Effect of Postural Insoles on Stability and Leg Muscular Activity

Study Overview
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Brief Summary
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Posturology allows to treat postural problems by using postural insoles, which will have an effect at the neurophysiological level. Pieces of 1 to 3 millimeters are inserted to stimulate specific receptors located on the sole of the foot, which will affect the muscular proprioception and modify the activation of the ascending muscle chains. The hypothesis of this work is based on the fact that the use of postural insoles with a 2 millimeters metatarsal bar will influence the displacement of the center of pressure and the muscle activity of the leg when compared with a placebo insoles. Participants will be healthy subjects and will be divided into two groups, control and experimental. Subjects in the control group will be given a pair of flat insoles (placebo insoles) with 1.2 millimeters polyester resin. Those of the experimental group will be made the same insoles but they will include by thermal fusion a metatarsal bar of 2 millimeters polyester resin in the metatarsal zone corresponding to the 1st, 2nd, 3rd and 4th metatarsal head. Postural stability analysis will be performed with the force platform of the Biomechanics Institute of Valencia (IBV-Spain) and at the same time an electromyographic analysis in the dominant leg with a surface electromyograph system. Subjects will be assessed with their eyes open and closed under two situations, with footwear and with footwear and insoles.

Official Title
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Effect of Postural Metatarsal Bar Orthotic Element on Stability and Leg Muscular Activity. A Randomized Clinical Trial

Conditions
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Postural Stability, Muscular Activity

Intervention / Treatment
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* Diagnostic Test: Postural stability assessment with a force platform.
* Diagnostic Test: Muscular assessment with a electromyograph


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy subjects with no discomfort in gait Subjects with not muscle and skeletal diseases Exclusion Criteria: Subjects with balance disorders, pain at legs Subjects with loss of balance

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Flat Insole (no metatarsal bar)<br>Postural stability and electromyographic activity in the dominant leg will be assessed with the subject shod (closed clog) and with 1.2 millimeters flat polyester resin insoles. | Diagnostic Test: Postural stability assessment with a force platform.<br>* The postural stability will be assessed in static by means of the antero-posterior and medio-lateral displacements of the center of pressure in Romberg open and closed eyes test measured with a force platform (NED/SVE-IBV-Spain). Three 30-second measurements will be made in each condition.<br>Diagnostic Test: Muscular assessment with a electromyograph<br>* The activity of the medial and lateral gastrocnemius, soleus and anterior tibial muscles of the dominant leg will be assessed with the mDurance surface electromiograph at the same time as postural stability analysis is performed.Three 30-second measurements will be made in each condition.<br>|
| Experimental: Flat Insole (with 2 millimeters metatarsal bar)<br>Postural stability and electromyographic activity in the dominant leg will be assessed with the subject shod (closed clog) and with 1.2 millimeters flat polyester resin insoles with a 2 millimeters polyester resin metatarsal bar. | Diagnostic Test: Postural stability assessment with a force platform.<br>* The postural stability will be assessed in static by means of the antero-posterior and medio-lateral displacements of the center of pressure in Romberg open and closed eyes test measured with a force platform (NED/SVE-IBV-Spain). Three 30-second measurements will be made in each condition.<br>Diagnostic Test: Muscular assessment with a electromyograph<br>* The activity of the medial and lateral gastrocnemius, soleus and anterior tibial muscles of the dominant leg will be assessed with the mDurance surface electromiograph at the same time as postural stability analysis is performed.Three 30-second measurements will be made in each condition.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of postural balance | The mediolateral and anteroposterior excursion of centre of pressures will be measured in millimeters with a force platform with and without the insoles | From baseline to 10 minutes | 
| Change of muscular activity | The muscular activity in gastrocnemius, soleus and tibialis anterioris will be measured as a percentage (%) with a surface electromyograph in one leg with and without the insoles | From baseline to 10 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Metatarsal Bar, Insoles, Postural stability, Electromyograph Activity