Postural Control (Exam 2) Flashcards
What is postural control (balance)?
Ability to control the body’s position in space with respect to gravity, support surfaces, visual surround and internal references
What is stability?
Ability to control the COM in relation to BOS under static and dynamic conditions
What is orientation?
Relationship between body’s segments, the body and the environment
What are the constructs that affect balance?
- Biomechanical Contraints
- Stability limits/ verticality
- Anticipatory Postural Adjustment
- Postural responses
- Sensory Orientation
- Stability in Gait
What are some other factors to consider for balance?
- Task Complexity
- Environmental Demands
- Cognition
- Perception/ Pusher’s Syndrome
- Confidence/ Balance Self- efficacy
How do we identify balance deficits?
- Observe movement patterns
- Include task progressions or regressions to detect balance deficits
- Include balance outcomes
What are 3 types of balance dysfunction?
- Steady State Postural Control
- Anticipatory Postural Control
- Reactive Postural Control
In the core task of sitting how can you see a deficit in:
Steady State
Anticipatory
Reactive
- This task can test it with no changes
- Add a task or change the environment
- Spontaneous LOB or perturbed
In the core task of sit to stand how can you see a deficit in:
Steady State
Anticipatory
Reactive
- Can’t test
- This alone will test it
- Spontaneous LOB or perturbed
In the core task of standing how can you see a deficit in:
Steady State
Anticipatory
Reactive
- Will test it with no changes
- Task or environmental change
- Spontaneous LOB
In the core task of walk & turn how can you see a deficit in:
Steady State
Anticipatory
Reactive
- Can’t test it
- This will test it
- Spontaneous LOB or perturbed
In the core task of step up & down how can you see a deficit in:
Steady State
Anticipatory
Reactive
- Can’t test
- this will test it with no changes
- Spontaneous LOB
In the core task of reach, grasp, & manipulate how can you see a deficit in:
Steady State
Anticipatory
Reactive
- Can’t test
- this will test it with no changes
- Spontaneous LOB
In regards to Steady State Postural Control what are the determinants and describe what each determinant is?
- Postural Movement Strategies: (related to abnormal postural movement strategies)
- Sensory processing: (Related to abnormal sensory integrity/processing)
- Balance Confidence: (Related to fear of falling/ reduced self efficacy)
- Verticality: (Related to impaired orientation with respect to gravity)
In regards to Anticipatory Postural Control what are the determinants and briefly describe them
- Postural Movement Strategies: (related to abnormal postural movement strategies)
- Sensory processing: (Related to abnormal sensory integrity/processing)
- Balance Confidence: (Related to fear of falling/ reduced self efficacy)
- Executive Function/Multitask Ability: (primarily related to impaired dual task ability)
In regards to Reactive postural control what are the determinants and briefly describe them
- Postural Movement Strategies: (related to abnormal postural movement strategies)
- Sensory processing: (Related to abnormal sensory integrity/processing)
What is the definition of Steady State Postural Control?
Ability to control the body’s COM within BOS under predictable, stable condition
What are two general ways you can test steady state postural control?
- Limits of Stability (how far someone can weight shift outside BOS w/o invoking a strategy)
- Narrow BOS (Romberg)
What is static sitting balance?
Ability to achieve and maintain neural alignment (eyes closed & on foam)
What is Anticipatory Postural Control?
Postural muscle activity anticipates the voluntary movement, ensuring stability of the body during the performance of this task
- Unconscious muscle activity to counterbalance a movement
- Feedforward mechanism
Describe anticipatory postural control in sitting?
- Dynamic Sitting Balance
- Ability to move from & return to a neutral alignment while performing a functional task
- (Ie reaching forward, head turns & actively crossing a leg)
What is Reactive Postural Control?
- Ability to respond to sensory input that signals a need for a response to maintain postural control
- Response is unanticipated (response may be generated internally or externally)
What are the 3 feedback mechanism that may be invoked during Reactive Postural Control?
Ankle Strategy
Hip Strategy
Stepping Strategy
What is an ankle strategy? And when is it invoked?
- Ankle muscle respond to keep COM within the BOS
- Invoked during small, slow perturbance
What is a hip strategy? And when is it invoked?
- Hip muscles respond to keep the COM within BOS
- Invoked during larger, faster perturbation
When is stepping strategy invoked?
When COM falls outside the BOS
A forward ankle strategy would be invoked when and what is the order of muscle activation?
- A push from behind or platform is ripped behind you
- Gastrocs –> Hamstrings –> Paraspinals
A backward ankle strategy would be invoked when and what is the order of muscle activation?
- Push from in front or if platform is ripped infront of you
- Anterior Tib–> Quads –> Abs
A forward hip strategy would be invoked when and what is the order of muscle activation?
- Push from behind or platform ripped from behind you
- Abdominal –> Quads
A backward hip strategy would be invoked when and what is the order of muscle activation?
- Pushed from front or platform ripped from in front of you
- Paraspinals –> Hamstrings
What muscles are activated during a lateral sway?
Hip abductors
Describe the grading of Stepping Strategy
Normals
Impaired
Absent
Normal: recover independently, single large step
Impaired: more than one step
Absent: No step or would fall without assistance
In sitting postural control reactive balance when is a righting reaction invoked?
Slow perturbation
In regards to a righting reaction what happens when reaching above shoulder level on same side?
- Trunk elongates (lengthens/extends) on WB side
- Trunk shortens (flexes) on NWB side
- Head aligns with gravity
When is protective extension invoked in sitting postural control reactive balance? And what is it?
- Fast perturbation
- Results in a reach, abduction of limbs toward downward side