For all the anxious twitchers with clean EMG...

[JulieBS]

Hello!

After reading a lot, searching a lot, I realized something that definitely reassured me. I thought it might help other people who are anxious ... (Sorry for my english, it's not my first langage )

ALS combines problems of upper and lower motor neurons. Each pathway has its own symptoms:

Upper motor neurons :
- weakness
- hyperactive reflexes
- increased muscle tone
- spasticity
- rigidity
- minimal paralysis of voluntary movement
- tremor

Lower motor neurons :
- loss of muscle tone
- ipsilateral (same side) weakness of individual muscles
- flaccidity
- atrophy
- weak or absent deep tendon plantar reflexes and abdominal reflexes
- fasciculations (muscle twitching).


In some rare cases, the patient first presents problems only at the upper motor neurons pathway. It's in this case that you can have a clean EMG, before developing the disease.

So for all the people who, like me, have anxieties about fasciculations despite clean EMG, just keep in mind that fasciculations are the consequence of the "lower motor neuron disease" part of ALS. So, if it was ALS, the EMG would definitly not be good.

Feel free to correct me, but I think I might help some people ;-)

 

[KarenNWendyn]

That’s mostly correct. UMN symptoms are more likely to include stiffness and incoordination rather than weakness. Weakness per se is a LMN sign. I would also take tremor off the list. The term “tremor” means different things to different people, but true tremors are generally not associated with motor neuron disease.

You also list weak or absent reflexes as a lower motor neuron sign. That is incorrect. LMN doesn’t affect the reflexes. UMN can increase them. ALS is a combined LMN/ UMN disease, so the reflexes are generally hyper. Occasionally they start out normal but increase over time as the disease progresses.

The other reality is that people with PLS, which is theoretically a pure UMN disease, will usually have some abnormalities on their EMGs and physical exam changes beyond hyperreflexia and clonus (one of our moderators, Shiftkicker, has explained this in a number of her posts here).

I mention this because hyperreflexia itself can be a normal variant. We see a lot of anxious people posting with twitching, hyperreflexia, and clean EMGs who do not have motor neuron disease.

The other thing that’s important when diagnosing ALS is that clinical findings are progressive.

 

[Nikki J]

Weakness is more a lower motor neuron sign but umn disease can cause weakness which we see in some of our people who start with PLS and normal EMGs. They will also have other findings on Clinical exam.

As we say normal emg and normal exam taken together exclude ALS/ MND

 

[Clearwater AL]

Julie, the statement you wrote…

(“Like me, have anxieties about fasciculations despite clean EMG, just keep in mind that
fasciculations are the consequence of the "lower motor neuron disease" part of ALS…”)...

is misleading if not totally inaccurate… unless I misunderstood your intent.

Someone may correct me if I am wrong but… fasciculations are not a part of
the diagnosis of PLS. Someone with PLS having fasciculations is more so
related to anxiety.

With PLS the muscles are receiving weak or fluttered signals… unlike ALS
where the muscles are dying because of no signal from the brain and spinal cord.
My words, trying to regenerate… not using all the medical terminology better
described by others.

Nikki, Laurie, Karen, Fiona… ?

Note: I can't compose on the fly like I used to. If do I post something that is
somewhat structured with terminology it's because I wrote it on Word first where
it takes 30 minutes or an hour to do it. Above is...

 

[Nikki J]

What I believe Julie is saying is that if fasciculations are a part of motor neuron disease rather than being simply benign as they usually are they are part of the lower motor neuron disease process. When one has lower motor neuron disease the Emg will show it.

This is consistent with what you said Al

To reiterate a normal EMG and a normal clinical exam ( brisk/ hyper reflexes without other findings fall into the normal range) rule out MND.

Abnormalities may occur in both EMG and clinical exam and still point to something else.

It is up to the doctor to determine the significance of findings and what follow up if any is needed

I am closing this thread as I believe the point has been made