Clonus vs. Tremors

[RooRoo]

What is the difference between clonus and tremors? I'm reduced to using a plastic wine glass!

 

[IhavePLS]

Hi RooRoo, from what I have seen/ experienced, I think most people would say that tremors are more fine, while clonus is much more violent. In other words, you can't miss someone with clonus -- you could miss seeing someone's tremor.

I assume tremors occur anywhere in the body -- while clonus locates itself in the knees, ankles, and forearms.

 

[Bad Balance]

Yes,
Clonus is usually a one time jerk reaction while tremors are continued shaking
I always get them when I yawn or sit on the wrong part of my hamstring on the edge of the bed

 

[MaxEidswick]

>I'm reduced to using a plastic wine glass

Me too!

 

[bigmark1954]

I have clonus in my ankles and mostly notice it when I am on the exercise bike. I can kind of control it by maintaining certain angles of my ankles on the pedals. Clonus is different from tremors in that it actually moves the affected appendage up and down in a spastic dynamic. I also have fasics and tremors that don't move the body part.

 

[BrianD]

Yes,
Clonus is usually a one time jerk reaction

I have to very respectively disagree. Clonus is a rhythmic repetitive motion. For example, having 5 or more "beats" of ankle clonus is the criteria for being labeled as pathological.

There are some examples on you tube.

 

[bigmark1954]

I have to very respectively disagree. Clonus is a rhythmic repetitive motion. For example, having 5 or more "beats" of ankle clonus is the criteria for being labeled as pathological.

There are some examples on you tube.

True That!

 

[IhavePLS]

Hi Brian, I believe that Jerry (Bad Balance) is suggesting that clonus is activated by some external force, e.g., tapping of the knees or ankles. In this sense, it is a "one time jerk reaction" as Jerry suggests.

Tremor exists irrespective of any such external influence or activation. It is also rhythmic in nature.

I don't mean to speak for Jerry -- but I believe that is the distinction being made here (please correct me if I'm mistaken).

Regardless of the difference between them, most people "know" a tremor when they see it -- in contrast, most people would not be familiar at all with clonus.

Thanks!

Mike

 

[Kosmoskatten]

I will try to describe this without sounding utterly confusing. This is at least what I have learned are the differences;

- Clonus are a series of rythmic and monophasic contractions and relaxations of a group of muscles. Monophasic means they are unidirectional.
- Tremors are less rythmic and repetitive, and they are always diphasic, i.e bidirectional.

I understand these are medical terms, so I think the easiest way of putting it is that clonus is much more repetitive.

- The "jerk" that is described in the thread I would label myoclonus which is another thing. It is a very rapid contraction, almost like a shock. Myoclonus is usually irregular in rythm, and can be benign. To further complicate it there is also polymyoclonus that can look as a more violent form of clonus, and it can occur anywhere, but to differentiate it from "regular" clonus it is always irregular in rythm.

A lot of people have the sleep form of myoclonus, called hypnic jerks, which is the "jumping" you can sometimes feel when you are about to fall asleep.

 

[vickim]

Are tremors also when you try to hold your arm up at shoulder level (like holding a blow dryer) and it starts to shake?

 

[Nikki J]

It can look similar but I don't think you would classify shaking from overexertion as tremor. Everyone shakes when their muscles are under strain. It is just that people have different thresholds Think of a weightlifter lifting his/ her max when they are tired.

 

[vickim]

Thanks Nikki, although it makes me sad that a blow dryer being held up could be my "max". My goodness these diseases are really crappy.

 

[Nikki J]

I hear you Vicki! It stinks. When I had my neuro exam he had me hold a plastic dixie cup of water up and told me it was a strength test! Yikes! Fortunately I passed!

 

[MaxEidswick]

>Think of a weightlifter lifting his/ her max when they are tired.

if you could lift this max (me) you would be considered very strong

 

[Kosmoskatten]

From what I have learned when it comes to tremor there are many different types of action and postural tremors, one of them being exertion tremor. But as Nicki says, there is also the case of the muscle being pushed beyond it's capability, which also causes shaking.

It is impossible to tell over the forum what is the case for each individual, but a neurologist can of course test to see if its action tremor or if it is weakness exertion. Action tremor is for instance quite common in MS, but I have seen it in patients with various other neurological issues. I have some postural, for instance sometimes when I keep my arms outstretched in air I get tremor.