Treatment Principles and Rationale Flashcards
What are the 3 different types of recovery post brain injury?
- Spontaneous
- Behavioural strategies (compensation and learnt non-use)
- Neuroplasticity (network level changes (changes in the pathways that are used), structural level neural repair “true recovery”/synaptic level changes/neural restitution)
What is neuroplasticity?
The ability of neurones to change their function, chemical profile or structure
Underpins learning in the intact brain
Underpins recovery in the damaged brain
Can also have negative maladaptive consequences (e.g. pain, spasticity, learnt non-use etc)
What are the 6 levels at which plasticity can occur?
- Brain level (glial and vascular support)
- Intracellular level (mitochondrial and ribosomal function)
- Biochemical level (protein conformation, enzyme mobilization)
- Genetic level (transcription, transduction, and post translational modification)
- Intercellular /synaptic level
- Neuronal network level
What is neuromodifiability?
Short term changes causes changes in efficiency/strength of synoptic connections
Long term structural changes in the organisation of neurones and the number of connections (which happens over a longer period of time)
What are the names of the two distinct time-dependent patterns of functional changes in the brain that are associated with learning?
Early learning (cognitive) Later learning (automatic)
Describe the neural activity seen in the early learning/cognitive stage.
Activity in widely distributed, predominantly cortical regions; prefrontal, bilateral sensorimotor & parietal cortices
Describe the neural activity in the later learning/automatic stage.
Decrease in neural activity in primary motor cortex
Increased activity in subcortical motor regions, cerebellum & BG
Describe the effect of Braille reading on the cortical sensorimotor representation of the reading finger.
Skilled Braille reading is associated with an enlargement of the cortical sensorimotor representation of the reading finger
Describe the effect of ankle immobilisation on the cortical sensorimotor representation of lower limb muscles
Unilateral ankle immobilisation for 4-6 weeks – significant shrinkage of cortical representation of inactive muscles in participants with LL #
Describe how older adults learn new task
Older adults are able to learn simple and complex novel tasks
Require more training
Pattern of brain activity similar for both groups (older and younger) before and after training but older group recruited more areas
Required greater amounts of activity as older adults had more cortical involvement than younger adults
May explain difficulty with dual tasking
What brain chemical diminishes after 3 months and what is the consequence of this?
Neurotrophic growth factor (NGF) drives recovery. After 3 months recovery is still possible but it takes much longer
What is another name for neural regeneration? Define it.
Regenerative synaptogenesis.
Neuron will send out a a regenerative sprout to re-establish a connection with the neuron next to it (triggered by neurotrophic growth factors (NGF)).
What is the name of the structural level changes that occur during neuralplasticity following a brain injury?
Neural restitution which occurs at the synapse. This is the re-activiation of neural pathways and the restoration of their functions
What is another name for collateral sprouting? Define it.
Reactive synapotogenesis
Neuron grows an axon, which is triggered by NGF, and synapses to the neuron below it
Why are many synapses silent? What does unmasking silent synapses mean?
- As another neural pathway has more receptor sites or not enough neurotransmitter being released and is the preferred pathway
- The alternative pathway is chosen over the preferred pathway
What is denervation supersensitivity?
The growing of receptor sites so it’s more likely to pick up transmission across the cleft. Causes an overreaction and may lead to spasticity and hypertclonus.
How can movement be restored post brain injury?
Through neural restitution/synaptic changes i.e. regenerative and reactive synapatogenesis, unmasking silent synapses and denervation supersensitivity
Define neural restitution. Give an example
A cortical remapping
Changes in the patterns of neuronal activity
A functional recovery is achieved. Damage to the primary motor cortex can cause the pre-motor cortex and the supplementary motor area (SMA) to take over which is not as efficient
What are the 10 principles that maximise plasticity?
- Use it or lose it
- Use it and improve it
- Specificity
- Repetition Matters
- Intensity Matters
- Time Matters
- Salience Matters
- Age Matters
- Transference
- Interference
What does the use it or lose it principle mean?
Neuronal circuits not engaged in task performance for an extended period of time begin to degrade.
Deprivation results in reallocation rather than loss with a reduced representation in the cortex (fewer neurones devoted to that function)
What does the use it and improve it principle mean?
Plasticity is achieved in a brain region by extended skill based training. This improves sensory-motor performance and causes plasticity in the cerebral cortex
What is the principle of specificity?
Skills-based training is better than simple repetition at causing plastic changes in neural connectivity
Must ensure that training is specific to what you want to improve and is challenging
What does the repetition matters principle mean?
Repetition of relearned behaviour may be required to induce lasting neural changes - maximise the number of repetitions each day (practice in and out of therapy)
Despite making behavioural changes, rats trained in skilled reaching do not show changes in synaptic strength, synaptic number or map reorganisation until have performed hundreds of reps (after several days of training)
Clinical implication: Maximise the number of repetitions each day (opportunities for practice in and out of therapy)
What does the intensity matters principle mean?
