Tremor
Resting
tremor
• Occurs in body parts completely supported against gravity and relaxed
Action
•
Postural tremor
o When joint is held in static position against gravity
•
Kinetic tremor
o During voluntary muscle activation (i.e during activity)
•
Intention
o Worsens towards the end of goal directed movement
|
Activation state |
|
|
Rest |
PD – 90% ET 19% Not cerebellar |
|
Postural |
ET and Physiologic tremor - high PD 90% but often delayed/re-emergent Cerebellar to some extent |
|
Kinetic |
Hallmark of ET, larger amplitude than postural |
|
Intention |
Cerebellar very high ET 50% |
|
Variable |
Functional |
|
Distribution |
|
|
Hands |
PD (asymmetric) ET 95% bilateral Dystonic (when head involved) Functional – often spares fingers |
|
Legs |
PD Uncommon in ET |
|
Head |
ET 12-54% Dystonic PD 17% |
|
Frequency |
|
|
3-5Hz |
Cerebellar |
|
5-7Hz |
PD Structural lesions Cerebellar Dystonic |
|
6-12Hz |
Essential |
|
10-12Hz |
Physiologic ET |
|
Variable |
Functional |
|
Accompanying features |
|
|
Bradykinesia etc. |
PD |
|
Nystagmus, dysarthria, dysmetria |
Cerebellar |
|
Abnormal Posturing |
Dystonic |
|
Bizarre/inconsistent |
Functional |
|
None |
Physiologic ET |
|
|
|
Go to: Essential Tremor
References:
MJA 2018 Andre Loiselle Tremor: A simple four step approach to clinical assessment