EDX-07 · Plexopathy

Plexopathy. Part of the Electrodiagnostics series of the Reflex PM&R Board Review podcast. Audio correction: In the audio: A tumor crushes or infiltrates the axon, so there is no unstable membrane left to fire. — Correct: Myokymia is uncommon in tumor plexopathy, not impossible. The same passage gives the right figures seconds earlier: myokymic discharges in 50 to 70 percent of radiation cases and about 4 percent of tumor cases. Malignant infiltration does not abolish every demyelinated, ectopically firing segment, and recurrence can sit inside a previously irradiated field, so myokymia shifts the odds toward radiation without excluding tumor. Image the plexus with contrast whatever the needle examination shows. The written chapter is correct. Full correction register: https://www.reflexpmr.com/errata. The full companion chapter and a linked board-style Q-bank set for this topic are at https://www.reflexpmr.com/read/EDX-07.