Postural Responses to External Perturbation in Post-Stroke

Postural Responses to External Perturbation in Post-Stroke: Sensorimotor Integration and Rehabilitation

To maintain stable body balance in daily activities, the ability to respond to external perturbations is an essential factor. Such capacity is limited in pathological conditions, such as in stroke, in which postural control is impaired due to lesions to the central nervous system. Impairment to postural control increases body sway during upright posture and leads to augmented frequency of falls. In this sense, the identification of mechanisms involved in body balance disorders after stroke is particularly important in situations of postural perturbation. The purpose of this project is to evaluate reactive postural responses to unpredictable external perturbations, analyzing postural dysfunctions caused by lesion to different brain areas as a result of stroke, and test principles of dynamic body balance rehabilitation.

Study Overview

• Status: Unknown
• Conditions: Stroke
• Intervention / Treatment: Other: Sensory Intervention

• Study Type: Interventional
• Enrollment (Anticipated): 24
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • São Paulo, Brazil, 05508-030
    • Escola de Educação física e Esporte, Universidade de São Paulo

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 45 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Inclusion criteria are as follows. Healthy participants: absence of detectable neurological or physical malfunction which might affect postural control, no use of drugs affecting body balance and preserved mental capacity. Stroke patients: capacity to sustain independently orthostatic posture for at least 5 min. and preserved mental capacity.

Exclusion Criteria:

• Exclusion Criteria are: no orthopedic malfunction, no clinical instability associated with systemic disease, no use of drugs affecting body balance and presence of "pusher syndrome".

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Sensory Conditions	Other: Sensory Intervention; full sensory information, whose participants will practice balancing tasks without constraint sensory body;; sensory constraint, whose participants will practice the same balance tasks with constraint body of visual and tactile information from the soles of the feet;; control, whose participants will exercise activities involving cognitive and upper limbs.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Displacement amplitude of the CP to the anterior-posterior and medial-lateral	This outcome measure quantified by the difference between the maximum values of the anterior-posterior and medial-lateral after the start of trial and average position in the axis anteroposterior and mediolateral, respectively, in the 200 ms prior to the onset of the trial.	2 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Coordination between the hip and ankle joint	Coordination between the hip and ankle joints, which is evaluated by adjusting the angle displacement data, hip and ankle angle within 95% of an ellipse surrounding the values of the disturbance moment until the end of the trial. Will be carried out a regression analysis to identify the slope of the fitted ellipse. Slopes greater indicate a greater share of the ankle in relation to the hip	2 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle activation latency	This outcome measure is time between the time of release and the first load value 3 standard deviations above the mean magnitude in the 200 ms prior to postural disturbance, with subsequent values increasing.	2 months

Collaborators and Investigators

• Sponsor: University of Sao Paulo
• Investigators: Study Director: Luis A Teixeira, PhD

Study record dates

Study Major Dates

• Study Start: August 1, 2013
• Primary Completion (Anticipated): February 1, 2014
• Study Completion (Anticipated): October 1, 2014

Study Registration Dates

• First Submitted: July 26, 2013
• First Submitted That Met QC Criteria: July 29, 2013
• First Posted (Estimate): July 31, 2013

Study Record Updates

• Last Update Posted (Estimate): August 1, 2013
• Last Update Submitted That Met QC Criteria: July 30, 2013
• Last Verified: July 1, 2013

More Information

Terms related to this study

• Keywords: Rehabilitation; Cerebrovascular Accident; Sensory System
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Stroke
• Other Study ID Numbers: SMH-2011/18173-3