Comprehensive Notes on Parkinson's Disease and Physiotherapy Interventions

Parkinson's Disease: Physiotherapy Interventions

Epidemiology, Pathophysiology, and Etiology

• James Parkinson (1817): First described clinical symptoms:

  • Involuntary tremulous motion with lessened muscular power in parts not in action.
  • Propensity to bend the trunk forward.
  • Transition from walking to a running pace.
  • Senses and intellect remain uninjured.

• Parkinson's Disease Definition:

  • Degenerative loss of dopaminergic neurons in the brain.
  • Characterized by asymmetric Parkinsonism.
  • Demonstrates a clear, dramatic, and sustained benefit from dopaminergic therapy.

• Parkinsonism:

  • A group of disorders with various underlying pathologies causing Parkinson's-like symptoms.
  • Symptoms include slowing of movement (bradykinesia), tremor, rigidity/stiffness, and balance problems.

Types of Parkinsonism

• Parkinson's Disease (Idiopathic Parkinsonism): Most common (approximately 78% of cases).
• Secondary Parkinsonism: Results from identifiable causes:
  • Toxins.
  • Trauma.
  • Multiple strokes.
  • Infections.
  • Metabolic disorders.
  • Drugs.
• Parkinson-Plus Syndromes: Mimic Parkinson's but caused by other neurodegenerative disorders:
  • Progressive supranuclear palsy.
  • Multiple system atrophy.
  • Olivopontocerebellar atrophy.
  • Shy-Drager syndrome.
  • Corticobasal ganglionic degeneration.
  • Dementia with Lewy bodies.

Parkinson-Plus Syndromes: Key Features

• Share symptoms with idiopathic Parkinson's disease (neuronal damage in the substantia nigra).
• Include additional neurologic symptoms not characteristic of Parkinson's disease.
• Clinical features suggestive of Parkinson-plus syndromes:
  • Lack of or reduced response to anti-Parkinsonian drugs (e.g., levodopa).
  • Symmetrical signs at onset.
  • Lack of or irregular resting tremor.
  • Rigidity greater in the trunk than in extremities.
  • Early onset dementia.
  • Frequent falls.
  • Early autonomic symptoms (postural hypotension, incontinence).
  • Visual signs (impaired vertical gaze, nystagmus).
  • Cerebellar signs or motor apraxia.
• Medical differentiation is essential, specifically looking for:
  • Extrapyramidal signs that are bilaterally symmetrical.
  • Lack of response to levodopa.
  • Early onset of dementia or postural instability.
  • Early autonomic signs.
  • Impaired vertical gaze.
  • Motor apraxia.

Prevalence and Statistics

• Estimated prevalence: 7-10 million worldwide.
• Over 110,000 people living with Parkinson's in Australia.
• Most common major movement disorder.
• Second highest neurodegenerative condition in prevalence after Alzheimer's.
• 1 in every 308 people in Australia live with Parkinson's disease.
• Average: 37 new cases are diagnosed every day in Australia.
• Approximately 18% of people living with Parkinson's disease are of working age.
• Prevalence increases threefold after age 65.
• Estimated growth rate of 4% over the next 20 years, compared to 1% in the general population.
• Prevalence higher than many cancers.
• Average time from onset to death: 12.4 years (but can be 20+ years with early diagnosis).
• People with Parkinson's disease are approximately 5 times more likely to be in a residential care facility.

Pathophysiology

• Loss of dopaminergic neurons in the substantia nigra pars compacta of the midbrain.
• Leads to dopamine depletion in the striatum, especially the putamen (motor functions).
• Exaggerated inhibitory influence from basal ganglia to brain regions involved in voluntary movements.
• Accounts for bradykinesia and rigidity, with difficulty activating and relaxing muscles.
• Lack of volitional and automatic movements.
• Both agonists and antagonists are activated when the patient attempts to move.
• Imbalances in other neurotransmitters (cholinergic, glutaminergic) contribute to gait and postural instability.
• Degenerating dopamine neurons develop Lewy bodies (round cytoplasmic inclusion bodies).
  • Consist mostly of misfolded alpha-synuclein protein.
  • Leads to theories of a prion-related hypothesis.
• Basal ganglia dysfunction also leads to:
  • Slow movement or bradykinesia.
  • Reduced movement amplitude (hypokinesia).
• Cingulate cortices involvement contributes to non-motor signs (cognitive, affective, behavioral).
• Brach staging model:
  • Starts in the bowel.
  • Progresses to the medulla and olfactory bulb.
  • Reaches substantia nigra and cortex over time.
  • Non-motor symptoms (loss of smell, sleep disorders, GI symptoms) may precede motor features.

