Balance / Assessment Flashcards
Goals of the postural control system
-maintain a steady stance
-anticipate volitional goal directed movements
-adapt to changing requirements
Components of the postural control
-motor
-sensory
-central processing (awareness, attention, automatic reactions)
Postural control is achieved by continually …..
positioning the body’s center of gravity over the
base of support during both static and dynamic situations
Balance is simply defined as
keeping the center of gravity within the base of support in a given environment
Deficits within any single component of balance are typically not sufficient to cause postural
instability, because….
However,
compensatory mechanisms from other components prevent that from
happening
deficits across multiple components may lead to instability and falls
The balance system consists of a complex set of control process that can be divided into
two distinct and interdependent systems
Gaze and postural
the gaze stabilization system maintains
gaze direction and visual acuity during activities involving active head and body movements
postural stabilization system function
keeps the body in balance for static and dynamic
activities
a rapidly acting system that reflexively drives eye
movements that are equal and opposite to those of the head.
VOR (vestibule-ocular reflex)
The 2 components of the balance system are
interdependent
Does the VOR require visual information?
What is it influenced by?
Is it effective in slow movements?
-NO
-the individuals state of arousal
-NO
VOR is effective for stabilizing gaze during
rapid movements
allows the direction of gaze to smoothly follow a
visual target during active movement
smooth pursuit eye movement system
What does the smooth pursuit eye movement system require
it is not affected by
it dominates during
the presence of a visual target
the absence or presence of vestibular info
slow movements
When
the VOR and smooth pursuit systems fail to maintain gaze on the target
saccadic eye movement system can generate rapid catch-up eye movements
when gaze is
first directed to a new visual target
saccadic eye movement system can generate rapid catch-up eye movements
The saccadic eye movement system requires
it is not affected by
the presence of a visual target
and is not affected by vestibular information
Maintaining postural stability is a more complex balance process that relies on the
interaction of three major components
- vision, vestibular, propio, contact with support surface in combo
- motor reactions among muscles
- integration of sensory and motor info and adaptation of env
Alignment contributes to postural stability by
allowing the body to remain in equilibrium
with the least amount of energy
Factors that influence postural tone
include
activation of cutaneous receptors against a surface, visual, and vestibular inputs.
During upright posture, there is background activity in the
anti-gravity muscles, which is termed
postural tone
Muscles that tend to be tonically active during stance include
the gastrocnemius and soleus,
tibialis anterior, gluteus medius and tensor fascia lata, iliopsoas, thoracic erector spinae,
and intermittent contractions of the abdominals.
There are five basic strategies that have been identified as responses to unexpected
postural perturbations.
2 hip is?
What is the pattern?
Who tends to use this more?
A hip strategy is the activation of muscles around the hip joint as a result of a
sudden and forceful disturbance of the base of support or a perturbation to balance
while standing on a narrow support surface
proximal to distal
older adults
There are five basic strategies that have been identified as responses to unexpected
postural perturbations.
1 ankle strategy is?
What is required?
An ankle strategy is the activation of muscles around the ankle joint after a small
disturbance of the base of support when standing on a firm, level support surface
significant amount of ankle strength and mobility
There are five basic strategies that have been identified as responses to unexpected
postural perturbations.
3 stepping is?
The stepping strategy has been defined as taking a step rapidly in the direction of
the movement of the center of gravity, which has been displaced beyond the limits
of the base of support.
There are five basic strategies that have been identified as responses to unexpected
postural perturbations.
4 reaching is?
Has a significant role in?
The reaching strategy includes moving the arm to grasp or touch an object for
support
preventing falls