Arch index and running biomechanics in children aged 10-14 years

Which Factors Influence Running Gait in Children and Adolescents? A Narrative Review

In recent years, running has dramatically increased in children and adolescents, creating a need for a better understanding of running gait in this population; however, research on this topic is still limited. During childhood and adolescence multiple factors exist that likely influence and shape a child's running mechanics and contribute to the high variability in running patterns. The aim of this narrative review was to gather together and assess the current evidence on the different factors that influence running gait throughout youth development. Factors were classified as organismic, environmental, or task-related. Age, body mass and composition, and leg length were the most researched factors, and all evidence was in favour of an impact on running gait. Sex, training, and footwear were also extensively researched; however, whereas the findings concerning footwear were all in support of an impact on running gait, those concerning sex and training were inconsistent. The remaining factors were moderately researched with the exception of strength, perceived exertion, and running history for which evidence was particularly limited. Nevertheless, all were in support of an impact on running gait. Running gait is multifactorial and many of the factors discussed are likely interdependent. Caution should therefore be taken when interpreting the effects of different factors in isolation.

Toward improved understanding of foot shape, foot posture, and foot biomechanics during running: A narrative review

The current narrative review has explored known associations between foot shape, foot posture, and foot conditions during running. The artificial intelligence was found to be a useful metric of foot posture but was less useful in developing and obese individuals. Care should be taken when using the foot posture index to associate pronation with injury risk, and the Achilles tendon and longitudinal arch angles are required to elucidate the risk. The statistical shape modeling (SSM) may derive learnt information from population-based inference and fill in missing data from personalized information. Bone shapes and tissue morphology have been associated with pathology, gender, age, and height and may develop rapid population-specific foot classifiers. Based on this review, future studies are suggested for 1) tracking the internal multi-segmental foot motion and mapping the biplanar 2D motion to 3D shape motion using the SSM; 2) implementing multivariate machine learning or convolutional neural network to address nonlinear correlations in foot mechanics with shape or posture; 3) standardizing wearable data for rapid prediction of instant mechanics, load accumulation, injury risks and adaptation in foot tissue and bones, and correlation with shapes; 4) analyzing dynamic shape and posture via marker-less and real-time techniques under real-life scenarios for precise evaluation of clinical foot conditions and performance-fit footwear development.

How barefoot and conventional shoes affect the foot and gait characteristics in toddlers

Objectives

Barefoot shoes have recently become a popular alternative to conventional shoes among the parents of pre-school children. As the long-term effect of habitual shoe-wearing on the foot is still unclear, the aim of this study was to compare the arch index, dynamic foot anthropometry and gait parameters in toddlers who had been habitually wearing barefoot shoes or conventional shoes since their first steps.

Methods

30 toddlers– 15 habitually wearing barefoot shoes (BF group) and 15 habitually wearing conventional shoes (N-BF group)–participated in this study. Each child was measured twice during the study. The first data collection session occurred within one month after the first five consecutive unsupported steps were performed by the toddler. The second data collection session occurred seven months after this event. At each data collection session, the toddler was instructed to walk barefooted at its natural speed over an Emed^® platform (Novel GmbH, Germany). The Emed ^® software generated data regarding the arch index, dynamic foot anthropometry, foot progression angle, contact area, contact time, peak pressure and maximum force. The Wilcoxon signed-rank test was used to compare the differences between the 1^st and 2^nd data collections. The Mann-Whitney U test was used to compare the differences between the BF and N-BF groups.

Results

The results of this study show a higher plantar arch and a smaller foot progression angle in the BF group. The forefoot width in both the BF and N-BF groups remained proportional to the foot length after seven months of independent walking.

Conclusions

These findings may encourage parents and caregivers to introduce barefoot shoes or create a habitual barefoot time for their child.

SUBTALAR JOINT IN NEUTRAL AND RELAXED POSITIONS FOR EVALUATION OF MEDIAL LONGITUDINAL ARCH

OBJECTIVE

The medial longitudinal arch is the main structure of load bearing and shock absorption of the foot. The evaluation of medial longitudinal arch, such as the navicular height, the medial longitudinal arch angle and the Feiss line should be performed with the subtalar joint in the neutral and relaxed position. Our study analyzed the correlation between the measurements of the subtalar joint in neutral and relaxed positions during the evaluation tests of the medial longitudinal arch.

METHODS

This is a cross-sectional study, in which 51 healthy volunteers (102 feet; 36 women; 28 ± 5 years, 1.66 ± 0.10 m; 24.5 ± 4.5 kg/m2) had their navicular height, medial longitudinal arch angle and Feiss line measured in the neutral and relaxed positions. The correlation between the measures was evaluated using Pearson's test.

