Hyperkinetic movement disorders ppt

Hyperkinetic Movement Disorder

Hyperkinetic movement disorders are characterized by involuntary movements that may occur in isolation or in combination .
It consist of tremor , dystonia , chorea , athetosis , myoclonus , tic and hemiballismus.

A: Tremor

It is abnormal involuntary rhythmic oscillation of body part due to intermittent contraction of agonist and antagonist muscles
it can be prominent at rest (rest tremor) like Parkinson disease or at assuming posture (postural tremor) like essential tremor or on actively reaching a target (kinetic tremor) like cerebellar disease.

Postural Termor

This type of tremor occurs mainly during action . The causes of this type of tremor are:
1-Enhaced physiological tremor. it is mild , high frequency tremor occurs in about 10 percent of normal population mainly due to stress, anxiety , alcoholism ,thyrotoxicosis , drugs like beta 2 agonist ,valproate ,and lithium. It affects the hand only. It need no treatment just treat underlying cause sometimes need small dose of beta blocker.

2-Benign essential tremor. It is benign, autosomal dominant (familial) occurs mainly during action like drinking a cup of water or stress ,it begin sometimes at childhood and increase by age to become very clear at 5th to7th decade of life ,it is of a high frequency affecting mainly the upper limb symmetrically then after years affecting the lower limbs , head in the form of (NO NO) , jaw and voice. Very small percent of this tremor associated with rest tremor , but can be differentiated from Parkinson disease by absence of bradykinesia ,rigidity and postural instability.

Treatment

 Propranolol 20-80mg daily in divided doses
Primidon started at small dose 12.5 mg then gradually increase the dose to (125 -250) 3 times daily , side effect of this drug is sedation and vomiting.
Other treatment topiramate ,gabapentin ,and botulinum toxin .


Hand tremor responds to medical treatment unlike head tremor which has poor response to medical therapy . Resistant cases treated by surgery by deep brain stimulation to ventromedial nucleus of thalamus.

Other causes of postural tremor are Wilson (wing beat tremor) ,neuropathy, fragil x syndrome, dystonic tremor and some cases of Parkinson disease.

DYSTONIA

Dystonia is a disorder characterized by sustained or repetitive involuntary muscle contractions frequently associated with twisting or repetitive movements and abnormal postures.
Dystonia can range from minor contractions in an individual muscle group to severe and disabling involvement of multiple muscle groups.
-Dystonia is often brought out by voluntary movements (action dystonia) and can become sustained and extend to involve other body regions.
- It can be aggravated by stress and fatigue, and attenuated by relaxation and sensory tricks such as touching the affected body part .

- Dystonia can be classified according to :

1-age of onset (childhood vs adult).
2-Distribution (focal, multifocal, segmental, or generalized),
3-Etiology (primary or secondary).

1-primary dystonia

A-Generalized Dystonia
Several gene mutations are associated with dystonia.
1-Idiopathic torsion dystonia (ITD) or Oppenheim’s dystonia
is predominantly a childhood-onset form of dystonia with an autosomal dominant pattern of inheritance that primarily affects Ashkenazi Jewish families.


The majority of patients have an age of onset younger than 26 years (mean 14 years). In young-onset patients, dystonia typically begins in the foot or the arm and in 60–70% progresses to involve other limbs as well as the head and neck. In severe cases, patients can suffer disabling postural deformities that compromise mobility. Severity can vary within a family, with some affected relatives having severe disability and others a mild dystonia that may not even be appreciated. Most childhood-onset cases are linked to a mutation in the DYT1 .

2-Dopa responsive dystonia (DRD) or the Segawa variant (DYT5)

is a dominantly inherited form of childhood onset dystonia , DRD typically presents in early childhood (1–12 years), and is characterized by foot dystonia that interferes with walking. Patients often experience diurnal fluctuations, with worsening of gait as the day progresses and improvement with sleep.
DRD is typified by an excellent and sustained response to small doses of levodopa .

B- Focal Dystonia

These are the most common forms of dystonia. They typically present in the fourth to sixth decades and affect women more than men. The major types are:
1- Blepharospasm dystonia: contractions of the eyelids with increased blinking that can interfere with reading, watching TV, and driving. This can sometimes be so severe as to cause functional blindness.

