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
