Abnormal EMG?

[serraaleix]

Hello everyone,

I would like to please ask for your opinion regarding the interpretation of some EMG results. For almost three months now, I have been experiencing some concerning symptoms: fasciculations, stiffness, mild tingling in my right leg and arm, and mild weakness. The tingling and weakness do not seem to have worsened, but the fasciculations and stiffness have increased.

In any case, just a few days after the onset of my symptoms, I went to a neurologist, and they performed an EMG and a nerve conduction study. The study came out normal, and the EMG only detected a mild neurogenic pattern in both vastus lateralis muscles (MUAP AMP +1 and reduced recruitment pattern). It seemed like a very thorough and professional examination, so I felt very reassured.

However, since then, the fasciculations and stiffness have continued to increase, so given how early the first EMG was performed, I was advised to repeat it. At this point, I was convinced that I had Isaacs' Syndrome, as I felt like I was experiencing myokymia in my legs, and additionally, exercise worsened my symptoms, while benzodiazepines alleviated them (they were prescribed to me at the beginning, as my symptoms caused a lot of anxiety).

In any case, I had a second EMG yesterday, which was much shorter than the first one and involved fewer tasks (moving my limbs, exerting force, etc.). The neurophysiologist gave me the results but did not explain them to me, so now I have to wait until next week to see the neurologist. The EMG seems significantly more “abnormal” than the previous one, but I am not sure why. Could you please give me your opinion? Thank you very much in advance.

The translated comments from the neurophysiologist are:
"Signs of mild-to-moderate acute denervation, with the presence of some fasciculation-like potentials, at the level of the gastrocnemius bilaterally. No loss of motor units. Signs of denervation, without fasciculations, are also observed in the right C7 myotome."

 

[lgelb]

This EMG does not suggest ALS at all. It shows acute but not chronic denervation (both are required to even think of ALS). When you see the neurologist, they can explain the cause most applicable to your situation and what can be done. Physio and/or attention to your position in certain activities may be recommended.

Whether an EMG looks abnormal (but not sinister) can depend on which muscles were sampled, which is the option of the examiner based on your previous study. It is like looking for anything else -- sometimes it pays to keep going back to the same place (muscles) for comparison and sometimes to move on to different ones.

 

[serraaleix]

Thank you very much, Igelb! I will return on the 20th with my neurologist’s feedback. It might be interesting for people who are in the same situation as me.

Regarding the two EMGs, they were performed by two different institutions and two different professionals. This is because, since my symptoms began, I have been consulting both the public and private healthcare systems (it's a bit complicated to explain how the healthcare system works in Spain). In any case, in the private system, I had the EMG just two weeks after my symptoms started, whereas in the public system, it was done after two months. They do not share data between them, and the fact that the neurophysiologist who performed the first EMG concluded that the alterations in both vastus lateralis muscles were likely due to hypertrophy from the extreme physical exertion I did in the three weeks prior to the test—specifically with exercises targeting those muscles—led me to not consider it relevant to mention it to the second neurophysiologist. I didn’t think it was important at the time, but perhaps I should have brought it up.

In any case, on the 20th, I will share my neurologist’s feedback, to whom I will present my full medical history.

 

[serraaleix]

Hi!

Just a quick update. I already went to the neurologist. He asked a lot about my family history regarding neuromuscular diseases. Since I’m young (30 years old), I imagine he wanted to check if I could be at risk for familial ALS. Then, he performed a basic neurological examination: walking on tiptoes, on heels, one foot in front of the other, reflexes (no hyperreflexia or clonus).

Regarding the EMG, he said he didn’t trust the neurophysiologist’s work and suggested that she might have mistaken fasciculations for denervation (I found him a bit arrogant on this point, to be honest). I’m not sure how likely it is for a neurophysiologist to confuse fasciculations or myokymia with PSWs and fibrillations.

In any case, he has ordered a full spinal MRI (I recently had a brain MRI that came out fine) and an extensive blood test.