE/HYPOTHESIS: The purpose of this study was to compare the EMG activity of the PL in participants wearing CMW orthoses and NSOs versus neutral running shoes (NRS) during a full cycle of running gait. It was hypothesized that the PL muscle activity would be lower for the NSO compared with CMW or NRS. STUDY DESIGN: Controlled laboratory study. METHODS: Included were 31 healthy recreational runners of both sexes (14 male and 17 female; mean age, 38.58 ± 4.02 years) with a neutral Foot Posture Index and standard rearfoot-strike pattern. Participants ran on a treadmill at 9 km/h while wearing NSO (3-, 6-, and 9-mm thicknesses), CMW (3-, 6-, and 9-mm thicknesses), and NRS, for a total of 7 different conditions randomly selected, while the EMG signal activity of the PL was recorded for 30 seconds. Each trial was recorded 3 times, and the intraclass correlation coefficient (ICC) to test reliability of the measurements was calculated. The Wilcoxon pair to pair nonparametric test with Bonferroni correction was performed to analyze differences among the conditions. RESULTS: The reliability of all assessments was almost perfect (ICC, >0.81). For both the CMW and NSO, regardless of thickness, the PL activity was statistically significantly lower compared with the NRS (P < .05 for all). For all CMW thicknesses, the PL activity was lower compared with the respective NSO thicknesses, with the 3-mm thickness having the largest difference (CMW3mm, 18.63 ± 4.64 vs NSO3mm, 20.78 ± 4.99 mV; P < .001). CONCLUSION: Both CMW and NSO produced reduced EMG activity of the PL muscle; therefore, they can be prescribed to treat overpronation pathologies without associated PL strain concerns. In addition, the NSO saved the enhancement material placed on the medial-rear side of CMW, making it easier to wear sports shoes. CLINICAL RELEVANCE: Knowing the safety of CMW and NSO will aid in understanding treatments for overpronation pathologies.