Movement disorders Flashcards
Temor
rhythmic, oscillating movement of body part (hand)
ataxia
clusiness, instability, imbalance, or lack of coordination with voluntary movements
movements appear disjointed, unsteady gait, falls
(looks like they have been drinking too much)
Dystonia
- involuntary muscle spasms
- can be generalized or focal
tardive dyskinesia
- repetitive, purposeless, involuntary movements
- grimacing, lip-smacking, rapid arm/leg movements
- prolonged exposure to antipsychotics, neuroleptics
dysdiadochokinesia
impaired ability of rapid alternating movements
chorea
non-repetitive jerking movements of limbs, face or trunk
Essential tremor general
- involuntary, rhythmic, oscillatory movements (alternating contraction of opposing muscles)
- TWO TYPES
- Kinetic - tremmor with movement of body part (writing)
- Postural - tremor when body part held against gravity
- no related to neurologic disease or medications
- ONSET = 50’s
essential tremor Diagnosis****
- Based on history and physical
- usually asymmetic, hands > lower extremities
- tremor of head may sole symptoms or associated with extremity tremor
-
Need to rule out other disorders that may mimic essential tremor
- check thyroid function, ceruloplasmin
what would be some differential diagosis for essential tremor
- Hyperthyroidism –> bilateral tremor
- Parkinson’s disease –> tremor at rest
- enhanced physiologic tremor
- wilson’s disease
- medications = amiodarone, beta agonists, lithium, theophylline
TX of essential tremors**
targeted at symtpom management
-
Propranolol
- beta blocker, non-selective
- improved clinical symptoms and reported severity
- Primidone
- GABA effect
- may be more beneficial in the setting of Kinetic or intention tremors
pathophys of parkinsons
- loss of dopaminergic neruons in substania nigra
- neurons die and degenerate
- imbalance in DA:Ach in striatum = improper signalling pathway for cortical motor commands
DIANGOSIS OF PARKINSONS******
- Cardinal Signs/symptoms
- RESTING TREMOR (4-6Hz)
- COGWHEEL RIGIDITY
- BRADYKINESIA
- POSTURAL INSTABILITY
- Early motor symptoms
- micrographia, decreased exterity
- intermittent unilateral resting tremor
- hypophonia (softening of voice)
- stooping posture
- masked face
- shorter steps with unstead gait
describe the two main classifications of parkinsons
- Primary
- idiopathic parkinsons disease
- secondary parkinsons disease
- Infectious
- atherosclerotic
- drug induced
- toxic agents
- Head trauma, tumors
What is MPTP
- MPTP is a precursor to MPP+, a neurotoxin that destorys dopaminergic receptors in substania nigra
- Can be cause of secondary parkinsons disease
Describe general tx strategies
- treatment is targeted to symptom management (tx most bothersome symptoms first)
- Initiate treatment when patients begins having functional disability
- LIMIT Levadopa therapy in younger patients or those with expected long-term tx
Levodopa and carbidopa
(combo = Sinemet)
- Levodopa –> crosses BBB to act as dopamine
- Carbidopa –> inhibits peripheral degradation of levodopa by inhibiting dopamine decarboxylation
- ADVANTAGES: MOST EFFICACIOUS PD med, symptoms may improve
- DISADVANTAGE: does not STOP progression, require higher and higher doses due to wearing off effect (motor fluctuations)
- develop dyskinesia, choreoathetotic movements, dystonia
- DOES NOT STOP: freezing, instability, autonomic dysfunction
- High protein diets can effect absorption
DOPAMINE AGONISTS
- Bromocriptine
- Advantages
- direct dopamine stimulation
- good monotherapy in early PD
- no interference with dietary proteins/AA
- longer duration
- less motor complications
- Disadvantages
- not long term monotherapy
- still some motor complications
- DOES NOT STOP PROGRESSION
- DOES NOT TX: freezing, instability, autonomic dysfunction
MAO-B Inhibitors (B means Brain)
Selegiline, rasaligine
- Monoamine oxidase inhibits –> inhibits dopamine metabolism in the brain
- may be initial tx of pts with minimal functional disability
- Rasaligine –> may have neuroprotective effect
Anticholinergics
(Trihexyphenidyl, Benztropine)
- when dopamine decreases, cholinergic effects predominate
- TX is inteded to DECREASE CHOLINERGIC activity and balance the decreased dopamine effect
- Predominantly used for tremor
- ASE: dry mouth, urinary retention, altered mental status
COMT inhibitors
(entacapone, tolcapone)
- Increases duration of levodopa by inhibiting metabolism of levodopa by COMT
- adjunctive therapy with levodopa/carbidopa to decrease WEARING OFF effect
- NOT MONOTHERAPY
- monitor LFTs with tolcapone due to possible hepatotoxicity
Amantadine
Antiviral agent
- possibly useful early on, or as adjunct to levodopa therapy
- some antiparkinson activity
Surgical options
- intended for disabling PD despite optimal medical management
- poor candidates include those with high operative risk or significant congnitive decline
- OPTIONS:
- Ablation –> thalamotomy, pallidotomy
- DEEP BRAIN STIMULATION –> placed with stereotactic approach wtih MRI or CT
- Restorative –> fetal human/porcine nigral transplant