Parkinson I Flashcards
Parkinson definition
progressive disorder of the CNS with both motor and nonmotor symptoms
PD incidence
affects 1 million Americans
7 to 9 million worldwide
~2% over 65 have PD
Alzheimers only other neuro degenerative disorder more common
average age of onset is 50-60 yo
Parkinsonism
generic term used to describe disorders of the basal ganglia (BG)
PD clinical subgroups
- Postural instability gait disturbed(PIGD)-poor balance and changes in gait
- Tremor predominant-tremor usually primary characteristic. Few problems with bradykinesia or postural instability.
Secondary Parkinsonism-
4 types
- Postencephaic parkinsonism
- Toxic parkinsonism
- Drug-induced parkinsonism
- Metabolic conditions
Postencephalic parkinsonism
result of influenza outbreak in 1917-1926
this type no longer seen. most individuals have passed.
Toxic parkinsonism
symptoms occur in individuals exposed to certain environmental toxins, including pesticides and industrial chemicals
occurs secondary to long term exposure to toxins
maganese is the primary culprit
Drug-induced parkinsonism
variety of drugs can produce exrapyramidial dysfunction that mimics the signs of PD
interfere with dopaminergic mechanisms either presynap or postsynap
once medication is removed symptoms generally reverse
medications responsible- neuroleptic drugs, antidepressant drugs, antihypertensive drugs
Metabolic conditions
result in calcification of the basal ganglia
hypothyroidism, hyperparathyroidism, hypoparathyroidism, and Wilson’s disease (too much copper in brain and liver)
Parkinson’s plus syndrome
group of neurodegenerative diseases that produce symptoms of PD and affect the substantia nigra
Diseases: Shy-drager syndrome (slowness of movement, rigidity, poor balance. Now called multiple system atrophy)
Progressive supranuclear palsy (rare brain disorder that affects control of gait and balance)
Multi infarct vascular disease
Alzheimers
CTE
Creutzfeldt Jakob (fatal brain disorder-mad cow disease)
PD Pathophysiology
degeneration of dopamine producing neurons in the substantia nigra of the basal ganglia
disruption occurs in the dopamine-acetylcholine balance in the basal ganglia
symptoms don’t occur until 30-60% of the substantia nigra cells have been lost
Cortex talks to the basal ganglia and the BG and thalamus coordinate the motion
PD defined by (1) degeneration of dopaminergic neurons in the BG in the pars compactus of the substantia nigra that produces dopamine and (2) as the disease progresses and neurons degenerate, the presence of Lewy bodies.
Primary motor symptoms
- Rigidity
- Bradykinesia
- Tremor
- Postural instability
Rigidity
increased resistance to passive motion
one of clinical hallmarks of PD
2 types
Often asymmetrical, especially the early stages of PD
Affects the proximal muscles first
Results in decreased ROM and increasing energy expenditure and fatigue levels
Cog-wheel rigidity
jerking, ratcher like resistance to passive motion as the muscles alternate between contraction and relaxation
Lead pipe rigidity
a sustained resistance to passive movement, no change in resistance
Bradykinesia
slowness of movement
insufficient muscle recruitment during initiation
internally signals are scaled down prior to being sent to activate muscles
akinesia- poverty of spontaneous movement
Freezing-occurs with a change of stimuli. Generaly short lived.
hypokinesia-slowed or reduced movements can also be seen in PD
Tremor
involuntary shaking or oscillatory motions of a portion or segment of the body
caused by alternating contractions and relaxation of agonist and antagonist muscles
postural tremor- tremor of head or neck
resting tremor-present a rest but disappears with action (most common type in PD)
action tremor- occurs at rest and continues with movement. appears later stages of PD.
Postural instability
result of abnormalities of posture and balance
poor postural responses
inflexible responses
difficult controlling COM
attentional demands greatly impact postural stability
rare in the early years (ex 5 after diagnosis)
leads to greater fall risk
Secondary motor symptoms
- muscle function
- muscle performance
- GAIT
SMS-Muscle function
strength reduced-could be dopamine related (better with “on” period)
torque reduced at all speeds
motor units-recruitment reduced and delayed (“under recruitment”)
fatigue- one of most common symptoms reported. Difficulty sustaining any activity. Individual muscles fatigue quickly as well. -dopa therapy can help with fatigue.
SMS-Gait
Up to 1/3 of PD patients present with gait disturbance as their initial motor symptom
reduction in arm swing and asymmetry
Festinating Gait-progressive increase in speed and shortening of stride length. Cause by an abnormal stooped posture.
Other gait characteristics- narrow BOS, forward posture, flexed knees
SMS-motor function
motor planning deficits evident in PD
loss of regulatory control in autonomic and involuntary movement
movement preparation is prolonged
start-hesitation especially evident as disease progresses
Non-motor symptoms
- Sensory symptoms
- Dysphagia
- Speech disorders
- Sleep disorders
- Cognitive dysfunction
NMS-Sensory symptoms
primary sensory loss does not occur
up to 50% of patients report parethesias (burning, tingling, numbness, pain, or pricking sensation). Could be from the disease’s effect on central nociception.
Postural stress syndrome- results from poor postures and strain on ligaments, muscles, and joints. Causes pain. Ex. back pain may accompany a prolonged, stooped, kyphotic posture.
Proprioceptive regulation of voluntary movement may also be impaired. Difficulty in perceiving the extent of movement.
Olfactory dysfunction is common- decline or loss in sense of smell (anosmia).
NMS- Dysphagia
impaired swallowing due to rigidity, reduced mobility, and restricted ROM
presents in 95% of PD patients
considered an early symptom of disease
complications- nutritional deficiency and aspiration pneumonia
probems with tounge control, delayed swallow response, and chewing. Can cause choking and weight loss.
Sialorrhea (drooling)- increased saliva production and inability to manage secretions due to dysphagia
NMS-Speech disorders
hypokinetic dysarthria- decreased voice volume, monotone, imprecise speech ad altered articulation/pronouncement
Huge social impact- one of the reasons patients stay at home
NMS- Cognitive dysfunction
mild (mild impaired memory) to severe (dementia)
Bradyphrenia- slowed thinking.processing. One of the first signs of PD, however often missed.
Dementia with PD is very common
The lower cognitive function the higher mortality risk
Behavioral changes
NMS-Sleep disorders
insomnia common- falling asleep and staying asleep[
daytime somnolence common (sleepiness)
active sleeping- enacting dreams and intense vivid dreaming.
