9-18a Postural Control

Question 1

What is postural control?

Answer 1

Controlling the body’s position in space for the dual purpose of stability and orientation

Question 2

What is postural orientation?

Answer 2

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

Question 3

What is postural stability?

Answer 3

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

Question 4

Define BOS

Answer 4

area in contact with the support surface

Question 5

What are the influence of biomechanical factors on postural control?
Ex. How would these effect a unilateral AK amputee?

Answer 5

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

Question 6

Define COG

Answer 6

vertical projection of the COM in a 2D plane

Question 7

Does a higher COM heighten or lower stability?

Answer 7

lower b/c it becomes “top heavy”

larger moment arm

Question 8

Does a higher COM heighten or lower stability?

Answer 8

lower b/c it becomes “top heavy”

larger moment arm

Question 9

What is center of pressure?

Answer 9

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

Question 10

What does the CNS maintain for COM and COP?

Answer 10

The CNS activates m. to keep COP close to the COM

Question 11

Define static balance

Answer 11

the ability to maintain the COG within the supporting base while standing or sitting

Question 12

Define dynamic balance

Answer 12

maintaining an upright position while the COG and BOS are moving/COG is moving outside the BOS

Question 13

Define dynamic balance

Answer 13

maintaining an upright position while the COG and BOS are moving/COG is moving outside the BOS

Question 14

Define functional balance

Answer 14

the ability to perform daily movement tasks requiring balance–requires static and dynamic balance

Question 15

What is the balance between postural stability and orientation dependent upon?

Answer 15

The goal of the task–whether it be to maintain orientation or stability more

Question 16

What are stability limits?

Answer 16

boundaries within which the body can maintain stability without changing the base of support

Question 17

What interaction do stability limits result from?

Answer 17

position and velocity of the COM

Question 18

What interaction do stability limits result from?

Answer 18

position and velocity of the COM

Question 19

What is the importance of understanding motor control of postural equilibrium and stability

Answer 19

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

Question 20

What is the theory behind balance? What systems come together for balance?

Answer 20

Motion stems from the task, the individual, and the environment

Question 21

What are the components of a postural task during balance?

Answer 21

The steady state, the proactive state, and the reactive state

Question 22

What are the components of the environment that are a factor during balance?

Answer 22

support surfaces, sensory contact, and cognitive load

Question 23

What are the components of the individual that are a factor during balance?

Answer 23

Motor (strength), sensory (tactile, visual), and cognitive (strategies and resources)

Question 24

How does feedforward control relate to posture?

Answer 24

expected postural disturbance coordinates postural adjustment (engaged core)

Question 25

How does feedback control relate to posture?

Answer 25

unexpected postural disturbance responds with a postural readjustment