CM- Movement Disorders Flashcards
What is a tremor?
What are the 4 types?
A tremor is a rhythmic oscillation of any body part.
Amplitude = variable
Frequency = predictable
- essential tremor - arms, hands, fingers during eating and writing
- rest tremor- occurs when the muscles are relaxed [lying at sides, on lap]
- dystonic “tremor” -twisting and repetitive motions and/or painful and abnormal postures or positions, such as twisting of the neck (torticollis) or writer’s cramp
- task-specific tremor -occurs with a highly specific task like writing or speaking
A patient presents with a paucity of spontaneous movement and decreased amplitude of movement. What is this called?
What is it called if the person has absent spontaneous movement?
Bradykinesia = slowness, paucity of spontaneous movement
Akinesia = absence of spontaneous movement
A patient presents with laterocollis, torticollis, anterocollis, or retrocollis. These are examples of what?
What is the reason why these occur?
These are examples of focal dystonia and are due to abnormal muscle contractions leading to sustained posture [co-contraction of agonist-antagonist]
Patterned/predictable muscle postures
interrupts and induced by limb movement
What is blepharospasm?
dystonia where there is contraction of the b/l obicular ocularis [uncontrolled contraction of the eyelids]
A patient presents with non-rhythmic, abrubt, unsustained writhing. The movements occur at random, unpredictable times and appear as dance-like, flowing movements. What is this an example of?
Chorea
A patient has proximal, large-amplitude hemibody movements. What is this called?
What is the pathophysiology behind the problem?
Hemiballism- caused by a lesion in the contralateral STN of the basal ganglia disrupting inhibition of the “indirect circuit” and increasing thalamic firing
A patient presents with a non-rhythmic, abrupt, unsustained “jerk-like” movement.
It is random, and unpredictable in timing. What does this describe?
What disorder are you likely to see it with?
What is the pathophysiological cause?
Myoclonus which is often seen with HD.
Pathophysiology: dysregulation of the pyramidal pathways from the cortex to the spinal cord
What can induce myoclonus?
- spontaneous
- reflexive
- action-induced
- wake-sleep transition
What is a tic?
What are examples of motor tics?
What are examples of phonic/verbal tics?
Tic is a brief, repetitive, stereotypic movement or sound.
URGE–> tic–>transient relief–> URGE
Motor: dsytonic, myoclonic, stereotypic, complex
Verbal: guttural sounds, throat-clearing, coprolalia[swearing]
A patient was started on anti-psychotics a few weeks ago.
Now they are presenting with abnormal movements with complex, repetitive chewing movements, tongue protrusion, and choreiform limb movements, pelvic thrusting and dystonia.
What is the likely problem?
Tardive dyskinesia/dystonia
-often iatrogenic
What is dyskinesia?
Abnormal, involuntary, hyperkinetic movements
What are the 6 components of parkinsonism?
- bradykinesia
- stooped posture
- shuffling gait [“freezing gait’]
- resting tremors
- postural instability, falls
- cogwheel rigidity [resistance to movement around a joint]
What falls under the broad category of parkinsonism?
- parkinson’s disease
- stroke
- iatrogenic/medications
- neurodegenerative disorders [Multiple System Atrophy affecting autonomics, nervous system, movement
What are 5 neurodegenerative diseases that can closely mimic PD?
- MSA -multiple system atrophy
- DLBD- diffuse lewy body disease
- CBD- cortico-basal degeneration
- PSP- progressive supranuclear palsy
- Alzheimer’s
What is the pathophysiology behind Parkinson’s disease?
- Loss of dopaminergic neurons in the substantia nigra, zona compacta–> progressive degeneration of basal ganglia connections, accumulation of Lewy bodies/a-synuclein
- widespread neurotransmitter dysregulation
- Locus ceruleus [NE]
- dorsal raphe [serotonin]
- nucleus basalis of Meynert [Ach]
- GABA, glutamate
At what age does PD usually present?
Are most cases sporadic or genetic?
It is adult onset [age 21 and up, with the avg age being 60]
Most cases are sporadic and idiopathic.
Fewer cases are genetic:
AR - Park 2, 6, 7, 3 10 14 15 16
AD- Park 1, 8, 5, 11, 13, 17,18
What motor symptoms are associated with Parkinson disease?
- asymmetric rest tremor
- cogwheel rigidity
- bradykinesia
- postural instability
- flexed posture [stooped]
- freezing [shuffling gait]
What is the core diagnostic criteria for PD?
[if no labs or imaging is available]
- Bradykinesia and at least one of the following
- rigidity
- rest tremor
- postural instability
What criteria is supportive for PD?
3 of the following:
- response to levodopa
- responds to med for >5 years
- clinical course of >10 years
- unilateral onset
5, persistent asymmetry - rest tremor
- progressive
When attempting to diagnose PD, what criteria would be:
- definitive
- probable
- possible
Definitive:
- clinical
- histological
Probable:
- 3/4 [rigidity, asymmetric, bradykinesia, postural instability]
- exclude other etiology
- responds to L-dopa
Possible:
- tremor OR bradykinesia + rigidity OR asymmetry
- exlude other etiology
- response to L-dopa
Describe why parkinson’s disease is hypokinetic.
Lack of dopamine –> more inhibition of lateral globus pallidus–> less inhibition of STN –> more activation of SNr and MGP–> more inhibition of the thalamus –> less activation of the cortex
Describe hyperkinetic disorders via pathway in the basal ganglion,
More inhibition of STN–> less activation of SNr, GPi–> less inhibition of thalamus–> more activation of the cortex
What are the 4 main types of drugs used to treat Parkinson’s?
