Functional differences between lower limbs during gait in relation to fall risk

Area of Science:

• Biomechanics
• Gerontology
• Gait Analysis

Background:

• Gait exhibits functional asymmetry between dominant and non-dominant lower limbs.
• Local dynamic stability is crucial for fall risk assessment.
• Limb asymmetry in local dynamic stability during gait remains under-investigated.

Purpose of the Study:

• To investigate differences in local dynamic stability between dominant and non-dominant limbs in elderly individuals.
• To explore the relationship between limb-specific dynamic stability and fall occurrence.

Main Methods:

• 131 elderly participants (mean age 71.0 ± 6.8 years) were studied.
• Local dynamic stability was measured using shank-mounted accelerometers, calculating Lyapunov exponents (LE) in vertical, medial-lateral, and anterior-posterior directions.
• Fall occurrence was monitored prospectively over one year.

Main Results:

• Significant limb asymmetries were found in local dynamic stability parameters.
• The non-dominant limb showed better medial-lateral stability, while the dominant limb had lower anterior-posterior LE.
• A significant limb × group interaction for medial-lateral LE indicated altered asymmetry patterns in fallers.

Conclusions:

• Functional asymmetry exists between lower limbs in local dynamic stability during gait.
• Limb roles in stability reflect long-term adaptations rather than acute responses.
• Altered asymmetry patterns may be associated with increased fall risk in the elderly.