Motor Unit Loss and Remodeling in Patients With Chronic Radiculopathy Using the EMG Filling Analysis

Area of Science:

• Neurology
• Biomedical Engineering
• Electromyography

Background:

• Motor unit (MU) potentials within EMG signals offer insights into muscle function during voluntary contractions.
• Chronic radiculopathy can lead to motor unit loss and subsequent muscle remodeling.

Purpose of the Study:

• To apply the EMG filling method for detecting motor unit loss and remodeling in patients with chronic radiculopathy.
• To differentiate EMG signal characteristics between radiculopathy patients and healthy controls.

Main Methods:

• Concentric needle EMG signals were recorded from the tibialis anterior during ramped voluntary contractions.
• EMG filling factor and amplitude were measured to analyze the EMG filling process.

Main Results:

• Radiculopathy patients exhibited a linear EMG filling curve, unlike the exponential curve in healthy controls.
• Healthy controls showed a significantly greater EMG envelope amplitude increase (6.1-fold) compared to patients (0.5-fold).
• EMG filling analysis identified motor unit loss and remodeling in 85% of radiculopathy patients.

Conclusions:

• EMG filling analysis is a rapid and accessible method for detecting motor unit loss in radiculopathy.
• This technique provides insights into motor unit remodeling and the types of motor units affected in neurogenic conditions.