RESULTS

A strong correlation of the 102 feet Feiss line measurements between neutral and relaxed positions (r = 0.81) was observed, and a moderate correlation between the medial longitudinal arch angle (r = 0.78) and between navicular height in neutral and relaxed positions (r = 0.76).

CONCLUSION

The measurements of the longitudinal medial arch between the neutral and relaxed positions are strongly correlated. Therefore, it is not necessary to measure the medial longitudinal arch in both neutral and relaxed positions. Level of Evidence II, Diagnostic Studies - Investigating a diagnostic test.

The effect of changing foot progression angle using real-time visual feedback on rearfoot eversion during running

Atypical rearfoot in/eversion may be an important risk factor for running-related injuries. Prominent interventions for atypical rearfoot eversion include foot orthoses, footwear, and taping but a modification derived from gait retraining to correct atypical rearfoot in/eversion is lacking. We aimed to investigate changes in rearfoot in/eversion, subtalar pronation, medial longitudinal arch angle, and selected lower limb joint biomechanics while performing toe-in/toe-out running using real-time visual feedback. Fifteen female runners participated in this study. Subjects performed toe-in/toe-out running using real-time visual feedback on foot progression angle, which was set ±5° from habitual foot progression angle. 3D kinematics of rearfoot in/eversion, subtalar supination/pronation, medial longitudinal arch angle, foot progression angle, hip flexion, ab/adduction and internal/external rotation, knee flexion, ankle dorsiflexion, and ankle power were analyzed. A repeated-measures ANOVA followed by pairwise comparisons was used to analyze changes between three conditions. Toe-in running compared to normal and toe-out running reduced peak rearfoot eversion (mean difference (MD) with normal = 2.1°; p<0.001, MD with toe-out = 3.5°; p<0.001), peak pronation (MD with normal = -2.0°; p<0.001, MD with toe-out = -3.4; p = <0.001), and peak medial longitudinal arch angle (MD with normal = -0.7°; p = 0.022, MD with toe-out = -0.9; p = 0.005). Toe-out running significantly increased these kinematic factors compared to normal and toe-in running. Toe-in running compared to normal running increased peak hip internal rotation (MD = 2.3; p<0.001), and reduced peak knee flexion (MD = 1.3; p = 0.014). Toe-out running compared to normal running reduced peak hip internal rotation (MD = 2.5; p<0.001), peak hip ab/adduction (MD = 2.5; p<0.001), peak knee flexion (MD = 1.5; p = 0.003), peak ankle dorsiflexion (MD = 1.6; p<0.001), and peak ankle power (MD = 1.3; p = 0.001). Runners were able to change their foot progression angle when receiving real-time visual feedback for foot progression angle. Toe-in/toe-out running altered rearfoot kinematics and medial longitudinal arch angle, therefore supporting the potential value of gait retraining focused on foot progression angle using real-time visual feedback when atypical rearfoot in/eversion needs to be modified. It should be considered that changes in foot progression angle when running is accompanied by changes in lower limb joint biomechanics.

The relationship between static and dynamic foot posture and running biomechanics: A systematic review and meta-analysis

BACKGROUND

Medial longitudinal arch characteristics are thought to be a contributing factor to lower limb running injuries. Running biomechanics associated with different foot types have been proposed as one of the potential underlying mechanisms. However, no systematic review has investigated this relationship.

RESEARCH QUESTION

The aim of this study was to conduct a systematic literature search and synthesize the evidence about the relationship between foot posture and running biomechanics.

METHODS

For this systematic review and meta-analysis different electronic databases (Pubmed, Web of Science, Cochrane, SportDiscus) were searched to identify studies investigating the relationship between medial longitudinal arch characteristics and running biomechanics. After identification of relevant articles, two independent researchers determined the risk of bias of included studies. For homogenous outcomes, data pooling and meta-analysis (random effects model) was performed, and levels of evidence determined.

RESULTS

Of the 4088 studies initially identified, a total of 25 studies were included in the qualitative review and seven in the quantitative analysis. Most studies had moderate and three studies a low risk of bias. Moderate evidence was found for a relationship between foot posture and subtalar joint kinematics (small pooled effects: -0.59; 95%CI -1.14 to - 0.003) and leg stiffness (small pooled effect: 0.59; 95%CI 0.18 to 0.99). Limited or very limited evidence was found for a relationship with forefoot kinematics, tibial/leg rotation, tibial acceleration/shock, plantar pressure distribution, plantar fascia tension and ankle kinetics as well as an interaction of foot type and footwear regarding tibial rotation.

SIGNIFICANCE

While there is evidence for an association between foot posture and subtalar joint kinematics and leg stiffness, no clear relationship was found for other biomechanical outcomes. Since a comprehensive meta-analysis was limited by the heterogeneity of included studies future research would benefit from consensus in foot assessment and more homogenous study designs.