Inter-individual variability in the relationship between propulsion force and walking speed in subacute stroke

Area of Science:

• Biomechanics
• Neurology
• Rehabilitation Science

Background:

• Walking speed is crucial for mobility and independence.
• Propulsion force, particularly in late stance, is a key determinant of walking speed.
• Inter-individual variability exists in how propulsion force influences walking speed, especially in clinical populations.

Purpose of the Study:

• To investigate variability in the propulsion force-walking speed relationship in subacute stroke patients.
• To identify clinical characteristics associated with this inter-individual variability.
• To inform tailored rehabilitation strategies for stroke survivors.

Main Methods:

• Twenty-five subacute stroke participants performed walking trials at self-selected and maximal speeds.
• Hierarchical linear modeling was used to analyze group and individual-level effects.
• Bayesian network analysis examined associations between clinical characteristics and propulsion force-walking speed relationships.

Main Results:

• Significant inter-individual variability was found in the effect of propulsion force on walking speed.
• A negative association was observed between Trunk Impairment Scale scores and paretic propulsion force regression coefficients (r=-0.42).
• A negative association was found between non-paretic and paretic propulsion force regression coefficients (r=-0.48).

Conclusions:

• Stroke patients exhibit unique patterns in how propulsion force affects their walking speed.
• Impaired trunk function may lead to increased reliance on the paretic limb for propulsion.
• Understanding these patient-specific patterns is vital for developing effective, individualized rehabilitation interventions.