Diagnosis and Clinical Measures

• Diagnosis occurs with the onset of motor symptoms.
• Slow progression, preceded by a subclinical period (approximately 5 years) followed by gradual symptom increase (approximately 13 years).
• Total premotor or prodromal phase of 20 years or more.
• Prodromal phase characterized by non-motor symptoms.
• Axial motor symptoms (postural instability, freezing of gait) occur in advanced disease.
• Progression rate varies; younger age onset and tremor-predominant Parkinson's typically have slower progression.
• Clinical measures:
  • Unified Parkinson's Disease Rating Scale (UPDRS).
  • Hoehn and Yahr classification of disability scale.

Hoehn and Yahr Scale

• Stages severity of disease based on motor signs and functional status.
• Stage 1: Minimal disease impairment.
• Stage 5: Confined to bed or wheelchair.

Unified Parkinson's Disease Rating Scale (UPDRS)

• Comprehensive, accounts for non-motor symptoms (mental functioning, mood, social interaction, cognitive difficulties).
• Assesses ability to carry out daily activities and treatment complications.
• Four parts:
  • Each part has multiple points scored from 0 to 4.
  • Higher total score indicates more disability.
• Modified UPDRS (Movement Disorder Society-Sponsored Revision):
  • Enables clinicians to examine impairments (rigidity, tremor, bradykinesia) and common deficits (cognition, fatigue).

UPDRS Sections

• Part 1: Non-motor aspects of experiences of daily living (intellectual function, mood, behavior).
• Part 2: Motor experiences of activities of daily living.
• Part 3: Motor examination components.
• Part 4: Motor complications.

UPDRS Rating

• Rated on a five-point scale:
  • 0: Normal or no problems.
  • 1: Minimal problems.
  • 2: Mild problems.
  • 3: Moderate problems.
  • 4: Severe problems.

Clinical Stages of Parkinson's Disease

• Preclinical stage: Neurodegeneration present but asymptomatic.
• Prodromal Parkinson's disease: Motor or non-motor symptoms present, but clinical Parkinson's disease criteria not met (can be present for 20 years).
  • Symptoms include reduced or loss of smell, constipation, low mood, and fatigue.
• Clinical Parkinson's disease: Motor Parkinsonism defined by dopamine-responsive motor features.
  • Bradykinesia plus rigidity and/or resting tremor.
  • Presents unilaterally.

Etiology and Risk Factors

• Etiology of idiopathic Parkinson's disease is unknown (combination of genetic and environmental factors).
• Key risk factors:
  • Advanced age.
  • Family history.
  • Exposure to environmental toxins.
  • Head injury earlier in life.
  • Male gender.
  • Beta-blocker use.
• Factors associated with lower risk:
  • Smoking.
  • Drinking coffee and tea (caffeine).
  • Physical activity.
  • Taking calcium channel blockers or non-steroidal anti-inflammatory drugs (except aspirin).

Motor Symptoms

• Bradykinesia: Slowness of voluntary movement, difficulty initiating movements and changing positions.
• Rigidity: Affects proximal musculature early (shoulders and neck), later spreads to face and extremities.
  • Cogwheel rigidity: Jerky, ratchet-like resistance to passive movement due to alternating muscle tensing and relaxing.
  • Lead-pipe rigidity: Sustained resistance to passive movement.
  • Axial rigidity can result in loss of arm-swing during gait and contribute to a cathodic posture.
• Tremor: Initial symptom for approximately 70% of individuals.
  • Involuntary slow oscillation of 4-6 cycles per second.
  • Resting tremor: Present at rest, stops with voluntary use.
  • Pill-rolling tremor: Between thumb and index finger.
• Postural Instability: Not typical in early stages, becomes more prevalent and worsens as the disease progresses.

