Parkinsons Disease

Question 1

Definition

Answer 1

Chronic, progressive, neurodegenerative disorder resulting from the degeneration of dopamine producing neurones in the substantia nigra of the basal ganglia

Question 2

Risk factors

Answer 2

Environmental factors
Genetic factors
Pesticides
Genetic mutations

Question 3

4 Cardinal signs

Answer 3

Bradykinesia - slow movement
Rigidity
Resting tremor
Postural instability

Question 4

Function of the basal ganglia

Answer 4

Well-learned motor skills and movement sequences
Preparation and planning
Initiation and termination
Sequencing and timing
Regulating muscle tone and inhibition of antagonistic muscles

Question 5

What are the 5 nuclei of the basal ganglia

Answer 5

Globus pallidus
- internus and external
Caudate
Putamen
Subthalamic nuclei
Substantia nigra
- pars compacta
- pars reticulata

Question 6

Secondary clinical symptoms

Answer 6

Difficulty initiating and terminating movement
Fatigue
Freezing
Sleep disorders
Dysphagia
Anxiety and depression
Festinating gait pattern - shuffling

Question 7

What are the 2 basal ganglia pathways

Answer 7

Direct - promotes movement - go pathway
Indirect - inhibits movement - stop pathway

Question 8

Explain the direct pathway

Answer 8

Cortex sends excitatory signals to the striatum
Striatum sends inhibitory signals to the globus pallidus internus and substantia nigra pars reticulum
Meaning no signals are sent to the thalamus
Meaning the thalamus is not sending signals resulting in more excitation to context so more movement

Question 9

Describe the indirect pathway

Answer 9

Cortex sends excitatory to striatum
Striatum sends inhibitory to globus pallidus externus
- meaning inhibition isnt sent to the sub thalamic
Cortex sends excitation to subthalamic as not getting inhibition from GPE
Excitation sent to globus pallidus internus and substantia nigra pars reticulum
They send inhibitory to thalamus
Meaning less excitation to cortex and less movement

Question 10

What is dopamines role

Answer 10

Dopamine excites direct (go)
Dopamine inhibits indirect (stop)
- dopamine promotes movement

Question 11

Parkinson’s effect on dopamine

Answer 11

Parkinson’s is a lack of dopamine
Less excitation of direct
Less inhibition of indirect
- less movement

Question 12

Medications

Answer 12

Dopamine replacements
- replace lost dopamine but dopamine cannot cross the blood/brain barrier
- these medications contain drugs that facilitate the crossing to the brain
- e.g madopar, sinemet
Dopamine copycats
- aka dopamine agonists
- e.g apomorphine, perdolide
Dopamine protectors
- protect current levels of dopamine by blocking enzymes that break it down
- e.g MAO-B inhibitors

Question 13

Secondary effects of medication

Answer 13

Various and wide ranging
Especially when considering variety of meds people end up taking
Treatment:
- deep brain stimulation

Question 14

Postural instability

Answer 14

Develops later in the disease
Characterised flexed posture
flexed hips and knees
Unable to access balance reactions

Question 15

Appearance of PD

Answer 15

Stooped posture
Masked facial expression
Rigidity
Forward tilt of trunk
Flexed elbows and wrists
Reduced arm swing
Slightly flexed hips and knees Unable to
Trembling of extremities
Shuffling, short-stepped gait

Question 16

Principles for enhancing function

Answer 16

Cueing
Duel tasking
Balance training
Gait re-education
Symptom specific exercise