Week 3 Flashcards
What is postural control?
Involves controlling the body’s
position in space for stability and orientation
What is postural orientation?
Ability to maintain appropriate
relationship between body segments and between body and environment for a task
What is postural stability?
Ability to control the center of mass (COM) in relationship to the base of support (BOS)
What is Center of Mass (COM)?
Point at center of total body mass, determined by finding weighted average of the COM of each body segment
What is Center of Gravity (COG)?
Vertical projection of COM
What is Base of Support (BOS)?
Area of body that is in contact with support surface
What is center of Pressure?
Center of the distribution of the total force applied to the supporting surface. COP moves continuously around the COM to keep COM within support base
All tasks require __
All tasks require postural control
Every task has an ___ component and a ___
component
Every task has an orientation component and a stability
component, and each varies with the task and the environment
The relationship between orientation and stability is ____
Inverse
What does postural control emerge from?
An interaction of the individual, the task with its inherent postural demands, and the environmental constraints postural actions
What are the components of balance?
- Postural tasks
- Individual
- Environment
What are the motor components of posture and the individual?
Musculoskeletal, muscle synergies
What are the sensory components of posture and the individual?
Sensory systems, sensory organization
What are the cognitive components of posture and the individual?
Cognitive strategies, cognitive resources (cognitive doesn’t necessarily mean conscious control)
What is included in the cognitive components of posture and the individual?
Attention, motivation, intent; also ability to adapt in response to changing demands, anticipatory aspects of postural control based on previous experience and learning
What is the relationship between task being handled at once and attention available for posturing and balance?
Inverse, the more task being being handled at once, the less attention available for posturing and balance
What are the support surfaces components of posture and the environment?
Changing support surfaces affects organization of muscles and forces needed to balance
What are the sensory context components of posture and the environment?
Differences in visual and surface conditions affect way sensory info used for balance
What are the cognitive load components of posture and the environment?
Multi tasking affects the way things like attention are used for balance
What may the attention required for postural task lead to?
May reduce performance of second task
What is the definition of postural task: steady state?
Ability to control COM relative to BOS in fairly predictable, stable and non-changing conditions
What is the definition of postural task: proactive?
Ability to activate muscles in legs and trunk for balance control in advance of potentially destabilizing voluntary movements. Relies on feed forward condition (anticipatory posture for destabilization)
What is the definition of postural task: reactive?
Ability to recover a stable position following an unexpected perturbation. Relies on feed back mechanism
What are the contributions to postural control?
- Body alignment
- Muscle tone
- Postural tone
How does body alignment contribute to postural control?
Minimizes effect of gravitational forces
How does muscle tone contribute to postural control?
Keeps body from collapsing in response to pull of gravity
How does postural tone contribute to postural control?
Keeps body from collapsing in
response to pull of gravity. The activation of the anti-gravity muscle
Where is fixed support recovery of balance?
- Ankle
* Hip
When is ankle strategy used?
In small perturbations. Requires good ROM of the ankle
When is hip strategy used?
When the perturbation is larger and or faster, and when the BoS is concurrent or smaller than the feet
When is the change in support recovery of balance used?
When there is a change in BoS
What is the stepping strategy?
Re- aligning the BoS under a falling CoM. Always preceded by a medio-lateral anticipatory postural adjustment. Before you can take a quick step, there has to be a shift in CoM in one direction or the other
Who are those that will find the stepping strategy very difficult to accomplish?
Patients with decreased ability to weight shift over their BoS. (stroke or weakness due to injury. will do for reach-to-grasp instead)
How does the reach-to-grasp strategy work?
By extending the BoS by using the arm
____ makes it possible to ensure that the forces generated from one point doesn’t produce instability in the other parts of the body
CNS makes it possible to ensure that the forces generated from one point doesn’t produce instability in the other parts of the body
What do postural muscles activated before voluntary
movements do?
Minimizes disturbance to balance
What do visual, somatosensory, and vestibular systems that provide info about body position and movement in space with respect to gravity and environment do?
Each provide different frame of reference for postural control
What are the spinal contributions to controlling postural orientation and stability?
Tonically active extensor muscles for antigravity support in postural orientation; somatosensory contributions to postural control
What are the brainstem contributions to controlling postural orientation and stability?
Level of postural tone, automatic postural synergies that occur during poor posture, vestibular contributions to postural control
What are the basal ganglia contributions to controlling postural orientation and stability?
Postural Set (ability to quickly change muscle patterns)
What are the cerebellum contributions to controlling postural orientation and stability?
