Utilizing Kernel Density Estimation and Butterfly Diagram to Characterize the Gait Variability in the Fallers: A...

Area of Science:

• Biomechanics
• Gerontology
• Gait Analysis

Background:

• The butterfly diagram is a recognized tool for visualizing elderly gait patterns and identifying instability.
• Quantifying variability at butterfly diagram intersections remains underexplored.
• This study addresses the need for advanced analytical methods to assess gait variability in elderly fallers.

Purpose of the Study:

• To propose and validate Kernel Density Estimation (KDE) and Center of Pressure (COP) symmetry index for analyzing butterfly diagram intersections.
• To characterize gait variability and identify potential fall risk factors in elderly individuals.
• To offer insights for targeted interventions to reduce fall risk.

Main Methods:

• Twenty active elderly individuals (fallers and non-fallers) participated.
• Gait was assessed on a treadmill at self-selected speeds, followed by a 60-second walking trial.
• Bilateral toe-off (TO) and initial contact (IC) points were identified to compute COP symmetry index and analyze TO-IC intersections using KDE.

Main Results:

• Fallers demonstrated a significantly higher COP symmetry index compared to non-fallers (p=0.03).
• No significant differences were observed in step width, step length, or COP distances between groups (p > 0.05).
• KDE revealed distinct gait variability patterns: two for non-fallers and three for fallers, indicating greater instability in fallers.

Conclusions:

• KDE and COP symmetry analysis effectively quantify gait variability in elderly individuals.
• These methods provide valuable insights into fall risk factors.
• The findings suggest potential targets for interventions aimed at improving gait stability in elderly women.