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F-wave motor unit numbers do not change in diabetic polyneuropathy: does it indicate a pathophysiologic mechanism for
Isil Yazıcı Gencdal1, Nermin Gorkem Sirin1, Tugrul Artug2
1Departments of Neurology and Clinical Neurophysiology, Faculty of Medicine, Istanbul University, Istanbul, Turkey.
Neurological Research
|March 5, 2025
Summary
Repeater F-wave parameters may detect axon loss in diabetic polyneuropathy, but F-wave motor unit number estimation (F-MUNE) did not show significant differences between patients and controls.
Area of Science:
- Neuroscience
- Clinical Electrophysiology
- Diabetology
Background:
- Motor unit number estimation (MUNE) methods, including F-wave MUNE (F-MUNE), are utilized to identify axonal loss in polyneuropathies.
- Diabetic polyneuropathy is a common complication of type 2 diabetes mellitus (DM).
Purpose of the Study:
- To assess axonal loss in type 2 diabetic polyneuropathy using repeater F-wave parameters and F-MUNE.
- To compare F-wave parameters and F-MUNE between diabetic patients and healthy controls.
Main Methods:
- Recorded 90 F-waves with supramaximal and 300 with submaximal ulnar nerve stimulation in 49 diabetic patients and 24 controls.
- Calculated F-MUNE values using automated software with submaximal stimulation.
- Analyzed abductor digiti minimi muscle responses.
Main Results:
- Ulnar repeater F-wave index and repeater neuron index were significantly higher in diabetic patients.
- F-wave amplitudes were reduced in diabetic patients compared to controls.
- F-MUNE values were similar between diabetic patients and controls.
Conclusions:
- Repeater F-wave parameters may indicate axon loss in diabetic polyneuropathy.
- F-MUNE may not be sensitive enough to detect axonal loss in diabetic polyneuropathy due to potential confounding factors like length-dependence and low-amplitude F-waves.
Keywords:
F-waveF-wave amplitudeMotor unit number estimationdiabetes mellituspolyneuropathyrepeater F-waveMore Related Videos
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