2- Oromandibular dytonia: contractions of muscles of the lower face, lips, tongue, and jaw (opening or closing).
Meige syndrome is a combination of OMD and blepharospasm that predominantly affects women older than age 60 years.
3- Saspmodic dystonia: dystonic contractions of the vocal cords during phonation, causing impaired speech. Most cases affect the adductor muscles and cause speech to have a choking or strained quality.

4- Cervical dystonia: contractions of neck muscles causing the head to deviate to one side (torticollis), in a forward direction (anterocollis), or in a backward direction (retrocollis). Muscle contractions can be painful, and associated with a secondary cervical radiculopathy.

5- Limb dystonia: These can be present in either arms or legs and are often brought out by task-specific activities such as handwriting (writer’s cramp), playing a musical instrument (musician’s cramp), or putting (the yips). Focal dystonia can extend to involve other body regions (about 30% of cases), and are frequently misdiagnosed as psychiatric or orthopedic in origin.

2- Secondary dystonia :

There are multiple reasons that may cause dystonia which either focal or generalized include :
1-wilson disease
2-Brain anoxia like in cerebral palsy
3-Trauma
4-manganese toxicity
5-infarction affecting basal ganglia
6-parkinson disease
7-Carbon monoxide poisoning
8-Drugs like anti psychotics, anti vertigo , anti emetics


Treatment of dystonia:
-Any case should be ruled out for Wilson disease
-In secondary type treat underlying cause, like stop the offending drug and give diphenhydramin i.v.
-In primary generalized type in childhood start trial of L- dopa for DYT5 or DYT1.
-Drugs can be given for focal or generalized dystonia like: triphenhexdyl ,baclofen ,tetrabenezine ,diazepam ,botulism toxin is the mainstay for all types of focal dystonia.
-Surgical treatment for refractory cases by deep brain stimulation

Chorea

It is rapid, semipurposeful, graceful, dancelike nonpatterned involuntary movements involving distal or proximal muscle groups.

Causes of chorea :

1-Hyperthyroidism
2-Oral contraceptive pills
3-SLE
4- Anti phospholipid syndrome
5- Sydenham chorea
6- Hungtington chorea
7- Chorea neuroacanthocytosis
8- Drugs like L –dopa , antipsychotics
9- Ataxia telengictasia
10-Hyper and hypoparathyroidism
11- Wilson disease
12- Paraneoplstic causes
13- non ketotic hyperosmolar hyperglycemia


Hungtington Disease
HD is a progressive, fatal, highly penetrant autosomal dominant disorder characterized by motor, behavioral, and cognitive dysfunction. Onset is typically between the ages of 25 and 45 years (range, 3–70 years) with a prevalence of 2–8 cases per 100,000 , HD is characterized by rapid, nonpatterned, semipurposeful, involuntary choreiform movements. In the early stages, the chorea tends to be focal or segmental, but progresses over time to involve multiple body regions.

Dysarthria, gait disturbance, and oculomotor abnormalities are common features. With advancing disease, there may be a reduction in chorea and emergence of dystonia, rigidity, bradykinesia, myoclonus, and spasticity. HD can present as an akinetic-rigid or parkinsonian syndrome (Westphal variant). HD patients eventually develop behavioral and cognitive disturbances, and the majority progress to dementia. Depression with suicidal tendencies, aggressive behavior, and psychosis can be prominent features. HD patients may also develop noninsulin-dependent diabetes mellitus and neuroendocrine abnormalities.

Treatment of HD :

Tetrabenazine , haloperidol, treatment of psychosis by atypical antipsychotic like resperidon or quetiapine.

The other cause of chorea treated by treating the underlying cause and by the same above drugs.

Sydenham Chorea

It is one of the major manifestations of rheumatic fever. It occurs in children, mainly girls, between 5 and 15 years of age and is now rare in the developed world. Widespread chorea, behavioral disturbance and obsessive-compulsive symptoms are common. It is self-limiting and usually resolves within 6 months, with about 20% of cases being recurrent.

