Muscle Activation of the Lower Limb in Response to a Medio-lateral Imbalance in Monopodal Stance (SM01)

Muscle Activation of the Lower Limb in Healthy Subjects in Response to a Medio-lateral Imbalance in Monopodal Stance: a Preliminary Study

The "static" single-leg stance has been extensively studied in the literature for its relevance in functional evaluation, therapeutic exercise, sports training and research for fall prevention (particularly for the elderly and patients with neurological diseases). However, the motor strategies of the supporting limb have been investigated only at the ankle level. In particular it is not known, at the hip, how the muscular system reacts to medial and lateral imbalances. Colonna has hypothesized, basing on a myofascial chains approach, that the balance is managed by the front and back spiral chains. The aim of the present study is to perform a preliminary experimental analysis to verify Colonna's hypothesis, testing a method for the investigation of motor strategies underlying equilibrium.

Five healthy subjects will be examined by means of electromyographic analysis of the gluteus maximus, gluteus medius, adductor longus, tibialis anterior and peroneus longus. Subjects will undergo perturbations of their monopodal balance.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Other: Medio-lateral imbalance

Detailed Description

The subjects involved in the research will be analyzed at the LAMBDA laboratory (UDGEE), AUSL-IRCCS (Azienda Unità Sanitaria Locale-Istituto di Ricovero e Cura a Carattere Scientifico) di Reggio Emilia.

The analysis will be carried out on the right lower limb of each subject. The electromyographic devices will be applied to the tibialis anterior, peroneus longus, gluteus medius, gluteus maximus and adductor longus.

Reflective markers will then be applied (using double-sided tape) according to the Total3DGait protocol, which identifies the body segments of the forearms, arms, trunk, pelvis, thighs, legs, and feet.

The subject must position himself with his right foot on a force platform. The toe of the left foot will be allowed to rest on the ground (on the other power platform posteriorly placed), with the verbal indication to load as little weight as possible on it: this indication is aimed at reducing muscle activation in the absence of external perturbations, in order to highlight only the activity caused by the perturbations themselves. Only acquisitions in which the load on the left foot will be less than 30% of the weight will be considered valid.

The hands will be placed on the hips to limit the variables to be controlled and to standardize the posture, in order to focus the contribution to the balance of the lower limb. The left thigh has to be kept vertical. Finally, it will be required to find, within the constraints described above, the posture that is as comfortable as possible, with minimal muscle contraction. The distance between the feet is therefore freely chosen by each subject.

The operator positions himself behind the subject to be examined, and without being seen performs lateral thrusts with the medial margin of the hand at the proximal third of the thigh. At least ten pushes per side will be performed, with random timing. The thrusts will be quick but without causing pain.

The operator will then request maximal contractions from the subject, in order to normalize the electrical activity of each muscle with respect to its maximum. It will be required to perform the dorsiflexion and pronation of the foot against resistance, then the adduction, abduction and extension of the hip.

• Study Type: Interventional
• Enrollment (Actual): 5
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Italy
  • Reggio Emilia, Italy, 42122
    • AUSL-IRCCS di Reggio Emilia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• All healthy subjects

Exclusion Criteria:

• skeletal pathologies compromising balance
• neuromotor pathologies compromising balance

Study Plan

How is the study designed?

Design Details

• Primary Purpose: BASIC_SCIENCE
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Unbalanced healthy subjects; Subjects undergo an external perturbation of their balance	Other: Medio-lateral imbalance; Thrust on the pelvis in the medio-lateral direction in order to create a balance perturbation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maximum electrical intensity during early response of muscle activation	The muscles considered will be, for the anterior spiral chain, the adductor longus and the peroneus longus, for the posterior spiral chain, the glutei (medius and maximus) and the tibialis anterior. For each muscle, the intensity will be normalized to the intensity of the maximal contraction. Muscle activity will be evaluated for 1500ms, 500ms before and 1000ms after the thrust. The early response to the stimulus will be identified in the interval of 100-500ms after the thrust.The thrusts will be performed 10 times towards the medial direction and 10 towards the lateral. The median intensity for each direction will be calculated.	During the procedure
Correlation of muscle activity	Correlation coefficients of the activation intensity between each muscle of the hip and each muscle of the ankle: tibialis anterior-glutei; tibialis anterior-adductor longus; peroneus longus-glutei; peroneus longus-adductor longus. Calculated for each imbalance direction.	During the procedure

Collaborators and Investigators

• Sponsor: Manusapiens

Publications and helpful links

General Publications

• Colonna S., 2012. Le catene miofasciali in medicina manuale - Arto inferiore: Ginocchio, Ed. Martina.
• Morey-Klapsing G, Arampatzis A, Bruggemann GP. Joint stabilising response to lateral and medial tilts. Clin Biomech (Bristol, Avon). 2005 Jun;20(5):517-25. doi: 10.1016/j.clinbiomech.2005.01.008.

Study record dates

Study Major Dates

• Study Start (ACTUAL): August 1, 2021
• Primary Completion (ACTUAL): November 1, 2021
• Study Completion (ACTUAL): December 30, 2021

Study Registration Dates

• First Submitted: August 26, 2021
• First Submitted That Met QC Criteria: October 1, 2021
• First Posted (ACTUAL): October 15, 2021

Study Record Updates

• Last Update Posted (ACTUAL): October 17, 2022
• Last Update Submitted That Met QC Criteria: October 13, 2022
• Last Verified: October 1, 2021

More Information

Terms related to this study

• Keywords: electromyography; human balance; monopodal stance; myofascial chains
• Other Study ID Numbers: 957/2020/SPER/AUSLRE

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No