Week 6 Content 2

Parkinson's and Huntington's disease

Parkinson’s disease

Neurodegenerative disease, gradual onset and progressive worsening, typically older age at onset and prevalance increases with age

Young onset parkinson’s disease

Occurs in people younger than 50

Subtypes of parkinson’s

Postural instability gait difficulty PIGD and tremor dominant parkinsons

Causes of parkinsons

Environmental, oxidative, genetic predisposition PARK genes

Parkinsons definition

Presence of bradykinesia, rigidity, rest tremor

Neural structure changes in PD

Degeneration of substantia nigra, cells contain dark pigment neuromelanin

Intraneuronal changes in PD

Lewy bodies have intraneuronal accumulation of protein

PD movement disorders

Resting tremor rigidity, bradykinesia, hypokinesia, freezing of gait, akinesia, postural instability, dystonia

Rigidity

Involuntary resistance to movement in flexor and extensor muscles

Dystonia

Prolonged involuntary muscle contraction affecting specific muscle

PD motor swallowing and speech disorders

Dysphagia, hypophonia, rough voice quality, difficulty commencing speech

Hypophonia

Soft voice due to reduced rom of vocal cords

Emotional and behavioural impairments of PD

Depression, anxiety and apathy

Apathy

Lack of interest or motivation

Cognitive impairments of PD

Impaired recall memory and prospective memory, reduced attention, difficulties in comprehension of complex sentences, figurative and implied information, decreased verbal fluency

Autonomic dysfunction in PD

Orthostatic hypotension, bladder dysfunction, hyperhidrosis, sialorrhoea, sexual dysfunction

Orthostatic dysfunction

Drop in blood pressure with change in position

Hyperhidrosis

Excessive sweating

Sialorrhoea

Excessive salivation

AH assessment of PD - at level of impairment

Movement, communication, swallowing, cognitive, emotional and behavioural disorders

AH assessment of PD - at level of activity

Personal daily living skill, domestic daily living skills, community living skills, communication, driving, indoor and outdoor mobility

AH assessment of PD - at level of participation

Social recreational and leisure activities, capacity for full or part time work

AH assessment of PD - standardised assessment tools

Unified parkinsons disease rating scale UPDRS, assesses ADLs, self care, domestic tasks, communication, motor exam, cognitive, complications of treatment

Pharmacological management of PD 1

Dopamine replacement via Levodopa, precursor of dopamine and is converted to dopamine in the brain, facilitates movement through direct and indirect pathways

Pharmacological management of PD 2

Dopamine agonist, mimics effect of dopamine

Side effects of pharmacological management

Dyskinesia, hallucinations, impulse control disorders

Neurosurgical management of PD - deep brain stimulation

Surgical placement of an electrode deep in brain connected to a battery operated stimulator

Purpose of deep brain stimulation

Useful for people experiencing disabling motor fluctuations, tremors, dyskinesia or dystonia

Target stimulation sites for deep brain stimulation

Subthalamic nucleus, globus pallidus internus, ventral intermediate thalamus

Neural basis of rehab strategies for PD

Goal based learning, practice of specific activities person is having difficulty with, exercise induced neural plasticity, task specific practice with external cues

Huntington’s disease

Neurodegenerative hereditary disease due to genetic mutation in fourth chromosome

Neural structure changes in HD

Cytosine adenine guanine expansion in area that encodes for protein huntingtin, death of neurons in striatum

Movement disorders associated with HD

Chorea, bradykinesia, hypokinesia, rigidity, dysarthria, swallowing

Cognitive disorders associated with HD

Attentional deficits, difficulty with dual tasking

Emotional and behavioural disorders associated with HD

Apathy, anxiety, irritability, decreased awareness of safety

Communication disorders associated with HD

Decreased initiative, decreased complexity

Other disorders associated with HD

Weight loss and sleep disorders

Assessment of people with HD

Swallowing, speech, language, cognition, sports and leisure activities, walking and mobility, postural stability, upper limb function and tasks requiring dexterity, self care, domestic and work tasks, driving