Analysis of muscle synergies in hand grasping through HD-EMG

Authors

  • Fernando Chillón Human Robotics Group, Universidad de Alicante
  • Lluís Bernat Human Robotics Group, Universidad de Alicante
  • Cristina Romero Human Robotics Group, Universidad de Alicante
  • Raquel Martínez Pérez Human Robotics Group, Universidad de Alicante
  • Andrés Úbeda Human Robotics Group, Universidad de Alicante

DOI:

https://doi.org/10.17979/ja-cea.2026.47.13839

Keywords:

Bio-signals analysis and interpretation, Developments in measurement, signal processing, Rehabilitation engineering and healthcare delivery, Control of voluntary movements, Assistive technology and rehabilitation engineering

Abstract

Muscle synergies describe how the central nervous system coordinates groups of muscles through common activation patterns, reducing the dimensionality of motor control. This work analyzes their extraction from 128-channel high-density electromyography (HD-EMG) recorded over the forearm during hand opening and closing tasks, using Non-Negative Matrix Factorization (NMF). Two synergies reconstructed muscle activity with a Variance Accounted For (VAF) above 97 %. The first, flexor-dominated, showed high inter-subject stability and was associated with grip generation and maintenance; the second, extensor, exhibited greater variability, consistent with individual strategies for stabilization and fine control during opening. Both activated in agreement with the biomechanical phases of grasping. This low-dimensional organization suggests applications as a biomarker of motor coordination in rehabilitation and as a reduced control space for more robust myoelectric interfaces.

References

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Published

2026-09-01

Issue

No. 47 (2026)

Section

Bioingeniería

License

Copyright (c) 2026 Fernando Chillon, Lluis Bernat, Cristina Romero, Raquel Martínez-Pérez, Andres Ubeda

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This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.