Hypokinetic Movement Disorders (18, part 1) Flashcards
What deficits characterize hypokinetic disorders (hypokinesias)?
Slowed movements with increased tone
Movement disorders are the result of damage to which structure?
Basal ganglia–> includes caudate, putamen, globus pallidus, subthalamic nucleus, substantia nigra
What are three frequently encountered hypokinesias?
- Idiopathic Parkinson’s disease
- Progressive supranuclear palsy
- Multiple system atrophy
What is the typical age range of onset in Parkinson’s? What does age have to do with prevalence?
55-65; prevalence increases sharply with age, especially over 70
(*by 80 years old, prevalence may be as high as 1:200)
What is the age cut-off for early-onset Parkinson’s?
Symptoms appear before age 50–> genetic factors more likely operative in these cases
Life expectancy of Parkinson’s ?
Close to normal with treatment, but not quite
What are the four primary features of Parkinson’s ? Which is most frequently 1st and which is not seen till late?
- Rest Tremor (most commonly the first symptom)
- Rigidity
- Bradykinesia (akinesia)
- Postural instability - NEVER seen in the first year of appearance of motor dysfunction in true idiopathic Parkinson’s –> balance impairment/falling
How do the motor features usually present initially? (unilateral or symmetric)
Typically are unilateral at first, but eventually become bilateral; initial asymmetry of dysfunction remains (side that started first will always be worse than the one that started later)
What is rigidity?
Increased muscle tone that is remains even with passive movement - (will stay stiff even when you manipulate the limb passively on physical exam)
*cogwheel rigidity = ratchet-like jerkiness with passive movement due to rigidity with tremor
What is rest tremor?
Tremor that appears with limb at rest and usually disappears with movement of the limb
If an individual with Parkinson’s type symptoms presents with postural instability (poor balance, falling down) w/in the first year of onset of motor symptoms what does this mean?
They almost certainly don’t have typical Parkinson’s, but rather another hypokinetic disorder ( progressive supranuclear palsy or multiple system atrophy)
What are secondary motor features that are characteristic of idiopathic Parkinsonisan’s?
- Masked face - reduced facial expressions
- Hypokinetic dysarthria - soft, slurred speech (characteristic!)
- Micrographia - handwriting gets smaller the longer they write
- Diminished blink frequency
Other than depression and anxiety (which may precede motor symptoms but are non-specific), what is a cognitive impairment that is seen in Parkinson’s ?
Executive dysfunction - difficulty making decisions or carrying out plans
* not a memory impairment; also should not appear early in course of disease, if does, then likely not idiopathic type Parkinson’s, but one of the other “Parkinsonism-plus”disorders
What is a common feature of Parkinson’s due to gastrointestinal autonomic dysfunction?
Constipation (prob most widely recognized)
What urinary symptoms due to autonomic dysfunction may occur?
Usually increased frequency/ urgency; some may have under active bladder function though
What cardiovascular autonomic signs may be evident in Parkinson’s ?
Orthographic hypotension
What symptoms may be seen due to autonomic thermoregulatory dysfunction in Parkinson’s?
Episodic profuse sweating (not to a dangerous degree, but may be aggravating/embarrassing)
What are 3 other symptoms of Parkinson’s (not related to sleep)?
- Anosmia (loss of smell, 90%)
- Blurred vision (particularly for near objects)
- Shoulder pain(may be presenting symptom, often misdiagnosed as bursitis)
What is the most characteristic sleep-related disorder for Parkinson’s? What is another common sleep complaint?
- REM sleep behavior disorder - retain ability to move while sleeping and will act out dreams
- Frequent awakenings (very common)
* #1 may be less common than 2’ but is highly CHARACTERISTIC of Parkinson’s, don’t confuse the two terms
What is the classic pathological abnormality in Parkinson’s?
Degeneration of pigmented nigrostratial neurons in the pars compacta of the substantia nigra
*as much as 70% may be lost by the time motor symptoms develop
What is the characteristic microscopic pathological lesion in Parkinson’s? Where found?
Lewy bodies - cytoplasmic inclusion bodies seen in the surviving neurons in the substantia nigra and elsewhere (like in the enteric nervous system)
What protein is responsible for Lewy bodies?
Alpha-synuclein
What is the neurochemical hallmark of Parkinson’s?
Dopamine deficiency- particularly in the substantia nigra in the midbrain and the striatum in the cerebrum
What are 3 “red flag” symptoms that would suggest that a person doesn’t have idiopathic Parkinson’s, but instead one of the other “Parkinsonism-plus” syndromes?
