Tremor is movement of a body part (often hands, occasionally legs, neck or face) which is not under voluntary control. Moving can also be affected, such as slowness of difficulty.
Essential tremor
Essential tremor generally presents as a rhythmic tremor (4–12 Hz) that is present only when the affected muscle is exerting effort (in other words, it is not present at rest). Any sort of physical or mental stress will tend to make the tremor worse, often creating the false impression that the tremor is of psychosomatic origin. Tremor intensity can worsen in response to fatigue, strong emotions, low blood sugar, cold, caffeine, lithium salts, some antidepressants or other factors. It is typical for the tremor to worsen in “performance” situations, such as when making out a check at a cashier.
It is generally treated with medications, such as beta-blockers.
Parkinson’s disease
Parkinson’s disease is a progressive neuro-degenrative disease associated with several key manifestations:
- Tremor – unlike essential tremor, this is a resting tremor (occasionally affects during load bearing)
- Slowness of movement (bradykinesia) and stiffness (rigidity), making walking slower and shuffling and all movements slow and at times difficult to initiate
- Cognitive dysfunction, such as executive dysfunction (difficulty with planning and abstract thought), impaired memory and slowness of processing speed.
- Autonomic dysfunction causing postural blood pressure drops, urinary incontinence and altered sexual function
Parkinson’s is treatable with medication which controls the movement abnormalities in particular, as well as surgery (deep brain stimulation or DBS) in selected patients.
DBS Therapy for Parkinson’s control helps reduce some of the symptoms of Parkinson’s disease and is used in conjunction with medication. Electrical stimulation is delivered to targeted areas on both sides of the brain to help relieve symptoms on both sides of the body. You may be a candidate for this therapy if your symptoms respond to levodopa, but levodopa and/or other medications have become less effective than before or with problems such as wearing off, freezing or extra movements such as dyskinesia.
Clinical evidence has shown that when added to medication DBS:
- Provides 5 additional hours of good movement control each day compared to medication alone.
- Improves quality of life more than medications alone and makes routine daily activities easier.
- Significantly reduces medication use, which may mean fewer medication-related side effects.
Other Disorders
Other disorders that need to be excluded include thyroid problems and consideration of medication side effects as well. In addition, there is a family of disorders, called Parkinson’s Plus, which are similar to Parkinson’s disease, but associated with somewhat different symptoms and long-term outlook (prognosis).
Treating Tremor with Botox
Botulinum toxin can be used to treat different types of tremor , including dystonic tremor, essential tremor and Parkinsonian tremor. Of utmost importance is examination, to determine the muscles involved in the tremor and this is a very specialised skill that Dr Duma now brings to East Neurology.
For example, a dystonic tremor of the upper limb may be characterised as wrist supination and pronation (back and forth movement of the wrist). In this case, to treat the tremor with botulinum toxin, the supinator and pronator muscles are targeted with EMG (needle muscle test), during which tremor muscle activity can often be heard, following which botulinum toxin is injected.
To avoid muscle weakness, small doses are used initially and can be increased at subsequent injection visits depending on previous response.
The aim of botulinum toxin is to provide an improvement in the intensity of the tremor but it needs to be repeated on average every 3 months, and so is not a cure.