Secondary Changes and Gait Disturbances

• Reduced muscle strength has been reported across multiple muscle groups.
• Gait disturbances are prevalent in middle to late stages of the disease.
• Reduced velocity.
• Shortened stride length.
• Increased step to step variability and increased double support time.
• Reduced trunk rotation.
• Decreased or absent arm swing.
• Trouble turning (multiple short shuffling steps).
• Widened heel to heel base of support in early stages, typically decreases as the disease progresses.
• Festination: Acceleration and shortening of strides
• Freezing of gait: Sudden temporary inability to move.
  • Start hesitation.
  • Turn hesitation.
  • Hesitation in tight quarters.
  • Destination executive functioning.

Non-Motor Deficits

• Neuropsychiatric symptoms: Depression, anxiety, apathy, cognitive deficits (dementia, executive dysfunction, memory problems).
• Sleep disorders: Restless legs, REM sleep behavior disorder, insomnia, sleep apnea.
• Autonomic symptoms: Orthostatic hypotension, bladder dysfunction, excess sweating, respiratory issues.
• Gastrointestinal symptoms: Dribbling, choking/dysphagia, constipation.
• Sensory impairments: Pain, olfaction disturbance, paresthesia, proprioceptive challenges, visual-spatial issues, anosmia.
• Fatigue.
• Visual changes.

Medical Management

• No cure for Parkinson's disease.
• Medical management aims to slow down progression and treat motor/non-motor symptoms.
• Physician's choice of medications depends on age, symptom presentation, and concurrent health issues.
• Starting medication early has been shown to slow the disease's progression.
• Drugs enhance intracerebral dopamine concentrations or stimulate dopamine receptors (levodopa/carbidopa, dopamine agonists, anticholinergics, monoamine oxidase type B inhibitors, amantadine).
• None of these are considered neuroprotective or disease-modifying.
• Consideration due to the side effects and long complications of dopaminergic therapy, including fluctuations, dyskinesia, and psychosis.
• Fixed medication schedule is important to maintain adequate drug levels.

Dopaminergic Treatment Response

• Bradykinesia and rigidity reliably respond to dopaminergic treatments early in the disease.
• Monoamine oxidase type B inhibitors are only moderately beneficial.
• Dopamine agonists or levodopa needed for more severe symptoms and progressive disability.
• Tremor only responds inconsistently to dopamine replacement therapy.
• Anticholinergic drugs can be more effective for tremor.
• Motor fluctuations include the on off phenomenon and weaning off.

Surgical Intervention

• May be indicated when motor features respond to levodopa, but motor fluctuations and dyskinesia become disabling.
• Deep brain stimulation (DBS) of the subthalamic nucleus or globus pallidus internus.
  • Effective in moderate to severe Parkinson's disease.
  • Thalamic DBS can be effective in treatment of tremor.
  • Can improve non-motor functions, sleep-related symptoms, and behavioral abnormalities.
  • Time to surgical treatment is about 10-13 years after the diagnosis of Parkinson's disease.

Physiotherapy Assessment

• Follows typical neurological assessment process.
• Focus on symptoms causing problems in daily life (tremor, rigidity, etc.).
• Medications, schedule, timing, and effect or fluctuations of the effect over a 24-hour picture.
• Falls: Number, location, timing, associated activities, injuries, near misses.
• Fatigue (Parkinson disease fatigue scale).

Objective Assessment

• Observation at rest for tremor.
• Active range of motion, strength, passive range of motion, and tone (rigidity).
• Trunk rotation.
• Sensation: Screen light touch, detailed review of proprioception, coordination, vision.
• Functional assessment: Bed mobility, transfers, motor control, planning, initiation, bradykinesia.
• Balance and balance reactions.
• Gait: Quality, turning, confined spaces, obstacle negotiation.
• Cardiovascular fitness.

