High-Density Electromyography Provides Improved Understanding of Muscle Function for Those With Amputation

Area of Science:

• Biomedical Engineering
• Rehabilitation Science
• Neuroscience

Background:

• Transtibial amputation significantly impacts daily living and prosthetic control.
• Myoelectric prostheses utilize residual limb muscle electrical activity for control.
• Limited research characterizes surface electromyography (sEMG) changes in upper leg muscles post-amputation.

Purpose of the Study:

• To investigate quadriceps muscle activity using high-density surface electromyography (HDsEMG) during isokinetic knee extensions.
• To compare muscle activation and heterogeneity between the intact and amputated limbs of a transtibial amputee.
• To explore the potential of HDsEMG for understanding muscle behavior in clinical populations.

Main Methods:

• Collected HDsEMG data from the quadriceps of the dominant leg in 14 healthy males and one transtibial amputee.
• Recorded signals during slow, moderate, and fast isokinetic knee extensions.
• Analyzed spatial activation maps and features to assess muscle activation and heterogeneity.

Main Results:

• Significant differences were observed in muscle activation and heterogeneity between the intact and amputated limbs of the clinical participant.
• HDsEMG enabled detailed spatial mapping of muscle activity.
• Findings suggest altered muscle behavior in the residual limb post-amputation.

Conclusions:

• HDsEMG is a valuable tool for characterizing muscle changes in transtibial amputees.
• Differences in muscle activation and heterogeneity warrant further investigation.
• Understanding these alterations can inform improved prosthetic design and rehabilitation protocols.