- Levodopa, carbidopa
- COMT inhibitors [entacapone, tolcapone]
- MAO-B inhibitors [selegeline, rasagiline]
- Dop agonists [ropinirole, pramipexole]
What are signs that a neurodegenerative case might not be PD, but rather MSA, DLBD, PSP, CBD?
- no response/inadequate response to levodopa
2 cognitive decline on neuropsych testing - significant comorbidities
- psych disorder inadequately treated
What does the pneumonic DBS in PD mean?
Deep Brain Stimulation:
- Does not cure PD
- Bilateral to improve gait
- Smooths out “on-off” fluctuation
- Improves tremor, rigidity, dyskinesia, akinesia,[postural instability responds least]
- Never improves L-dopa unresponsive symptoms
- programming required freq followup
- decreases meds, does NOT eliminate them
What is the most prevalent movement disorder?
Who is most frequently affected by it?
How is it inherited?
Essential Tremor- action tremor that affects bilateral limbs +/- head and voice tremor with the absence of other progressive neuro signs
It has a bimodal distribution with peaks in the second and sixth decade [1-10% of the population over 65]
It is autosomal dominant
What is the pathophysiology of essential tremor?
- Cerebellum is thought to be a generator
- “torpedos” - swelling of proximal purkinje cells in the cerebellum
Loss of purkinje cell inhibition to thalamo-cortical motor neuron pathways –>spontaneous depolarization or oscillation resulting in tremor
What drugs are used to treat essential tremors?
What are the surgical treatments for essential tremor?
Meds:
Beta blockers - propanolol, primidone
Surgery:
- Lesioning Vm thalamic nuclei can disrupt cerebello-thalamic-cortical motor neuron loop
- thalamic DBS
- Thalamatomy [surgical ablation of Vm]
Writers and musician’s cramp are example of what movement disorder?
Focal “task-specific” dystonia
What is the mechanism behind tardive dystonia?
How is it treated?
- dopamine D2 receptor blockade [from antipsych drugs]
- supersensitivity and upregulation of SN postsynaptic receptors
Treat by:
- Eliminate the dopamine receptor blocking agent
- add atypical antipsychotic w/ low affinitD2 receptors, bind 5HT receptors and have low propensity for tardive dystonia
- dopamine depleters
- anticholinergics for dystonia
What is treatment for dystonia?
- L-dopa
- anti-cholinergics
- antihistamine
- benzodiazapine
- GABAb agonists
A patient presents with elevated LFTs. He has a “wing-beating” tremor, dysarthria and drooling, dystonia and Parkinsonism. He is cognitively impaired and has dementia and psychosis.
On physical exam, you note Kayser-Fleischer rings in his eyes seen with the slit lamp exam.
What is the likely diagnosis?
How do you make the diagnosis?
What is treatment?
Based on presentation, this seems to be Wilson’s Disease [inborn error in copper metabolism that causes hepatic cirrhosis and basal ganglia damage].
Diagnosis:
- High serum Cu, low ceruloplasmin, high urine Cu
- Liver biopsy
- Genetic test
Treatment: D-pencillamine, liver transplant
What are the primary causes of hemiballism/hemichorea in the elderly?
The young?
Elderly = vascular, nonketotic hyperglycemia Young = infectious, inflammatory
A 9 year old girl had a recent GABHS streptococcal pharyngitis.
She is now presenting with chorea, motor impersistance, hypotonia and a tic. She also is demonstrating behavioral abnormalities.
What do you suspect that her labs will show?
What do you think the issue is?
What 4 types of drugs should you consider to treat?
Her presentation sound like Sydenham’s chorea [part of Jones criteria for rheumatic fever, a sequelae of GABHS infection]
Labs show:
- elevated antistreptolysin O
- elevated DNA-ase B
- throat culture for s. pyogenes
Treatment:
- antiepileptic
- dopamine antagonist/depleter
- treat the rheumatic heart disease
- penicillin
What drugs are used to treat symptomatic chorea?
- dopamine receptor blockade
- presynaptic dopamine depletion
- glutamate antagonist
- antiepileptic
- GABA agonist
Describe the genetics of Huntington disease.
It is an autosomal dominant disease that is due to a mutation on chromosome 4 [Huntingtin gene]. It is a CAG [polyQ] repeat. 27-35 = premutation 36=39 = 40 = 100% >60 = juvenile onset
What is the Huntington clinical triad?
- chorea and other motor features
- psychiatric -[depression, personality change, OCD]
- cognitive [exec function, dementia]
What age does Juvenile Onset Huntington disease usually begin?
What is the inheritence?
How many repeats are there likely to be on chromosome 4?
What is the clinical phenotype?
Before 21
autosomal dominant- paternal inheritence
>60 repeats [if over 80 they get it before 10]
Parkinsonism
Dystonia
Myoclonus
Seizures
What are the 6 main clinical requirements for a tic to be considered Tourette’s syndrome?
- multiple motor and phonic tics
- tics many times a day for atleast a year
- location, freq, number, severity vary
- before age 21
- no other explanation
- witnessed by examiner
A parkinson’s patient is over the age of 65 and is in late stage parkinson’s. They have no cognitivie/psychiatric symptoms or comorbidities. What medicine should they be on?
Levodopa
A Parkinson’s patient is under 65 with mild/moderate stage disease. They do not have any cognitive/psych symptoms or comorbidities. What drug should they be on?
Dopamine agonist [ropinirole, prampexole]
What 2 drugs should be avoided in patients with cognitive/psych symptoms and parkinsons?
- dopamine agonists
2. amantadine– glutamate antagonist
What Parkinson drug should be avoided with meds that potentiate 5HT, NE or monoamines in the brain?
MAO-B blockers because you can get HTN
What parkinson drugs should be avoided in CHF, renal failure and patients over 75?
Amantadine