Control of adaptation (ability to modify postural muscle amplitude)
What are the consequences of impaired stability?
- Loss of functional independence
- Reduced or restricted participation
- Reduced confidence
- Increased fall risk
What are the characteristics of alignment as a problem in motor systems?
Often changed in persons with neuromuscular dysfunction
What are the characteristics of postural sway as a problem in motor systems?
Increased postural sway area and velocity; asymmetrical sway area. Sway areas will be biased towards the active area
What are the characteristics of functional stability limits as a problem in motor systems?
Reduced limits of stability
(reduced COP excursion). Inability to move CoP over the BoS, causes instability
What are the characteristics of steady-state balance in sitting as a problem in motor systems?
All about control of trunk
segmentally; good prognostic indictor of outcome following stroke and TBI.
What are the components of impaired reactive balance?
- Sequencing Problems
- Coactivation
- Delayed onset of postural responses
- Problems modifying postural strategies
- Impaired central set
What are sequencing problems?
The inability to sequence firing muscle. Simply messes with the sequence with which the needed muscles are activated
What is central set?
The ability to adapt quickly to changes in task and or the environment. Gets impaired due to neurological injuries
What are the components of impaired change in support strategies?
- Lack of anticipatory lateral weight shift
- Delayed onset of support strategy
- Take many steps to recover
When is anticipatory lateral weight shift critical?
Before any stepping strategy can occur.
What are the components of impaired anticipatory postural control?
• Heavily dependent on previous experience and
learning
• Lack of anticipatory activation in “affected side” in stroke, brain injury
• Lack of anticipatory trunk activation
• Seen with lesions in many areas of nervous system
- Circuitry for anticipatory postural control involves
supplementary motor cortex, basal ganglia, and cerebellum
What are the characteristics of sensory problems that can affect reactive balance?
- Triggers centrally organized postural synergies
- Providing direct sensory feedback to scale magnitude of automatic postural responses. This ensures that the sensory response given is proportionate to the instability/imbalance felt
What are the characteristics of sensory problems that can affect anticipatory balance?
- Profound changes in motor adaption
* Earlier activation of anticipatory postural adjustments (compensation)
What are the characteristics of perceptual problems that can affect postural control?
• Perceptions of verticality: often impaired in stroke,
correlates with poor balance
What are the characteristics of balance and falls self-efficacy as a problem in cognitive systems?
- Confidence in ability to perform activities without losing balance or falling
- Lack of self-efficacy is common in persons with neuromuscular dysfunctions
What are the characteristics of impaired postural stability and dual-task interference as a problem in cognitive systems?
- Amount of attention required depends on difficulty
- Impaired postural control increases attentional demands of balance
- Less reserve for other tasks
What is agnosia?
An inability to recognize or perceive familiar sensory information even though the sensory system is without deficit.
Disturbance of one of the sensory modes of visual,
tactile, proprioceptive, and auditory, or may involve
problems in body scheme
What is visual agnosia?
• Perception without meaning, inability to recognize visual stimuli despite adequate visual functioning • Failure to recognize familiar colors, objects or name them using vision
What is prosopagnosia?
Failure to recognize people or faces. Highly uncommon
How is the evaluation of agnosia done?
• Rule out sensory deficit and
anomia
• Object recognition
• Visual Identification of Objects
How do we manage visual agnosia?
- Use real objects
- Physical guidance
- Practice discrimination between objects
- Compensate with other sensory modalities
What is auditory agnosia?
Failure to identify meanings of sounds, cannot discriminate between speech and non speech sounds
How do we manage auditory agnosia?
Drilling or practice compensate with other sensory modalities (usually done by speech
pathologist)
What is tactile agnosia?
Astereognosis- inability to recognize objects by handling them even though the tactile sensations are without deficit
How is tactile agnosia evaluated?
• Place objects in hand, have pt hold it, then remove it
and place on a tray; have pt show you which object he
had in his hand
• Ayres’ Manual for Perception: 10 plastic geometric forms placed in clients hand and they are to identify the object by finding it on a chart
How do we manage tactile agnosia?
Practice or compensation(visual is the most common)
What is apraxia?
An inability to perform voluntary purposeful movements even though the sensory, motor, and cerebellar systems are without deficit. It is
a motor programming disorder. Misuse of objects or using them in an incorrect manner
What is ideomotor apraxia?
The inability to produce gestures or perform a purposeful motor task on command even though the person understands the concept of the task. Occurs when there is a failure to transmit the plan of action and convert it to a motor movement in the frontal lobes.
What is ideational apraxia?
