Movement Disorders Flashcards
What is the difference between hypo and hyperkinetic movement disorders?
Hypo = too little movement, hyper = too much movement
What are some examples of hypokinetic movement disorders?
Parkinson’s disease and akinetic rigid syndrome
What are some examples of symptoms of hyperkinetic movement disorders?
Tics, tremore, myoclonus, dystonia, chorea
Describe the features of primary hyperkinetic movement disorders?
Usually no underlying structural brain lesion, non-progressive and often inherited
What is the defining feature of a secondary hyperkinetic movement disorder?
Presence of a precipitating factor i.e. brain injury, infection, toxin
Describe the features of heredo-degenerative hyperkinetic movement disorders?
Typically late onset and progressive
Describe the features of psychogenic movement disorders?
Unusual physical features with psychological disturbance
What is another term used to describe hyperkinetic movement disorders?
Dyskinesias
What is the physiological cause for a tremor?
Alternate activation of agonist and antagonist muscles
What are the main causes of a resting tremor?
Parkinson’s disease/Parkinsonism, psychogenic
What is the main cause of a postural tremor?
Essential tremor
What are the main causes of a kinetic tremor?
Cerebellar disease and Wilson’s disease
How should patients presenting with a tremor be examined?
At rest, on posture and while moving. They should also be asked to write something and to draw a spiral, as well as a complete neurological exam
What are some investigations you should do on a young person presenting with a tremor or dystonia?
TFTs and copper/ceruloplasmin levels
Describe an essential tremor?
A symmetrical postural or kinetic tremor with high frequency
What are the core criteria of essential tremor?
Bilateral action tremor of the hands and forearms / absence of other neurological signs / may have isolated head tremor with no dystonia
What are some secondary criteria of essential tremor?
Long duration (> 3 years), positive Fx, beneficial response to alcohol
Essential tremor is commonly inherited - what pattern does it follow? What is its mean age of onset?
Autosomal dominant / 15
What are the first line treatments for essential tremor?
Propranolol and primidone
What is a last line treatment for patients severely affected by essential tremor?
Deep brain stimulation of the ventralis intermedius nucleus
What are tics?
Involuntary, stereotyped movements or vocalisations
Are tics suppressible?
Yes, but this creates internal tension within the patient
Describe how a patient with a tic disorder may feel whilst trying to suppress a tic?
A growing feeling of anxiety and discomfort
When do primary tic disorders almost always start?
In childhood
What investigation is usually done for a tic disorder?
Usually none, but should be guided by the history
What are some things that tic disorders can occur secondary to?
Neurodegenerative disorders, developmental syndromes, structural abnormalities, infection, drugs/toxins
Patients with Tourette’s syndrome often also have what else?
Obsessive compulsive behaviours and decreased impulse control
Which gender is more commonly affected with Tourette’s syndrome?
Males (4: 1)
Though no candidate gene has been identified, Tourette’s syndrome is often inherited. What is the pattern of this?
Autosomal dominant
With regards to the tics themselves, what is the criteria for Tourette’s syndrome?
Multiple motor tics and one or more vocal tics must be present
How often must the tics occur to be diagnosed with Tourette’s syndrome?
Many times a day, nearly every day OR intermittently for more than 1 year with no longer than 3 months tic free
To be diagnosed with Tourette’s syndrome, what is important about the age of onset?
Has to be aged < 18 at the time of onset
What are some treatment options for Tourette’s syndrome?
Clonidine/tetrabenazine and CBT
What is chorea?
Brief, irregular, purposeless movements that flit and flow from one body part to another
How will patients with chorea appear?
Constantly restless and fidgitey
What are some groups of investigations that may be done for patients presenting with chorea?
Brain imaging, autoantibodies, copper studies, genetic testing
What is the ideal treatment of chorea? What can be used as symptomatic treatment?
Treat the underlying cause / tetrabenazine, or dopamine receptor blocking drugs
How is Huntington’s disease inherited?
Autosomal dominant
What are the two characteristic features of Huntington’s disease?
Behavioural disturbance (dementia) and movement disorder (usually chorea)
When is the typical onset of Huntington’s disease?
In the 4th decade
What is the genetic cause for Huntington’s disease?
CAG trinucleotide repeats affecting the Huntingtin gene on chromosome 4
The number of CAG repeats has what effect on Huntington’s disease prognosis?
The more repeats, the earlier onset and greater severity
How many CAG repeats are needed to diagnose Huntington’s?
36
What test is used to confirm a diagnosis of Huntington’s? What investigation can be done while this is awaited?
Genetic testing / MRI brain
What is myoclonus?
Brief, electric shock like jerks
What are some examples of common and normal forms of myoclonus?
Hiccups, and hypnic jerks (when falling asleep)
What causes myoclonus?
Brief activation of a group of muscles leading to a jerk of the affected body part
How is negative myoclonus produced? Give an example?
Temporary cessation of muscle activity / liver flap
Investigation of myoclonus is guided by presentation but what can be used to characterise it?
Electrophysiological tests
Treatment of myoclonus is often symptomatic and involves what? What is the side effect of this?
Using multiple drugs / sedation
When does juvenile myoclonic epilepsy tend to begin? What does it begin with?
Teenage years / myoclonic jerks and seizures
What are some typical precipitants of myoclonic jerks and seizures in juvenile myoclonic epilepsy?
Sleep deprivation and alcohol
When are symptoms of juvenile myoclonic epilepsy typically worst?
In the morning
What are some effective treatments for juvenile myoclonic epilepsy? What treatment should not be used as it can exacerbate the condition?
Sodium valproate or leviteracitam / carbamazepine
What is dystonia?
Involuntary muscle spasms which lead to sustained abnormal postures of the affected body part
In dystonia, typically the abnormal posture is not fixed. What does this lead to?
Slow, writhing movements (athetosis)
Dystonia can often be associated with what affecting the same body part?
Tremor
Dystonia is often improved with what? And made worse by what?
Sensory tricks / particular positions or tasks
Dystonia is generally classified by what? Describe the categories?
Age of onset, early onset aged < 26 and late onset aged > 26
What is primary dystonia?
Dystonia +/- tremor are the only features
What are dystonia plus syndromes?
Other features apart from only dystonia and tremor may occur, but there is no secondary cause or neurodegeneration
What is paroxysmal dystonia?
Episodic attacks, with no clinical signs between attacks
Where in the body is affected by each of these types of dystonia: a) focal? b) segmental? c) hemibody? d) multifocal? e) generalised?
a) single body region b) continuous body region c) ipsilateral arm and leg d) 2 non-contiguous body parts e) whole body
What can play an important role in causing focal dystonia?
Botox
What is the treatment for dystonia?
Symptomatic, if at all
When do primary young onset dystonias typically occur?
Late childhood/early teends
Describe the typical onset of a primary young onset dystonia?
Limb onset with the spread of symptoms over months to two years
50-60% of patients with primary young onset dystonias will have a mutation where?
DYT1 gene on chromosome 9
What is the inheritance pattern of primary young onset dystonias?
Autosomal dominant
What are some differentials of primary young onset dystonias?
Dopa-responsive dystonia (always do a Levodopa trial) or a young onset of other degenerative disease
