@incollection{sarvestan2024gait,
author = "Javad Sarvestan and Jens Seemann and Silvia Del Din and Matthis Synofzik and Winfried Ilg and Lisa Alcock",
abstract = "Introduction: Monitoring gait with wearable sensors provides an opportunity for improving clinical management and evaluating therapeutic interventions in patients with degenerative cerebellar ataxia (DCA). While multi-sensor configurations are recommended for robust gait evaluation, using a single sensor offers several advantages including reduced data footprint, minimized patient burden, and extended battery life.
Methods: 96 participants (control: n=42; preclinical DCA: n=19; clinical DCA: n=35) completed two 25m straight walks at their self-selected preferred pace in a laboratory setting. A wearable sensor (APDM, Opal 128Hz) was affixed to the lower back and the dorsum of both feet. Gait events (initial contact-IC, final contact-FC) were detected using a single sensor and multiple sensors (reference system). Agreement between the single and multi-sensor configurations (bias, limits of agreement, intraclass correlation coefficient) and accuracy (Positive predictive value; PPV, median absolute error; MAE) were quantified. Relationships between event detection accuracy and gait outcomes derived by the reference system were explored.
Results: A total of 8473 steps were included in the analyses. Accuracy was high for identification of IC in controls (PPV=97%), preclinical DCA (PPV=96%) and clinical DCA (PPV=86%). Accuracy was lower for FC compared to IC for controls (PPV=88%), preclinical DCA (PPV=90%) and clinical DCA (PPV=82%). The MAE was low for all groups (<0.12s). Significant correlations were observed indicating that gait events were detected less accurately for individuals walking with a reduced cadence, longer stride duration, and increased gait variability (gait speed, stride length and duration).
Discussion and Conclusion: Accuracy for the single sensor approach was high and exceeded the threshold of 80% indicating that this approach may be used with confidence. Noticeable differences were observed in FC identification for clinical DCA, which may impact the calculation of gait outcomes. Additional refinements to optimize the algorithm should be considered to improve gait event detection accuracy.",
booktitle = "2024 International Congress for Ataxia Research (ICAR) London",
title = "{G}ait event detection in cerebellar ataxia: {A} single vs. multiple device approach",
year = "2024",
}