Patient is unable to formulate a plan of action. They cannot develop the sequence or create the motor patterns necessary to execute the task. They cannot describe the task or items that would be used to
complete the task
What are the differences between ideomotor and ideational apraxia?
• Pt with ideomotor apraxia will not be able to do an activity
to command, but will be able to do it automatically at the
appropriate time
• Pt with ideational apraxia could not do the task at all even though they have the motor capacity to do it (or complete it incorrectly)
What are the general guidelines for the evaluation of apraxia?
• Perform a detailed sensory and physical functioning
assessment
• Evaluate visual agnosia to rule out object recognition
problems
• Evaluate both UE/LE
• Does the pt seem bothered by the errors they have
made or can they recognize the errors
What are the characteristics of different assessments for apraxia?
• Dynamic Assessment: task range from simple to complex; peel a banana, butter bread and cut in half, pour soda into a glass and drink with a straw, fit letter into an envelope and put a stamp on it, make a bowl
of cereal
• Multi-Level Action Test: 3 tasks; making a slice of toast
with butter and jam, wrapping a present, and packing
a lunchbox.
What are the management methods for apraxia?
• Keep verbal commands to a minimum, put task at
subcortical(automatic) level, physically guide, visualize the task.
• Performance can improve with imitation and
repetition
• Use simple or isolated tasks
• The more familiar and typical the surroundings the
better (good argument for home health)
• Use cue (picture) cards taped to objects required for everyday function, stating what the object is and how to use it
What is constructional apraxia?
Impairment in producing two or three dimensional designs, whether copying, drawing or constructing. The impairment cannot be attributed to ideomotor apraxia or a primary motor impairment. Unable to understand the relationship of the parts of a task or object to the whole.
What causes constructional apraxia?
Lesion of the right cerebral hemisphere
What are the characteristics of constructional apraxia?
• May be related to body scheme problems
• People who did poorly on block design tests and
object assembly tests did not acquire dressing and
grooming skills
• Management: practice simple construction of tasks
and progress to more complex, use physical guidance, backward chaining
What is backward chaining?
Start with a completed project and work in reverse
How is constructional apraxia evaluated?
- Copying designs-House Test, Clock Test
- Copy Shapes
- Block Design
- Peg Board Design
How is constructional apraxia managed?
- Practice simple construction of tasks and progress to more complex
- Physical guidance
- Backward chaining
What is unilateral neglect?
Inability to perceive and integrate stimuli and perceptions from one side of the body, even though the sensory system is normal and visual system intact
What side does unilateral neglect usually involve?
The left side (right parietal cortex damage)
What does a left hemisphere/ parietal cortex damage lead to?
Minimal right neglect
What does a bilateral parietal cortex lesion lead to?
Severe right neglect
How do we manage neglect?
- Increase stimulation to side of brain being neglected
- Bilateral movements with weight bearing
- Forced use
- Compensate with visual scanning
- Verbal cueing
- Adapt the environment
What is somatagnosia?
• Lack of awareness of body structure and failure to
recognize how parts relate to each other and the whole body
• Inability to identify any part of one’s own or another’s body
What is the clinical presentation of somatagnosia?
Patient might complain of their arms being heavy, with a lot of difficulties in dressing
How do we manage somatagnosia?
Provide tactile input, identification of body parts, bilateral activities. It is critical to keep instructions very simple
What is right and left disorientation?
Complex neuropsychologic process that uses several
higher functions, including visuospatial processing, memory, language, and integration of sensory information
What causes right and left disorientation?
Damage to parietal lobe at angular gyrus
What is the presentation of right and left disorientation?
Inability to distinguish right and left
Right and left disorientation is one component of Gerstmann’s syndrome, what are the others?
- Acalculia and discalculia: Inability to solve small maths problems
- Agraphia and disgraphia:
What is anosognosia?
Inability to recognize and a refusal to accept the presence or severity of one’s own paralysis (Denial). Typically transient and may be associated with decreased mental and intellectual functioning.
How do we manage anosognosia?
Very difficult, they may refuse any compensations or activities
What are spatial relations disorders?
- Inability to appropriately discriminate the body in relation to two or more objects or directions
- Inability to detect relationship of objects or self to objects in space
What is figure ground discrimination?
Inability to visually distinguish an object from the background in which it exists or locate an object that is not prominent in the visual array
What is the clinical presentation of figure ground discrimination?
Cannot find things in a cluttered drawer, white shirt on white sheet, locate shirt
buttons
How do we manage figure ground discrimination?