Outcome Measures

• Neurology section of the APTA PD EDGE task force recommends a core set of outcome measures across all stages of the disease as recommended here and grouped by the international classification of function.
• Falls are typically absent in early stages, more prominent in middle stages, and taper off in the later stages as individuals become immobile.
• Approximately 70% of people living in the community with Parkinson's disease will have fallen in the previous year.
• Incidence of limb fractures significantly higher, with about 27% experiencing a hip fracture within 10 years of diagnosis.

Fall Risk Factors

• Disease severity, postural instability, freezing of gait, cognitive impairment.
• Best predictor: History of two or more falls in the previous year (sensitivity 68%, specificity 81%).
• Fear of falling can lead to loss of self-confidence, activity avoidance, and increased independence for mobility.

Physiotherapy Interventions

• Cornerstone is exercise, working on three levels:

  • Movement strategies to bypass defective basal ganglia (planning ahead, focusing attention, avoiding dual-tasking, cueing).

  • Musculoskeletal and cardiorespiratory levels (strength and resistance training, flexibility, aerobic exercise).

  • Quality of enjoyable formats and options such as groups, sports, dance with social contact and interaction.

• Preliminary evidence for physical exercise treatments on brain-derived neurotrophic factor in the blood.

• High dosage exercise also appears to strengthen basal ganglia motor circuits and motor performance by improving glutamate and dopamine agonist neurotransmission, as well as brain health in general.

• Parkinson's disease physical therapy programs should include structured graduated fitness instruction and guidance for deconditioned patients with Parkinson's disease

Physical Exercise Guidelines

• Moderate to high intensity aerobic exercise:
  • Walking on a treadmill or stationary cycling.
  • Improves fitness, reduces motor disease severity, improves functional outcomes.
• Progressive resistance training, with graded resistance exercises used to tackle muscle weakness and associated functional limitations.
  • Improvements in strength or power, improvements in non-motor symptoms (anxiety, cognition, and depression), reductions in motor disease severity.
• Balanced training with benefits including improvements in balance outcomes, improvements in mobility outcomes, and improvements in gait.
• Cueing:
  • The provision of external temporal or spatial stimuli, rhythmic auditory cueing, visual cues, verbal cues or attentional cues.
    • Benefits have been shown for reducing motor disease severity as measured by the UPDRS, reduction in freezing of gait and overall gait outcomes.

Specific Recommendations from Latest Guidelines

• High quality and strength of evidence for moderate to high intensity aerobic exercise.
  • Improves fitness or VO_2, reduces motor disease severity, and improves functional outcomes (gait, balance, ADLs).
  • Most studies: Treadmill walking or stationary cycling.
  • Increased aerobic exercise capacity may improve quality of life.
• High quality and strength of evidence for progressive resistance or strength training.
  • Benefits include Improvements in strength or power, improvements in non motor symptoms, reductions in motor disease severity, improvement in activities such as gait speed, balance, mobility and stability improvements in quality of life and reduction in falls rate.
  • Strength training for greater than eight weeks done at 60% to 70% of the single repetition max has been shown to lead to significant improvements in the six minute walk test, stair to zen time and sit to stand.
  • Can be completed by any number of options, including weighted vests for functional tasks, theraband, hand weights or functional exercises and use of body weight.
• Maintain and improve joint and tissue range of movement (especially extension and rotation) with exercise.

Balance Training

• High quality and strength of evidence for balance training.
  • Benefits include Improvements in postural control, improvements in balance outcomes, improvements in mobility outcomes.
  • Exercises need to be individualized to deficits and must be challenging/progressive.
  • May include addressing flexibility/joint mobility for posture, weight shifting activities, self-destabilizing, external destabilization, activities combined with walking, obstacle negotiation.

Cueing Strategies in Parkinson's Disease

• High quality evidence for cueing (external temporal or spatial stimuli).
  • Rhythmic auditory cueing, visual cues, verbal cues, attentional cues.
  • Benefits: Reducing motor disease severity, reduction in freezing of gait, and overall gait outcomes.
• Individuals respond well to cueing to increase movement amplitude and velocity (visual and auditory).
• Typical Methods:
  • Visual cues on the floor.
  • Lasers attached to walkers and canes.
  • Special glasses that places a visual stimulus in front of the viewer.
  • Use music counting to set the step cadence.

