“Good Bye Pipe” these were the first words uttered by an 85 year old gentleman after a successful tremor surgery, enabling him to drink with his hands instead of straw…
Tremor is defined as a rhythmic involuntary movement of a body part, due to regular rhythmic muscle contractions. It is often categorized in three positions which are:
Static tremor occurs when a relaxed limb is fully supported at rest. This type of tremor is typically seen in patients of Parkinson’s disease
Postural tremor appears when a body part is maintained in a fixed position. It and may also persist during movement. This tremor is seen in patients of essential tremors/post stroke tremors etc.
Intention or action tremor occurs specifically during active voluntary movement of a body part. If the amplitude of such an action tremor increases as goal-directed movement approaches the target. This is seen in patients of spin cerebellar ataxia, multiple sclerosis, etc.
Psychogenic tremors are generally rare and typically are of sudden onset with a variable but rarely remitting clinical course and typically affect the trunk or limb with standing and/or using the limb respectively.
The frequency, amplitude and severity of the tremor may vary from patient to patient.
| REST TREMORS | ACTION TREMORS | ||
|---|---|---|---|
| POSTURAL | KINETIC | MISCELLANEOUS | |
| Pariksonian ET variants Midbrain lesions Myorhythmia | Physiologic Enhanced Physiologic (Stress, drugs, endocorine) ET Orthostatic PD (reemergent) Dystonia Cerebellar Neuropathic | Cerebellar Lession as in MS Stroke, Wilson Disease Midbrain Task Specific | Idiopathic Psychogenic Other Involuntary Movements like Myoclonus Fasciculations Asterixis, Clonus |
There are various causes for tremor. The diagnosis of various kinds of tremors is based on the clinical spectrum and radiological imaging.
Most Common:
Less Common:
Midbrain or rubral
Essential tremor (ET) is one of the most common tremor disorders.
Parkinsonian Tremor
Tremors of multiple sclerosis are much coarser and have larger amplitudes. The post stroke tremors and tremors due to other cerebral insults are less frequent and hence require specialist evaluation
Pathophysiology of Tremors
Tremor Rating
Treatment for tremor entirely depends on two factors: one is its cause and the second is the amount of disability that it creates. For e.g.. A mild tremor in a CEO of a company or a surgeon can be significantly disabling, whereas same may not be a problem to manual labor.
General principles
Non-pharmacologic
Pharmacologic
Voice, head
Surgical Treatment:
Thalamotomy – Deep brain stimulation is an effective treatment and is most useful to treat bilateral tremors as bilateral thalamotomy is contraindicated. DBS is also used for difficult to treat treatment disorders like Spinocerebellar ataxia, Multiple sclerosis and post stroke tremors.