Compensation with visual scanning, amplify stimulus, simplify/adapt the environment, and repeated practice
What is topographical disorientation?
Inability to perceive the concepts of up, down, in , out, in front of, etc. Difficulty identifying certain landmarks
What is the clinical presentation of topographical disorientation?
Difficulty getting from one place to another
What are the management options of topographical disorientation?
Practice, mark route with colored dots on a neighborhood map
What is depth and distance perception?
Inability to perceive and judge direction, distance, or depth. Difficulty in identifying change in surfaces
What are the management options for depth and distance perception?
Can use specialized glasses, practice, adapt environment
What is vertical disorientation?
Distorted concept of what is vertical
___ highly associated with pushing after Right hemisphere damage
Neglect highly associated with pushing after Right hemisphere damage
____ highly associated with pushing after Left hemisphere
damage
Aphasia highly associated with pushing after Left hemisphere damage
What is the anatomy associated with pusher syndrome?
Left or Right Posteriolateral thalamus
What is the posterolateral thalamus’s role in vision?
Provides info about movement and cues for judging upright posture
What is the posterolateral thalamus’s role in vestibular?
Informs person about head position relative to gravity and about head movement
What is the posterolateral thalamus’s role in somatosensation?
Provides information about
weight bearing and relative position of body parts
What is graviception?
Perception of body position, equilibrium, and direction of gravitational forces
Pusher syndrome is the distortion of ____
Subjective postural
vertical
Patients with pusher syndrome experience a mismatch between ___ and ____
Patients with pusher syndrome experience a mismatch between visual and postural vertical, Visual vertical based on vestibular AND visual inputs
What are the prognosis of pusher syndrome?
• Does not affect functional outcomes
• Rarely still evident at 6 months
• BUT.. It does slow process significantly
• Need 3.6 weeks longer to reach same functional
outcome as those without pusher syndrome
- Goal should be to shorten rehab time
• Pushing can be fairly well compensated for by brain,
as compared with aphasia or neglect
• Those with R CVA and pusher syndrome significantly worse
What are the test conditions of the Modified SCP (M-SCP)?
- Static sitting at bedside, feet on floor
- Static standing with a full erect posture
- Transferring from bed to chair or wheelchair with squat pivot
- Transferring from bed to chair or wheelchair using stand pivot
What is the recommended measure for pusher syndrome?
BLS recommended for identifying contraversive
lateropulsion
• Across several functional tasks (rolling to walking)
• Only scale originally written in English
• Best reliability and responsiveness
What are some of the current evidence of treating pusher syndrome?
• Treat in earth vertical positions (sitting, standing,
walking)
• Allow pushing to occur so pt experiences falling
• Make pts visually aware of tilted position
• Assist with active correction
• Reaching vertical position actively
• Trained to use visual orientation
- Are you upright?
What are the characteristics of visual feedback treatment for pusher syndrome?
• Realize the disturbed perception of erect body
position
• Visually explore the surroundings and the body’s
relation to the surroundings
• Learn the movements necessary to reach a vertical
body position
• Maintain the vertical body position while performing
other activities.
What are some activities for the pusher?
• Patient needs to see that they are or are not oriented upright - Use of vertical structures • Active reaching (goal directed) to temporarily extinguish pushing • Managing transfers - Forward weight shift is key - Which side do we go to? • Blocking the unwanted movement
What are the pathways of postural control?
- Reticulospinal Tract
- Vestibulospinal Tract
- Medial Corticospinal Tract
What are the effects of a SCI on posture?
- Varied Muscle Activation
- Delayed Responses
- Tone and Spasticity
- Bracing
What’s the biggest difference in postural control in the SCI
versus able-bodied population?
- Sporadic Muscle Activation
* Varied Trunk Control
If you put a vertical line through the side of a person with normal posture, what structures does it bisect?
Ear, acromion, greater trochanter, L3-4, and lateral malleolus
What are some postural control techniques?
• Obtain normal alignment • Upright in sitting - Easy first position - Can use UE for support • Progressing to standing if able • You may need more than 2 hands
What are some ways to challenge our patients once they have achieved normal posture?
- Alter BOS
- Alternating UE support
- Alternating support surfaces
- Altering sensory inputs
What are some ways to challenge our patients with dynamic tasks once they have achieved normal posture?
- Ball Toss
- Reaching Activities
- Unsupported Exercises
- Sports and Games
What are the biggest risk factors in the SCI population?
- Autonomic Dysreflexia (T6 or above)
* Orthostatic Hypotension
What is autonomic dysreflexia?
