movement disorders
TRANSCRIPT
Introduction
Spectrum
Abnormalities in muscle tone, in coordination and apraxias are now classified under movement disorders
Clinical sign, not diagnosis.
Approach is different:
what class is the movement disorder.
Is it primary or secondary
Tremor
Rythmic oscillation of a body part, produced by either
alternating or synchronous contractions of reciprocally innervated antagonistic muscles
Fixed frequency
Amplitude can vary widely
Rest
Postural
Intention
Rest Tremor
occurs with body part in complete repose, and often dampens or subsides entirely with action.
Onset is most commonly in arms, often asymetrically
Can affect the face ( lips and jaw)
Usually starts distally.
Usually disappears during sleep
Distraction often brings out the tremor
Causes of Rest Tremor
Parkinsons disease and other parkinsoniansyndromes
Midbrain or rubral tremor (holmes tremor)
Wilsons disease
Essential tremor
Postural Tremor
Tremor that is present on maintenance of a posture
Many are mistaken as having “bad nerves”
Can be associated with terminal accentuation
Anxiety and stress worsen the tremor
Causes of Postural Tremor
Physiological tremor
Essential tremor
Anxiety, fatigue, emotion, stress, hypoglycemia, thyrotoxicosis, phaeochromocytoma, drugs etc
Primary writing tremor
Orthostatic tremor
PD (re-emergent tremor)
Cerebellar
Midbrain tremor
Psychogenic
And many others
Dystonia
Disorder dominated by sustained muscle contractions, which often cause twisting and repetitive
movements or abnormal postures.
Slow and twisting
Rapid (myoclonus like)
Superimposed rythmic movements
Stress and anxiety aggravate the movements
Sensory tricks
Can be task specific
Dystonia
Primary ( pure, no other signs)
Secondary ( dystonia-plus syndrome)
Examples:
Blepharospasm
Oromandibular or lingual dystonia
Laryngeal dystonia
Cervical dystonia
Axial dystonia
Chorea
Greek choreia= dance
Irregular, unpredictable, brief, jerky movements that flow randomly from one part of the body to another.
Choreoathetosis is slow chorea.
Aggravated by standing and walking
Motor impersistence (esp. in HD)
Chorea
Acute or subacute onset?1. Cerebral infarcts, Sydenham chorea, hyperthyroidism, SLE,
neuroleptic withdrawal, chorea gravidarum
Slow and insidious onset?1. Huntingtons disease, benign hereditary chorea(TITF1 gene)
Relapsing remitting pattern?1. SLE, Drugs
Family history!
Tardive dyskinesia
repetitive stereotypical movements which are most pronounced in the orolingual region.
Speed and amplitude can increase markedly with distraction.
Patients have voluntary control over movements and can suppress them
Tongue protrusion is manageable, with no motor impersistence
Gait is often normal
Tardive dyskinesia
Causes:
Dopamine receptor blockers (antipsychotics, metoclopramide)
Dopamine agonists, anticholinergics, antihistamines all cause a similar type of dyskinesia
Multiple infarctions in the basal ganglia
Cerebellar vermis lesions
NMDAR encephalitis associated with ovarian or testicular tumours
Idiopathic oromandibular dystonia
Ballism
Uncommon
Greek = “to throw”
High amplitude movements, violent, flinging in nature
Rapid and nonpatterned
Involve more proximal muscles
Usually involves one side of body, hemiballismus
Commonly associated with other movement disorders such as chorea and dystonia
Cause: lesion in contralateral subthalamic nucleus or striatum ( eg. Vascular, tumors, infections, NKHS, drugs)
Tics
Brief, intermittent movements (motor tics) or sounds (phonic tics)
Sudden, transitory, often repetitive and stereotypical that may mimic fragments of normal behaviour
Inner urge to make movement, or local premonitory sensation temporarily relieved by the tic
Can be suppressed voluntarily, however patients feel mounting tension inside to perform the tic
Increase with stress, increase at rest! Simple tics and complex tics Negative tics
Tics
Causes:
Primary; Tourette syndrome, Huntington disease, Neuroacanthocytosis
Secondary; infections, drugs, toxins, head trauma, stroke
Myoclonus
Sudden, brief, shocklike involuntary movement possibly caused by active muscle contraction (positive myoclonus) or inhibition of ongoing muscle activity (negative myoclonus)
Clinical patterns vary widely; frequency, amplitude, distribution
Usually arrhythmic and irregular, but can sometimes be rhythmic (eg. Oscillatory myoclonus)
Myoclonus Causes
Physiological myoclonus (normal subjects)
• Sleep jerks (hypnagogic jerks), anxiety or exercise induced, hiccup
Essential myoclonus (no known cause or neurological deficit)
Sporadic or hereditary
Epileptic myoclonus (seizures dominate and no encephalopathy)
Fragments of epilepsy, childhood myoclonic epilepsies, progressive myoclonic epilepsies
Symptomatic myoclonus (progressive or static encephalopathy
dominates) Storage diseases, spinocerebellar degeneration, basal ganglia degeneration, mitochondrial
encephalopathies, dementias, viral encephalopathies, metabolic, toxic, focal CSN damage
Others
Restless leg syndrome; 14% of women and 7% of men older than 50.
Psychogenic movement disorder; Common Clues are:
Somatic and psychiatric complaints Movement disorders not categorizable or typical of a certain class or showing a
combination of many classes Sudden onset(often in relation to physical or emotional trauma) Secondary gain Variable frequency of tremor Distractibility Exaggeration of symptoms