Surface electromyography and mechanomyography recording: a new differential composite probe

Area of Science:

• Biomedical Engineering
• Neuroscience
• Biomechanics

Background:

• Electromyography (EMG) and mechanomyography (MMG) are crucial for assessing muscle function.
• Differential amplification is a standard technique to enhance signal-to-noise ratio in EMG.
• Existing MMG probes may be limited in artifact suppression and simultaneous recording capabilities.

Purpose of the Study:

• To develop and evaluate a novel composite surface probe for simultaneous differential mechanomyographic (MMG) and electromyographic (EMG) signal recording.
• To assess the efficacy of differential amplification in improving MMG signal quality and reducing artifacts.
• To compare the performance of the new differential probe with a non-differential MMG probe.

Main Methods:

• A composite probe was designed with integrated electrodes for EMG and piezo-electric membranes for MMG.
• The probe incorporated built-in fixed-gain differential amplifiers for both EMG and MMG signals.
• Burst muscular activity was recorded using both the novel differential probe and a conventional non-differential MMG probe.
• Power spectrum analysis was employed to quantify signal-to-noise ratio and artifact suppression.

Main Results:

• Differential amplification significantly improved the signal-to-noise ratio for MMG recordings.
• Artifacts of non-muscular origin were significantly suppressed by the differential probe, with power differences exceeding 90%.
• The composite probe enabled simultaneous differential recording of both MMG and EMG signals from the same muscle site.

Conclusions:

• The developed composite probe allows for efficient and simultaneous differential recording of MMG and EMG signals.
• Differential amplification is highly effective in enhancing MMG signal quality and suppressing artifacts.
• This novel probe shows potential utility in the study of muscle fatigue and neuromuscular diseases.