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Updated: Jan 30, 2026
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Standing Neurophysiological Assessment of Lower Extremity Muscles Post-Stroke
Published on: July 26, 2021
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Upright standing after stroke: How loading-unloading mechanism participates to the postural stabilization
Patrice R Rougier1, Dominic Pérennou2
1Laboratoire Interuniversitaire de Biologie de la Motricité, EA 7424, Université de Savoie, Domaine Scientifique de Savoie-Technolac, 73 376 Le Bourget du Lac cedex, France.
Human Movement Science
|January 19, 2019
Summary
Stroke patients primarily use ankle movements for balance, even with severe deficits. Rehabilitation should focus on this ankle strategy, not hip control, for better postural stability.
Area of Science:
- Neuroscience
- Biomechanics
- Rehabilitation Medicine
Background:
- Understanding postural strategies in hemiparetic stroke patients is crucial for effective rehabilitation.
- Two main mechanisms, loading-unloading (LU) and pressure distribution (PD), stabilize standing posture.
- It was hypothesized that LU is the predominant strategy in hemiparetic patients.
Purpose of the Study:
- To investigate the postural strategies employed by hemiparetic stroke patients.
- To compare the contributions of LU and PD mechanisms in hemiparetic patients versus healthy controls.
- To inform the development of targeted postural rehabilitation interventions.
Main Methods:
- Posturographic assessments using a dual force-platform.
- Inclusion of 30 hemiparetic patients (3 months post-stroke) and 30 matched healthy controls.
- Calculation of original indices (0-1) to quantify LU and PD contributions.
Main Results:
- Mediolateral axis: LU contribution was high and similar in both groups, indicating hip involvement.
- Anteroposterior axis: PD contribution was near 1 in controls (ankle involvement) and slightly lower but still predominant (>0.5) in hemiparetics.
- PD contribution correlated inversely with sensory and motor deficits, suggesting preserved ankle control.
Conclusions:
- Hemiparetic patients predominantly use pressure distribution (PD) for anteroposterior postural control, primarily involving ankle movements.
- This ankle strategy, driven by the non-paretic limb, is maintained even with significant sensory or motor impairments.
- Rehabilitation should prioritize enhancing this ankle-based postural control rather than focusing on hip strategies.
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