Idiopathic Limb Myokymia in Children: First Reported Cases Involving the Extensor Digitorum Brevis and Flexor
1Division of Pediatric Neurology, Department of Pediatrics, Medicalpoint Hospital, Gaziantep, Türkiye.
Annals of Indian Academy of Neurology
|May 22, 2026
Summary
Idiopathic limb myokymia, a rare condition of peripheral nerve hyperexcitability, can affect children
Area of Science:
- Neurology
- Clinical Electrophysiology
- Pediatric Neurology
Background:
- Idiopathic limb myokymia involves spontaneous motor unit discharges without a clear cause.
- It's linked to peripheral nerve hyperexcitability, often functional or ion channel related.
- Pediatric cases, especially in foot muscles, are uncommon.
Purpose of the Study:
- To report two pediatric cases of isolated distal lower limb myokymia.
- To highlight the clinical and electrophysiological features of this rare presentation.
- To emphasize the importance of recognizing and managing pediatric myokymia.
Main Methods:
- Case report of two pediatric patients with isolated distal lower limb myokymia.
- Needle electromyography (EMG) to confirm myokymic discharges.
- Comprehensive exclusion of secondary causes via laboratory and neuroimaging studies.
Main Results:
- Two pediatric patients presented with isolated distal lower limb myokymia.
- EMG confirmed typical myokymic discharges in intrinsic foot muscles.
- Both patients responded completely to carbamazepine treatment.
Conclusions:
- Focal intrinsic foot muscle myokymia can occur in children without autoimmune markers.
- It likely represents localized motor axon hyperexcitability.
- Characteristic EMG findings are crucial for diagnosis and differentiating from other movement disorders.
Keywords:
Idiopathic limb myokymiacarbamazepineextensor digitorum brevisflexor hallucis brevispediatricMore Related Videos
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