D: Myoclonus

Myoclonus comprises sudden brief shock-like involuntary movements caused by muscular contractions or inhibitions. Muscle contraction produces positive myoclonus and muscle inhibition causes negative myoclonus or asterixis (e.g. liver flap). Myoclonus can be focal, multifocal, generalized, spontaneous or reflex. It may occur at rest, when maintaining a posture or during action.

Myoclonus can be classified as cortical, subcortical, spinal or peripheral, based on the presumed physiological mechanism underlying its generation. Alternatively, based on its aetiology, it can be classified as physiological, essential, epileptic or symptomatic .

Physiological myoclonus

This includes hypnic jerks (initial phases of sleep), hiccup (physiological myoclonus of diaphragm) and startle response .


Epileptic myoclonus
This term is used to denote conditions where myoclonic jerks are part of an epileptic syndrome, like jeuvnile myoclonic epilepsy, progressive myoclonic epilepsy.

Secondary myoclonus

This occurs in the context of an underlying neurological or nonneurological like renal failure , hepatic failure , brain anoxia , thyroid disorders ,drugs like amantidin , l-dopa , paraneoplastic , trauma to the brain and spinal cord , cns infection ,acute dissimenated encephalomyelitis ,prion disease , Wilson disease , non ketotic hyperosmolar hyperglycemia ,electrolyte disturbances.

Treatment

Treatment primarily consists of treating the underlying condition or removing an offending agent. Pharmacologic therapy involves one or a combination of GABAnergic agents such as valproic acid (800–3000 mg/d), piracetam (8–20 g/d), clonazepam (2–15 mg/d), or primidone (500–1000 mg/d). Recent studies suggest that levetiracetam may be particularly effective.

F:Tic

Tics are typically relatively brief rapid intermittent purposeless involuntary movements (motor tics) or sounds (vocalizations).
Classically, they can be suppressed, at least temporarily, by an effort of will, but at the expense of rising inner tension, often followed by a rebound exacerbation.

Transient tic means duration lessthan 1 year , the tic either simple or complex ,motor , sensory or vocal . Most tics are primay in orgin but there are secondary causes of tics

Secondary causes of tic :

1-fragile x syndrome
2-klinefilter syndrome
3-tuberous seclerosis
4-neurofibromatosis
5-post traumatic
6-infections like varicella and herpes zoster
7-hungtington disease
8- panda(Pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection)


Treatment of tic :
-aripiprazol , olanzapine ,clonidine ,resperidone , guanaficine.

Gilles do la tourette syndrome

is a neurobehavioral disorder named after the French neurologist Georges Gilles de la Tourette. It predominantly affects males, it composed at least of one vocal tic combined with multiple motor tics for at least one year before age of 12 years.

Motor tics can be simple, with movement only affecting an individual muscle group (e.g., blinking, twitching of the nose, jerking of the neck), or complex, with coordinated involvement of multiple muscle groups (e.g., jumping, sniffing, head banging, and echopraxia [mimicking movements]).

Vocal tics can also be simple (e.g., grunting) or complex (e.g., echolalia [repeating other people’s words], palilalia [repeating one’s own words], and coprolalia (expression of obscene words). Associated behavioral disturbances include anxiety, depression, attention deficit hyperactivity disorder, and obsessive-compulsive disorder. Patients may experience personality disorders, self-destructive behaviors, difficulties in school, and impaired interpersonal relationships , the symptoms disappear in adulthood
Thiscondition treated mainly by clonidine ,haloperidol , pimozide with cognitive behavior theraoy.

G: Hemiballismus

is a violent form of chorea composed of wild, flinging, large-amplitude movements on one side of the body. Proximal limb muscles tend to be predominantly affected.
The movements may be so severe as to cause exhaustion, dehydration, local injury, and in extreme cases, death. The most common cause is a partial lesion (infarct or hemorrhage) in the subthalamic nucleus (STN), but rare cases can also be seen with lesions in the putamen.

Fortunately, hemiballismus is usually selflimiting and tends to resolve spontaneously after weeks or months. Dopamine-blocking drugs can be helpful like haloperidol but can themselves lead to movement disorders. In extreme cases, pallidotomy can be very effective. Interestingly, surgically induced lesions or DBS of the STN in PD are usually not associated with hemiballismus.