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Postby Guest on November 26th, 2002, 3:10 pm

Asterix and everyone else

Here is the complete list of the emg questions from Tele EMG.
If you read carefully the info should be very reassuring.

I did my own little "risk" calculation in light of the famous 6.7% study.
5000 people in the US come down with als a year
out of these 5000, 359 ( 6.7%) are not diagnosed after there first neuro visit since they show fasc as their sole manifestation.
I am below 40 years of age and would be in a group of perhaps 60 people who are not diagnosed with als with twitching as their only symptom.
Since I am twitching for more than 6 month the number should be cut in half, since 50 % of the undiagnosed als patients experienced clinical symptoms by now. If the 6.7% study is true, out of 240.000.000 million people, 30 man under 40 have not been diagnosed with ALS due to the circumstances above. pretty slim :roll:. The number would be astronomically smaller if one would factor in a clean Emg at any point.
After all, the study should help us to overcome our fears.
Let me know your thoughts

Postby Guest on November 26th, 2002, 5:09 pm

sorry forget to add the link for teleemg:

Postby Arron on November 27th, 2002, 12:03 am

Guest, I hope your great post and well done calculations put people's fears at rest as to just how rare this stuff really is! Less than 30 people a year out of over 240 million people in the US. If my own calculations are correct, that makes it a 1 in 80,000,000 chance of having fasciculations only as a so called first symptom and as Guest put it, that is without the negative EMG factor which would most likely make it at least 50% less, or a 1 in 160,000,000 chance of that happening. That is a pretty astronomical number and with those kinds of odds, NO ONE should be worrying! Great post Guest!
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Postby Asterix on November 27th, 2002, 5:24 am

Hi Guest,

good to see your rational/statistical approach to this !
I did a similar risk analysis
some time ago. (have been twitching for 7.5 months now)
In addition I would factor in the
relative frequency of ALS vs. BFS
in the population (that's because of "conditional probability" we
should take the subset of twitchers
as basis population and not the whole general population), for which there are no exact numbers avaiable, though.
(All we can say is that BFS surely is much more common than ALS)
I could give you the details of
my little "study" per e-mail
(just send me a private message,
(don't want to bore anyone with
maths and stats here :)

Just one caveat about the interpretation of those statistics:
Note that above considerations do not take into account additional known facts/test results such as a clean EMG. Each additional known fact of each individual case will
alter the conditional
probabilities of this particular person. For example: sudden onset
of weakness will decrease the probability of BFS, whereas a clean neuro exam or EMG, of course, will greatly increase the chances of BFS to almost certainty.

So, once again I'd like to point out that this "risk analysis" is a rather academic/theoretical issue,
that only addresses the one hypothetical question: "If a person
of age x has been twitching for y months (without
any other sx/facts known about this
person), THEN what is the probability of this person having BFS vs. ALS)" It's somewhat analogue to the question "If I
have persistent coughing, is this
due to chronic bronchitis or lung cancer ?"

ok, enough of maths & stats now !
Go out now, live your life and forget about all the theorectical
risks ... :)
It's just not worth worrying about all the what-if's ..
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Joined: October 9th, 2002, 1:32 pm
Location: Europe

Postby tlotoxl on November 27th, 2002, 6:43 am

asterix - hahaha, sounds like an awesome statistical model you came up with. with the proper application of statistics, i'm quite confident that we can eliminate BFS within our lifetimes! ;)

i was thinking about working out some kind of model too, including (or rather excluding) from that 6.7% the number of people with BFS who independently developed ALS, but in the end just settled for 'very small chance'. still, i'd be curious to see what you came up with if you wouldn't mind emailing me at [email protected].
Selfless giver of time
Selfless giver of time
Posts: 223
Joined: August 16th, 2002, 8:17 am
Location: Fukuoka, Japan

Postby Asterix on November 27th, 2002, 11:10 am

people with BFS who independently developed ALS

haha: this one I neglected ;)

Hehehe, so finally I found some one who is even more obsessed with the statistical details than I am ;) ;)

But that's ok, sometimes the "nerdy" math stuff can be real fun and somehow distracting from the "real world" problems.
It can give you the nice illusion
to gain some control over the problems and risks you fear just by analyzing and calculating them.
I know, it's only an illusion, but sometimes a comforting one...

Just think of it as
a kind of "relaxation technique"
for nerds & techies


Posts: 47
Joined: October 9th, 2002, 1:32 pm
Location: Europe

Postby Guest on November 27th, 2002, 4:36 pm

I would like to add one more study. small but fine

Extensive, continuous fasciculations of the lower leg as an isolated symptom--a clinical and electromyography follow-up]
[Article in German]
Bischoff C, Klingelhofer J, Conrad B.
Neurologische Kinik der Technischen Universitat Munchen.
10 patients suffering from a widespread continuous fasciculation of the lower extremities without any other neurological signs and symptoms are presented. A follow up study of 6 of these patients could be done. The fasciculation potentials were polyphasic with changing shape from discharge to discharge and appeared irregularly in most of the muscles of the legs. In 5 patients no change of clinical and neurophysiological signs could be detected over the period of observation, whereas in one patient a sensory polyneuropathy was evident in course of time. The findings illustrate that a state of widespread continuous fasciculations without other signs and symptoms is not predicative for the development of a amyotrophic lateral sclerosis.
PMID: 2376393 [PubMed - indexed for MEDLINE]

Postby Guest on November 27th, 2002, 5:15 pm

The study above was done arround 1990 (before Mayo Study)



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