Induction of plasticity requires sufficient training intensity. Animals performing 400 repetitions/day increase the synaptic number in the primary motor cortex. Ensure patient is practicing in and out of therapy
What does the time matters principle mean?
Different forms of plasticity occur at different times during training. There is a 3 month critical period of hyperexcited state
What does the salience matters principle mean?
Training must be sufficiently salient to induce plasticity
Why does age matter?
Training induced plasticity occurs more readily in younger brains. Neuroplasticity is possible but reduces with age
What does the principle of transferene mean?
Plasticity in one set of neuronal circuits promotes concurrent/subsequent plasticity e.g. it can increase corticospinal excitability and expansion of muscle representation in primary motor cortex
What does the principle of interferene mean?
Plasticity in response to one experience can interfere with the acquisition of memory consolidation. Or it may cause compensatory strategies which lead to learned non-use (which is using compensatory strategies too early)
Interference is a negative consequence of neuroplasticity
If all 12 principles are applied to patients will they recover?
Its rare to get complete restoration to pre-morbid state after a brain injury
What are the 10 principles of treatment post-stroke?
- Use motor learning principles
- Use motor control principles
- Optimise the capacity for meaningful function e.g. repetitive task specific/orientated practice
- Prevent /minimise secondary complications
- Optimise rehabilitation opportunities 24/7 (fun and motivating??)
- Use goal directed interventions
- Provide support, information & advice
- Provide appropriate aids and equipment
- Work as part of the multidisciplinary team
- Evaluate interventions (outcome measures)
Outline motor learning principles
Better outcomes seen with distributed practice over massed practice - as there is time to consolidate learning
Early stage: blocked (progress to random) and constant (progress to variable)
Whole practice: is often not possible - part-task (then progress to whole-task)
Instrinsic feedback is provdied from sensroy cells. Extrinisc feedback: knowledge of results (have you performed the task correctly) - KP (how they will correct it)
Better to give feedback soon after the task rather than during it. Not giving too much feedback so as to not overwhelm the patient
Describe the 3 motor principles
Movement is based on;
- the task the patient is performing,
- the environment they perform it in and
- the patient themselves
Describe the 3rd principle of treatment- optimise the capacity for meaningful practice
Optimise the capacity for meaningful practice - high intensity, repetitous, task specific practice appears to be most effective for recovery of motor function
Why is repetitive task-specific practice important?
- Maximises neuroplastic changes
- The practice needs to be functional as well as repetitive
Name the advantages of part practice
Task is segmented (the task is broken down into parts) and simplifed
important in gait retraining
Why is movement so important?
Sensory input is vitial for maintiang that body part in the cortex. Sensory info is achieved through movement (even passive movement)
What is treatment principle 4 - optimise rehab opportunities?
Its important for physios to ensure the patient is practising outside of their physio sessions as the physios resources are often stretched and cannot give more than 45min of therapy per patient per day. Much of this time may be given towards goal-setting or note-writing
What are the issues in delivering intense rehabilitation?
Resources pressures
Wasted time
Exercise adherence - HEP
How would you optimise rehabilitation?
Goal set
Promote self-efficacy
Engage patients as active participants in their rehab
Get family, friends and other members of the hospital team involved
How would you optimised goal directed interventions?
SMART goals (specific, measurable/motivating, achievable, realistic, timely)
What secondary complications should you aim to prevent?
Pressure sores
Cardiovascualr de-conditioning -> increased risk of falls
Chest infections (common in people with dysphagia)
Contractures
List the complications that pre-dispose patients to soft tissue contractures
Fractures
Immobile with altered tone (TBI)
Unconscious
Patient medically unstable and unable to stand with assistance
Staff shortages
Bank holiday/Christmas
What is a soft tissue contracture?
A loss of ROM due to deconditioning
How can ROM be maintained or increased if there is a risk of contractures?
Stretching + assisted, passive or active movements
Short-term casting/splinting
No stretching in isolation
Medication (Botulinum toxin) for spasticity
What is the national Stroke Guideline recommendations (2016) for post-stroke patients?
Once medically stable patient need to mobilise in/out of bed and chair, standing/walking
This should occur between 24-48hr after stroke
What are the physical activity guidelines for people with stroke or TIA?
What are they for Parkinsons and MS patients?
150min of moderate intensity physical activity in bouts of 10min or more
Muscle strengthening 2 times per week
The same as for stroke patients
MS= 30min of moderate intensity aerobic activity 3 times/week (as MS patients often have a lot of fatigue)
Outine treatment principle 7.
Provide support, info and advice
Promotion of self-management
Education about condition to avoid secondary complications
Outline principle 8 - equipment
Provide aids, adaptations and equipment
May be temporary, permanent or situation-dependent e.g. standing frame, splints, walking aides (frame, stick)
Outline principle 9 and 10
9 = work as part of an MDT
10 = evaluate outcome - select outcome measures that are appropaite to the patient,
valid (measures what it intends to)
reliable (reproducible)
sensitive (able to detect changes), practicable (easy to use in clinic)
