Polio Survivors Having a “Normal” EMG
Dr. Bruno’s Original Post: This article helps to explain “Normal” EMG’s in Polio Survivors.
How To Interpret Normal Electromyographic Findings In Patients With An Alleged History Of Polio.
By Arne Sandberg and Erik Stalberg
“In some patients with a history of polio, the electromyography is normal, not showing the typical neurogenic signs. The aim of this study was to explain the normal findings in electromyography, especially in paralytic polio.
Design: Retrospective study. Subjects/methods: Concentric needle electromyography, macro electromyography (including single fibre electromyography) and neurography were performed in various combinations in 688 patients with an alleged history of polio.
Results: Thirty-five patients with paralytic polio had normal or minimally abnormal neurophysiology. In 6 patients the diagnosis of polio was rejected and was instead found to be other diagnoses. Three patients had a very atypical history. Of the 26 with possible paralytic polio, 17 showed a strong suspicion of previous paralytic polio without any neurophysiological signs of degeneration of the anterior horn cells.
Conclusion: If neurophysiological findings are normal inpatients with a history of polio, the original diagnosis may be incorrect. However, the absence of electromyography changes does not entirely exclude a previous history of polio with transient functional loss WITHOUT degeneration of anterior horn cells that are vulnerable for later functional impairment.”
J Rehabil Med 2004; 36: 169–176 https://pubmed.ncbi.nlm.nih.gov/15370733/
Additional Post: Does this explain why the EMG was negative on my arms and positive on my legs?
Dr. Bruno’s Response: That’s very likely.