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Published on: April 12, 2016
Balance during obstacle crossing following stroke
Catherine M Said1, Patricia A Goldie, Aftab E Patla
1Heidelberg Repatriation Hospital, Heidelberg West, 3081, Victoria, Australia. Cathy.Said@austin.org.au
Gait & Posture
|February 6, 2007
Summary
Stroke survivors exhibit altered balance control when navigating obstacles, potentially explaining their increased fall risk. This study analyzed how stroke impacts obstacle crossing, revealing key biomechanical differences.
Area of Science:
- Biomechanics
- Neurology
- Rehabilitation Science
Background:
- Falls are a significant concern for stroke survivors, often linked to impaired balance.
- Obstacle negotiation is a complex task that challenges balance control.
Purpose of the Study:
- To investigate the effects of stroke on balance during obstacle crossing.
- To compare biomechanical parameters between stroke survivors and unimpaired individuals during obstacle negotiation.
Main Methods:
- Measured center of mass (COM) and center of pressure (COP) in 12 stroke subjects and 12 controls.
- Subjects stepped over a 4 cm obstacle at self-selected and matched speeds.
- Analyzed anterior-posterior (AP) separation and velocity of COM and COP.
Main Results:
- Stroke subjects showed increased AP COM-COP separation during unaffected lead toe clearance, suggesting instability.
- Reduced step lengths before and after the obstacle were observed in stroke survivors.
- Stroke survivors demonstrated reduced AP COM velocity at affected lead toe off and more posterior COM/COP positioning during affected lead toe clearance, likely for stability.
Conclusions:
- Stroke significantly alters balance strategies during obstacle crossing, with adaptations aimed at enhancing stability.
- These findings highlight specific biomechanical deficits that may contribute to falls in stroke survivors.
- Understanding these adaptations is crucial for developing targeted interventions to improve mobility and reduce fall risk.
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