A rapid increase in BP due to some noxious stimuli. Gradually move them into a standing position and try to figure out what the problem is
What is the greatest risk factor for exercise in SCI?
Therapist
What is scoliosis secondary to?
Poor posture (sitting position) and abnormal muscle activation (iSCI or spasticity)
How do we manage scoliosis?
- Stretch tight muscles/ mobilize structures
- Position into proper vertebral alignment
- Stabilize in proper alignment and perform core stability exercises in the alignment
- For SCI, begin in sitting and work your way up
What does instability look like?
Problems with: • Static posture • Dynamic mobility • Joint stability • Maintaining a weightbearing position • Closed chain and open chain actitivities
What are the basics in determining the best treatment for our patients?
- Identify the limitations in function
- Determine the specific underlying impairments
- Prioritize the problems in an effective plan of care
What are the questions that we have to think of during our examination of a patient with instability?
- How is instability impacting function?
- What is impact of this instability on specific movement components? On the rest of the body? Above and below instability?
- What is the likely cause versus the consequence?
- What other systems are involved?
- Tests and measures?
- Impairment measures?
What are the questions that we have to think of during our evaluation of a patient with instability?
• Is instability direct cause of functional limitation?
• What are contributing factors? What are
consequences of instability?
What are the things to think about when deciding on the intervention for instability?
- First determine remediation versus compensation or both
* Address barriers: joint mobility, muscle length, strength, sensory awareness
What are some specific interventions to address stability?
- Resistance exercise
- Stance weightbearing exercise
- Postural exercise
- Biofeedback/Estim
- Taping/strapping
- Splinting/bracing
- Pressure garments
- Body weight supported treadmill training
What are the main approaches to visual field loss?
- Adaptation/compensatory – more favorable option
- Substitution
- Restitution: actual restoration of visual loss
What are the components of compensation as an intervention for visual field loss?
Scanning and search training
What are the components of restoration as an intervention for visual field loss?
Light stimuli to border area of visual field loss to increase visual field
What are the components of substitution as an intervention for visual field loss?
Peli prism: high strength prism placed above or below the pupil and they will reflects the images from the impaired visual field to the intact one
What is strabismus?
Misalignment of the 2 eyes (both eyes don’t point to same target)
What causes ocular abnormalities?
Cranial nerve problems
What are some interventions for ocular motility deficits?
• Pharmacological - Botox, used as an assessment prior to surgery
• Compensatory – occlusion to eradicate 2nd image; adaptive head postures and increase in lighting
• Substitutive – Prisms to reduce diplopia
• Restorative – vergence exercises or in more chronic
cases with ocular muscle surgery
What is reduced central vision?
Reduced visual acuity and contrast sensitivity
What are the treatment options for reduced central vision?
Retest vision after BI, adjust glasses; low vision aids like magnifiers; modification of light and environment
What are visual perceptual deficits?
Visual inattention/neglect
What are visual perceptual deficits treatment methods?
• Substitutive: perceptual retraining and visual scanning
• Compensatory: scanning therapy, ADL training and
provision of aids and modifications; smooth pursuit
training
What are the different ways to screen for visual deficits?
• Visual acuity • Contrast sensitivity - Pelli-Robson Contrast Sensitivity Test • Visual Fixation/Attention Testing - See during visual tracking - Warren Fixation Test • Ocular Alignment/Range of Motion Testing - Double H - Convergence • Depth Perception - Straw and stirrer test • Visual Field: - Peripheral testing - Confrontation testing (test one eye at a time) - Tests for neglect
What is the role of the PT in visual deficits?
• Detection of a problem
• Consultation and referral
- Neuro optometry
- Neuro othalmology
What are the characteristics of the Postural Assessment Scale for Stroke (PASS)?
• 12 item performance based measure of postural
control
• Specifically sensitive in first 3 months
• Measures ability to maintain stable postures and
equilibrium during positional changes related to sitting, laying down and vice versa
• 10 minutes to administer
• No special equipment
What are the characteristics of the Function in Sitting Test
(FIST)?
- 14 item test
- Developed and validated for adults with acute stroke
- Easy to administer
- Performed at bedside
What are the characteristics of the Static Standing Test?
• 5 standing positions, no UE support, goal is to maintain at least 30 seconds • Feet apart (10 cm) • Feet together • Stride stance (10 cm) • Tandem stance • Single leg stance
No cut offs
What are the characteristics of the Trunk Impairment Scale?
- Static sitting balance
- Dynamic sitting balance
- Coordination
- All done from pt sitting on edge of bed or mat
