Movement disorders Flashcards
what is the role of the basal ganglia
initiation and modulation of movements
receives input from cerebral cortex and relays it back to the cerebral cortex via the thalamus via direct (enhance outflow of thalamus) or indirect (inhibits thalamus outflow) pathways
what are the two types of movement disorders
hypokinetic (too little movement)
hyperkinetic (too much movement)
what descending pathway do basal ganglia disorders affect
extra pyramidal
what features are seem in pyramidal (corticospinal)/ UMN lesions
pyramidal weakness= arms: extensor weaker than flexor
legs: flexors weaker than extensors
spascticity
what are the features of a extrapyramidal/ basal ganglia lesion
hyperkinetic:
- dystonia
- tics
- myoclonus
- chorea
- tremor
hypokinetic:
-parkinsonism
what are the motor features of a cerebellar lesion
ataxia- lack of voluntary coordination of muscle movements that can include gait abnormality, speech changes and abnormalities in eye movements
what is the most common neurodegenerative disease
alzeheimers, followed by parkinsons
what is the pathology of parkinsons
loss of black pigment correlating to the degeneration of dopaminergic neurones in basal ganglia (substantia nigra (pars compacta region) and locus coeruleus)
presence of lewy bodies
what causes parkinsons
idiopathic
advancing age
genetic and environmental factors
5% familial
what are the clinical features of parkinsons
tremor (resting, slow reemergence of tremor when in posture, often asymmetrical)
bradykinesia
rigidity
postural instability
non motor: sleep disorders (RBD) hallucinations GI dysfunction (constipation) depression cognitive impairment dementia anosmia
what are the three subtypes of parkinsons motor features
- tremor dominant (with relative absence of other motor symptoms)
- non tremor dominant (such as akinetic, rigid syndrome, postural instability)
- mixed
which motor subtype of parkinsons has the best prognosis
tremor dominant has slowest progression and less rate of physical disability
what are the common pre motor/ prodromal symptoms of PD
constipation, RBD, excessive daytime sleepiness, hyposmia, depression
how do you test bradykinesia
finger tapping
will have decrements in amplitude/ speed of movement and fatiguing
what are the features of advanced PD
urinary symptoms orthostatic hypotension dementia dysphagia postural instability freezing of gait falls fluctuations dyskinesia psychosis
what are the essential features for a PD diagnosis
bradykinesia and one more of the following: resting tremor, rigidity (cog wheel or lead pipe), postural instability).
Additional motor features: stooped, fixed posture, dystonic postures, hypomimia (masked face), shuffling, short stepped gait (+/- festination= running after their centre of gravity).
Additional non motor: late onset hyposmia, depression, anxiety, constipation, bladder problems, pain, subtle mental or cognitive impairment
what should patient with suspected PD not present with
early onset bulbar problems (CN 9-12)
dementia
hallucinations
preferential involvement of lower limbs
prominent eye movement disorder (e.g. supranuclear palsy= problems in voluntary upwards and downwards movement)
intrusive early autonomic problems (e.g. bladder control)
what imaging can be done for a PD diagnosis
brain imaging
DaTSCAN (nuclear medicine presynaptic dopaminergic imagine- if comma shaped = possible essential tremor. If period shape= possible parkinsons tremor)
who gets parkinsons
all ethnicities
men more likely
old age
what are the risk factor for parkinsons
old age family Hx male environmental: -pesticides -head injury -rural living -beta blocker use -farmer -well water drinker
what decreases you risk of parkinsons
tobacco smoking coffee drinking NSAID use CCB use alcohol consumption
what are the monogenic forms of parkinsons
LRRK2
PARKIN
what do symptomatic treatments do in PD
enhance intracerebral dopamine concentrations/ stimulate dopamine receptors
what are the symptomic PD drugs
levodopa (best, given >65/70s) dopamine agonists (if patient young) monoamine oxydase type B inhibitors (adjuvant/ early disease) amantadine (NMDA antagonist)
when should you start Tx in parkinsons
when symptoms cause disability/ discomfort
what in PD responds well to dopaminergic treatment
bradykinesia and rigidity in early phase of disease
tremor is inconsistently responsive
what drugs can be effective for tremor
anticholinergics
trihexphenidyl
clozapine
what type of drug is levodopa and cardibopa
levo- dopamine precurosor
carbi- carboxylase inhibitor
what are the side effects of PD medications
dopamine agonists and levodopa- nausea, daytime somnolence, oedema
dopamine agonists- impulse control disorders (gambling, hypersexuality, binge eating, spending) - avoid in Hx of addiction/ impulsive personality. hallucinations (avoid in elderly with CI)
levodopa best symptomatic benefit but longterm use is associated with motor complications (dyskinesia and motor fluctuations)
what are the long term complications of dopamingeric therapies for PD
motor fluctuations- (periods of good and bad motor symptom control)
non motor fluctuations
dyskinesia (involuntary choreiform or dystonic movements)- happens when levodopa is at highest conc
drug induced psychosis- hallucinations
what eye movement problems can you get in parkinsons
vertical gaze palsy and slow saccade = progressive supranuclear palsy
what eye movement problems in huntingtons
difficulties initiating saccades