Asymmetry Index in Muscle Activations

Area of Science:

• Biomechanics
• Neuroscience
• Orthopedics

Background:

• Gait asymmetry is commonly assessed via spatio-temporal or joint kinematics.
• Few studies utilize surface electromyography (sEMG) for gait asymmetry, and none focus on principal muscle activations.

Purpose of the Study:

• To define a robust index for quantitative assessment of muscle activation asymmetry during locomotion.
• To utilize principal muscle activations, derived from sEMG, for a more stable asymmetry index.

Main Methods:

• Analyzed sEMG signals using statistical gait analysis (SGA) and a clustering algorithm to extract principal muscle activations.
• Evaluated asymmetry in healthy individuals across age groups and in orthopedic and neurological patient populations.

Main Results:

• The developed asymmetry index demonstrated levels consistent with the known impact of various pathologies on gait muscle activation.
• The index showed successful differentiation of asymmetry in diverse patient groups including those with knee/hip replacements, bone tumors, cerebral palsy, and hydrocephalus.

Conclusions:

• The proposed index, based on principal muscle activations, provides a reliable and objective measure of gait asymmetry.
• This method holds significant clinical potential for assessing muscle activation asymmetry in locomotion across different patient populations.