Effect of long term use of arch support foot orthoses on walking ground reaction force asymmetry index in children with flexible flat feet: A cohort study

Context:Flat foot is one of the lower extremity deformities that might change kinetic variables of gait. Fatigue is one of the factors that can alter the vertical ground-reaction force (GRF). The effect of a fatiguing condition on vertical GRF has not been documented in individuals with flat feet.Objective:To examine the fatigue effect on vertical GRF in individuals with flat feet compared with a normal group during barefoot walking.Design:Repeated-measure ANOVA for the effects of fatigue on individuals with flat feet and normal feet.Setting:Biomechanics laboratory.Participants:17 subjects with flat feet and 17 normal subjects (recruited according to their arch-height ratio).Main Outcome Measures:Three vertical GRF measures (F1, the first peak force; F2, minimum force; and F3, the second peak force) were extracted before and after a functional fatigue protocol.Results:No significant interaction between fatigue and group was observed for the 3 vertical GRF measures. For F2, fatigue and group effects were significant (P = .001 and P = .02, respectively). Furthermore, F2 was higher in the flat-feet group than in the normal group; F2 also increased after fatigue. For F3, only a significant fatigue effect was observed (P = .004). F3 decreased after fatigue in both groups.Conclusions:In the flat-feet group, a decrease in the variation of vertical GRF might be due to more flexible foot joints. After fatigue, muscles might lose their ability to control the foot joints and cause higher F2 in the flat-feet group.

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Effect of foot orthoses on magnitude and timing of rearfoot and tibial motions, ground reaction force and knee moment during running

Journal of Science and Medicine in Sport ◽

10.1016/j.jsams.2008.05.001 ◽

2009 ◽

Vol 12 (6) ◽

pp. 679-684 ◽

Cited By ~ 27

Author(s):

Mansour Eslami ◽

Mickaël Begon ◽

Sébastien Hinse ◽

Heydar Sadeghi ◽

Peter Popov ◽

...

Keyword(s):

Ground Reaction Force ◽

Reaction Force ◽

Foot Orthoses

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Biomechanical asymmetries persist after ACL reconstruction: results of a 2-year study

Journal of Experimental Orthopaedics ◽

10.1186/s40634-020-00301-2 ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Fatemeh Sharafoddin-Shirazi ◽

Amir Letafatkar ◽

Jennifer Hogg ◽

Vahid Saatchian

Keyword(s):

Ground Reaction Force ◽

Reaction Force ◽

Force Plate ◽

Asymmetry Index ◽

Knee Adduction Moment ◽

Vertical Ground Reaction Force ◽

Level Of Evidence ◽

Post Surgery ◽

Peak Knee ◽

Flexion Moment

Abstract Purpose This study was aimed to examine longitudinal (6, 12, 18, 24 months) asymmetries in double-leg landing kinetics and kinematics of subjects with and without unilateral ACLR. Methods Three-dimensional kinematic and kinetic parameters of 40 participants (n = 20 post-ACLR, n = 20 healthy) were collected with a motion analysis system and force plate during a drop-landing task, and asymmetry indices were compared between groups. Results The asymmetry index (AI) in the ACLR group compared to the healthy group decreased from six to 24 months for vertical ground reaction force (vGRF) from 100% to 6.5% and for anterior posterior ground reaction force (a-pGRF) from 155.5% to 7%. Also, the AI decreased for peak hip flexion moment from 74.5% to 17.1%, peak knee flexion moment from 79.0% to 5.8% and peak ankle dorsiflexion moment from 59.3% to 5.9%. As a further matter, the AI decreased for peak hip abduction moment from 67.8% to 5.1%, peak knee adduction moment from 55.7% to 14.8% and peak knee valgus angle from 48.7% to 23.5%. Conclusions Results obtained from this longitudinal study showed that ACLR patients still suffer from limb asymmetries during landing tasks, which appear to normalize by 24-monthspost-surgery. This finding can help us to better understand biomechanics of the limbs after ACLR, and design more efficient post-surgery rehabilitation programs. Level of evidence Level III.

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Altered Vertical Ground Reaction Force Components While Walking in Individuals With Chronic Ankle Instability

International Journal of Athletic Therapy & Training ◽

10.1123/ijatt.2018-0117 ◽

2020 ◽

Vol 25 (1) ◽

pp. 27-30

Author(s):

Erik A. Wikstrom ◽

Kyeongtak Song ◽

Kimmery Migel ◽

Chris J. Hass

Keyword(s):

Ground Reaction Force ◽

Loading Rate ◽

Ankle Instability ◽

Reaction Force ◽

Chronic Ankle Instability ◽

Vertical Ground Reaction Force ◽

Time To Peak ◽

Vertical Ground ◽

Force Components

Aberrant loading is a mechanism by which individuals with chronic ankle instability (CAI) may negatively impact cartilage health and therefore long-term health outcomes. We aimed to quantify walking vertical ground reaction force (vGRF) component differences between those with and without CAI. Participants (n = 36) walked barefoot overground at a self-selected comfortable pace. Normalized peak vGRF, time to peak vGRF, and normalized loading rate were calculated. Higher normalized loading rates (CAI: 5.69 ± 0.62 N/BW/s; controls: 5.30 ± 0.44 N/BW/s, p = .034) and less time to peak vGRF (CAI: 1.48 ± 0.18 s; controls: 1.62 ± 0.16 s, p = .018) were observed in those with CAI. In conclusion, those with CAI demonstrate a higher normalized loading rate and less time to peak vGRF compared to controls.

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