- Symmetrical presentation w/ absence of tremor
- Early falls (postural instability w/in 1st year)
- Unresponsiveness to Levodopa
What is bradykinesia?
Difficulty in initiating and terminating movement, slowness in carrying out movement, and difficulty with repetitive and/or simultaneous movements
What is different about the rigidity and different facial expressions seen with Progressive supranuclear palsy compared to Parkinson’s?
Rigidity - usually effects the axial musculature, may also cause neck extension (rather than the flexion seen in PD)
Facial expression - appears “astonished” rather than lack of expression seen in PD
What two symptoms may be more severe in PSP compared to PD?
- Postural instability - may even be the presenting symptom
2. Dysarthria - often early and severe
What symptom is characteristic of PD, but is rarely seen in PSP?
Tremor
What behavioral symptom is frequently seen in PSP, but not seen in either PD or multiple system atrophy?
Dementia - memory affected, unlike in PD
What opthalmologic feature is a very definining feature and may even permit diagnosis of PSP?
Supranuclear gaze palsy - impairment of volitional downgaze (pt. cannot look down)
- leads to “dirty tie” sign (messy eating) or difficulty going down stairs
- in PD, the pts sometimes have trouble looking up, not down
What is apraxia of eye opening, another opthalmologic feature of PSP?
Difficulty opening closed eyes when asked to do so–> but can still do it spontaneously
What signs may be present in PSP that is not present in PD?
Pyramidal tract signs - like positive Babinski; indicates upper motor neuron damage
(Sleep disturbances may be present as well)
Grossly, what 2 regions of the brain show atrophy in progressive supranuclear palsy?
Midbrain and cerebral cortex
What protein is abnormally deposited in progressive supranuclear palsy? What structures are seen?
Tau protein–> seen in neurofibrillary tangles (unpIred straight filaments contained phospharylated tau protein)
What three structures in brain show neuronal loss and gliosis in PSP?
- Globus pallidus
- Pedunculopontine nucleus
- Substantia nigra
What is the most prominent neural helical abnormality of PSP?
Nigrostratial dopaminergic deficiency
What is the age range of onset for Multiple System Atrophy?
50-55 (also younger than PD); similar to PSP however
*life expectancy ~ 5-10 years (maybe shorter than PSP)
What three different clinical patterns may be observed in Multiple System Atrophy?
- Parkinsonism (eventually develops in ~90%)
- Progressive autonomic failure
- Cerebellar syndrome
* used to be considered 3 distinct diseases
What two neurological symptoms does multiple system atrophy share with PD? What features are similar to PSP?
Rigidity and Bradykinesia are typically seen
-like PSP, postural instability occurs early and also tremor is unusual
Although it doesn’t affect all patients, what general features are considered a clinical hallmark of Multiple system atrophy?
Progressive autonomic failure - orthostatic hytension is perhaps the most widely recognized
*appears earlier and is more sever than that seen in PD; seen in 78% of pts with MSA
What are 4 symptoms that may be due to cerebellar dysfunction in MSA?
Ataxia, dysarthria, coulombs or abnormalities, exaggerated rebound
*may only be evident in 55% of patients
What pyramidal feature may be seen in MSA that is not seen in the others? What is one shared by PSP?
- Hyperreflexia
2. Positive Babinski
What behavioral condition EXCLUDES a diagnosis of MSA? Which may be more characteristic for MSA than the others?
Dementia- not seen in MSA and may exclude the dx (seen only in PSP)
Personality changes - more characteristic of MSA
-also shares executive dysfunction as a feature, along with PD
What are two “other” features that are characteristic of MSA? Which one may increase the risk of sudden death?
- Involuntary sighing
- Respiratory stridor
* Raynaud’s and postural myoclonus are additional characteristic features
What two areas of brain outside of brainstem, cerebellum, and spinal cord are characterized by cell loss and gliosis in Multiple System Atrophy?
Substantia nigra and posterior putamen
What is the typical age of onset for Progressive supranuclear palsy?Life expectancy?
50-60 ( so somewhat younger than Parkinson’s; is also more rare)
Life expectancy is only about 10 years after dx- there is currently no effective treatment
What is the microscopic pathological hallmark of MSA? What protein causes?
Glial cell cytoplasmic inclusion bodies –> stain for alpha-synuclein
* is in glial cells rather than neurons themselves as it is in PD, so don’t fuck that up
