Use the presence of continuous rippling or delayed relaxation to think about hyperexcitability rather than pure weakness alone. Myokymia should prompt a search for plexus injury, radiation history, or immune-mediated nerve dysfunction.

Myokymia causes continuous rippling or worm-like muscle activity on EMG; Radiation-induced plexopathy is a classic cause of myokymia; Anti-GM1 serology can support selected immune neuropathies; Slow contraction and delayed relaxation suggest a myotonic or hyperexcitable process; Localization depends on the pattern and the exposure history