Rhythmic Auditory Cueing

• Early incorporation is strongly recommended for enhancing gait performance.
• The body of evidence supporting its use includes improved scores on the dynamic gait index, improved teneti mobility test scores and improved freezing of gait questionnaire outcomes.
• Training should include tempo variations of plus or minus 10% of the preferred cadence for twenty to forty minutes per day for at least three to five days per week.
  • Home practice is required and smartphone apps may be a useful option.

Gait Training

• High quality and strength of evidence.
  • Benefits include to reduce motor disease severity, improve stride length, improve gait speed, general mobility and balance.
  • Lasting benefits are achieved with forty five to sixty minutes of practice per session, two to three times per week for at least eight weeks.
• Treadmill training with or without body weight support, and thus the use of a harness is only recommended when needed to ensure safety.
• Step length includes treadmills with virtual reality to provide external cueing, robotic assisted gait training, with queuing.

Assistive Devices.

• Are commonly prescribed to improve safety and decrease falls.
• Forward rollator walkers allow people with Parkinson's disease to achieve the highest walking velocity, least stumbles and falls during turning and most consistent stepping
• For some individuals with Parkinson's disease, they tend to walk with a forward propulsive gait, resulting in their upper body moving forwards over their lower body during gait. These individuals tend to respond well to a forward walker with reverse brakes.
• Reverse brakes require the user to squeeze the hand brakes to release them and let go of the brakes to apply them.
• Walkers with laser pointers for visual cueing as well.

Task-Specific Training

• High quality evidence for task-specific training to improve task-specific impairment and functional outcomes.
• Transfer training should be completed with mental imagery.

Sit-to-Stand Training

• Patients have difficulty getting their weight forward over their feet and thus have increasingly more difficulty as the surface that they are transferring from is lowered.
• Critical to have the patient lean forward while keeping their head up with an erect spine.
• Use of the hands on the knees can help encourage a forward weight shift as well as providing upper extremity assistance for the transfer.
• Bending forward with a flexed spine increases the difficulty of straightening up at the end of the transfer and can result in the person with Parkinson's disease becoming stuck in a flexed posture.

Complementary Interventions

• Falls prevention
• Aquatic therapy
• The promotion and use of self-management
• Dance therapy
• Virtual reality training and computer-based gaming
• Tai Chi and yoga

Fall Prevention

• Appropriate therapy can reduce falls risk scores on common falls risk assessment tools, and at least one study found a trend that fall number was reduced
• It is clear that preventing falls requires individualized interventions that include balanced training and additionally that interventions need to be based on each individual's unique impairments and situational factors.

Aquatic Physiotherapy

• There was an improvement in motor disability and it was also found to be feasible and safe.
• Is a valid, safe and feasible method to increase exercise and physical activity levels in Parkinson's disease.

Self-Management

• Assisting and educating people with Parkinson's disease and their families and carers about what they can do to assist to manage their symptoms and limit as best possible their disease progression.
• Means assisting and educating people with Parkinson's disease and their families and carers about what they can do to assist to manage their symptoms and limit as best possible their disease progression.

Music-Based Movement Therapy / Dance

• Combines cognitive, cueing, and balance strategies with physical activity.
• Uses music as an auditory cue for movements.
• Several forms investigated: Partner Tango and non partner dancing.
• Several mechanisms have been proposed underlying the observed improvement following dance therapy.
• Dance movements are intensive enough, they also impose a considerable demand on aerobic capacity and induce a training effect for endurance.

Virtual Reality and Video Games

• Help improve motor status with engagement.
• Requiring the therapist to carefully analyze the game to be prescribed and each individual's ability to play each of the different games.
• Exergaming is an emerging tool to help some people with Parkinson's disease (more research needed to establish its safety and clinical effectiveness).

Tai Chi

• Has a statistically significant effect on the outcomes of gait velocity.
• Feasible intervention for potential different clinical applications.

Yoga

• Patients in the yoga training group had better functional outcomes in terms of motor status, balance function, functional mobility, anxiety scores, depression scale scores and quality of life.
• Overall, the results showed the benefits of yoga in improving motor function, balance, functional mobility, reducing anxiety depression and increasing quality of life in Parkinson's disease patients.