What does polyphasic motor units mean?

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New member
Feb 17, 2008
I am having mild left foot weakness and general fatigue and burning especially in my left leg.I had an Emg test and it showed long duration polyphasic motor unit potentials in my legs (mainly left). neuros told me that it doesn't show ALS after examining me but I am so scared about the possibility.I would really appreciate any input.thank you.
join the club...Large MUPs...basically the nerves send signals to the muscle, but sometimes interference happens and more signal has to be sent to activate muscles... you don't get them unless you have some sort of nerve damage so you should ask them why you have this and what can be done.
Thank you for yor reply.

This site refers my findings as a result of MND. I guess i will have to wait and see what happens. No clinical weakness or atrophy by now. Just aching, burning type muscles (esp. lef leg) I wonder if someone had the same findings and results or have more info on the subject. The uncertainity is killing me..
it can mean a # of things, it depends on the company they keep.
ask your nueroligist.
I think it it is a sign of renervation (but don't quote me on that)
hang in there....
google polyphasic units and see what you get as a meaning.
i have all those symptoms and atrophy and i DO NOT HAVE ALS...you can have cramps, exercise intolerance, weakness, random constant twitching, burning, numbness and tingling with peripheral neuropathy or any injury to the nerves...you don't necessarily have to have slow SNAPS to have it (abnormal sensory nerve conduction) it can show up as a motor neuron dysfunction...i totally understand your worry as i have been living this nightmare for four months, please talk to your neuro...ask him/her point blank if you have a motor neuron disease...and if he says no, then ask, WHAT IS IT?

ALS is extremely rare...there are MANY things that can cause these symptoms including hernias, sublixations in your spine...doctors just don't seem to understand that waiting for answers is cruel punishment to patients (patience)...but, sometimes that's all we can do is wait it out...in the meanwhile, i asked for physical therapy and medications to reduce my ridiculous pain...it helped me and maybe good for you?...good luck
thank you very much for your reply..

i wonder if there would be any other thoughts?
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