9-18a Postural Control Flashcards
Integrative Care and Practice
What is postural control?
Controlling the body’s position in space for the dual purpose of stability and orientation
What is postural orientation?
The ability to remain appropriate relationships between different body segments (alignment) and b/w the body and the environment for a task
How your body is distributed over the BOS affects alignment
What is postural stability?
one’s balance and ability to control the COM in relation to the BOS; the capacity to move the COM back over the BOS from outside it
Define BOS
area in contact with the support surface
What are the influence of biomechanical factors on postural control?
Ex. How would these effect a unilateral AK amputee?
Higher COM: larger moment arm to topple from BOS; less stability
Lower COM: smaller moment arm to topple from BOS; more stability
If COG/COM are outside the BOS, there is less stability
Wide BOS: more stability
Small BOS: less stability
Define COG
vertical projection of the COM in a 2D plane
Does a higher COM heighten or lower stability?
lower b/c it becomes “top heavy”
larger moment arm
Does a higher COM heighten or lower stability?
lower b/c it becomes “top heavy”
larger moment arm
What is center of pressure?
the center of distribution of the total forces applied to the support surface on a 2D plane
the location of the ground reaction force vector
What does the CNS maintain for COM and COP?
The CNS activates m. to keep COP close to the COM
Define static balance
the ability to maintain the COG within the supporting base while standing or sitting
Define dynamic balance
maintaining an upright position while the COG and BOS are moving/COG is moving outside the BOS
Define dynamic balance
maintaining an upright position while the COG and BOS are moving/COG is moving outside the BOS
Define functional balance
the ability to perform daily movement tasks requiring balance–requires static and dynamic balance
What is the balance between postural stability and orientation dependent upon?
The goal of the task–whether it be to maintain orientation or stability more
What are stability limits?
boundaries within which the body can maintain stability without changing the base of support
What interaction do stability limits result from?
position and velocity of the COM
What interaction do stability limits result from?
position and velocity of the COM
What is the importance of understanding motor control of postural equilibrium and stability
Provide a bases and framework for assessing balance
Provide scientific bases for treating postural control deficits
Being able to predict which patients are at a risk
Being able to predict which patients will improve-and with which interventions
What is the theory behind balance? What systems come together for balance?
Motion stems from the task, the individual, and the environment
What are the components of a postural task during balance?
The steady state, the proactive state, and the reactive state
What are the components of the environment that are a factor during balance?
support surfaces, sensory contact, and cognitive load
What are the components of the individual that are a factor during balance?
Motor (strength), sensory (tactile, visual), and cognitive (strategies and resources)
How does feedforward control relate to posture?
expected postural disturbance coordinates postural adjustment (engaged core)
How does feedback control relate to posture?
unexpected postural disturbance responds with a postural readjustment
