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Balance & Equilibrium
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Balance
 Ability to align body segments against gravity to
maintain or move the body ( center of mass)
while a static & dynamic movement within the
available base of support without falling.
The ability to move the body in equilibrium with
gravity via interaction of the sensory and motor
system
 Process of maintaining body’s COG within base
of support
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Postural equilibrium - broader term that incorporates alignment of
joint segments
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Maintaining COG (Center of Gravity) within the limits of stability (LOS)
Limits of Stability ( LOS)
N.B:
- Limits of Stability ‘LOS” is defined as the distance a person can move,
without losing balance or taking a step.
 Factors
impacting balance
 Muscular
weakness
 Proprioceptive deficits
 ROM deficits
Postural Control System
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3 Components of the system
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Sensory detection of body motions
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Visual
Vestibular
Somatosensory inputs
Integration of sensorimotor information within the CNS
Execution of musculoskeletal responses
Balance is both a static & dynamic process
Types of Balance
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Static balance :ability to maintain postural stability on
a stable surface or when not engaging in locomotor
activities
Dynamic balance : ability to maintain postural stability
on a moving surface or when engaging in locomotor
activities
Factors affecting the balance
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- Muscular strength
 Fatigue of the Lower Extremity muscles
 With age strength decreases, which results in a decline in balance
- CNS
 Injury to the brain or spinal cord might interrupt communication between the
body part/system & the CNS
- Medications
 Some drugs could affect the balance
- Pathological changes to vestibular & visual systems
 Subject with vestibular defect/injury might present with:
- Gait alterations & decreased static balance
- Limited control of the COG within the base of support
- Age
 medial-lateral balance declines with age in women, especially between the ages
of 40 & 60
- Size of the base of support (BOS)
 Smaller BOS requires finer body adjustments to maintain balance
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- Injuries to the Lower Extremity
 Normal alignment & stability of the supporting Lower
Extremity decreases friction; which contributes to the
smoothness of gait
 May result in inefficient energy expenditure during walking
or running
 May lead to the COG to fall outside of the BOS – increase
risk of falling
 Balance impairments have been related to risk of injury
&/or risk of re-injury
 May damage joint proprioceptors which contribute to
maintaining balance
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Obesity
 Obese person spent significantly greater time in the
double support phase & may have less dynamic &
static balance
 Thigh
mass of obese individuals may be
disproportional to the rest of the body, results in an
increase in leg mass & affects the internal work of
the muscles
Balance requires input from
-Visual system
-Vestibular system
-Proprioception
Muscular strength, endurance & flexibility
Control of Balance
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Balance relies on network of neural connections
Postural control relies on feedback
CNS involvement
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Sensory organization
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Determines timing, direction & amplitude of correction based on
input
System relies on one sense at a time for orientation
Muscle coordination
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Collection of processes that determine temporal sequencing &
distribution of contractile activity
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Sensory Input
 Vision
 Measures orientation of eyes & head in relation to surrounding objects
 Helps maintain balance
 Vestibular
 Provides info dealing with gravitational, linear & angular accelerations of
the head with respect to inertial space
 Minor role when visual & somatosensory systems are operating correctly
 Somatosensory
 Provides information concerning relative position of body parts to support
surface & each other
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Somatosensation = Proprioceptive system
 Specialized variation of the sensory modality of touch,
encompassing joint sense (kinesthesia) & position
 Process
 Input from mechanoreceptors
 Stretch reflex triggers activation of muscles about a joint
because of perturbation
 Results in muscle response to compensate for
imbalance and postural sway
 Muscle spindles sense stretch in agonist, relay information
afferently to spinal cord
 Information is sent back to fire muscle to maintain postural
control
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Body position in relation to gravity is detected by sensory input
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Balance movements involve a number of joints
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Ankle
Knee
Hip
Coordinated movement along kinetic chain
Balance Disruption
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Balance Deficiencies - Inappropriate interaction among 3
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2 Factors that Disrupt Balance
sensory inputs
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Position of COG relative to base of support is not accurately
sensed
Automatic movements required to maintain the COG are
not timely/effective
Assessment of Balance
A comprehensive balance assessment is an integral
part of the initial evaluation and should be undertaken
when a balance deficit is suspected.
The balance assessment includes
(1) Subjective assessment
(2) Functional mobility and gait assessment
(3) Musculoskeletal evaluation
(4) Assessment of movement strategies and sensory
systems used for balance
Balance Equipment
Subjective Assessment
The subjective assessment gives a general overview of
nonobjective and nonmedical factors that contribute to loss of
function. This includes :
- medical history
-recent history of falls
-review of medications—especially those medications that
may contribute to loss of balance
FUNCTIONAL MOBILITY AND GAIT ASSESSMENT
The purpose of functional mobility and gait tests is to evaluate
how a person performs on functional tasks that depend on
postural control. A variety of objective and repeatable
functional tests are available, which provide a baseline for
documenting improvement. Functional tests can be divided
into two categories: functional mobility tests and functional gait
tests.
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Romberg Test – traditional assessment
Functional Mobility
A functional mobility assessment testing the ability to perform specific daily
tasks Functional mobility tests include the Berg Balance Test, the
Functional Reach Test, the Get Up and Go Test.
BERG BALANCE TEST
The Berg Balance Test is a widely-used test of functional mobility and
balance—especially with the ambulatory elderly. The Berg test is intended
to objectively evaluate a patient's ability to safely perform several common
daily living tasks and to assess fall risk, it includes:
-Sit to stand and stand to sit
-Unsupported sitting and standing
-Transfer from bed to chair
-Stand eyes closed
-Stand feet together
-Stand one foot in front of the other
-Functional reach test
-Retrieve an object from the floor
-Single-leg stance
-Look over shoulder
-Turn 360 degrees
-Alternate foot on stool
Functional Gait
Clinics developed a working protocol for assessing and
measuring functional gait. Is it functional to be able to walk
from the couch to the bathroom? How about the ability to
walk inside the house but not outside? Is functional gait
measured by distance, time, or energy expenditure? There is
much confusion and disagreement in the clinical setting
regarding even a basic definition of functional ambulation.
THE MUSCULOSKELETAL ASSESSMENT
The musculoskeletal portion of the balance evaluation
includes assessment of the following items:
-Strength
-Range of motion (ROM)
-Pain
-Posture
-Abnormal tone
MOVEMENT STRATEGIES FOR BALANCE
Is the way in which the nervous system accesses a motor
reaction in response to sensory input. Strategies are
automatic reactions, slower than reflexes but much faster
than voluntary movements. Three anterior-posterior
movement strategies have been identified: the ankle, hip
and stepping strategies
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Balance Training
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Aims
1.
2.
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Decrease the risk of injury
Can be incorporated as a preventative measure
Should be included in exercise programs for
Obese individuals, elderly, people with Lower Extremity injury
rehab, or for someone with a balance deficiency
Rules of Balance Training
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- Exercise must be safe & challenging
- Stress multiple planes of motion
- Incorporate a multisensory approach
- Begin with static, bilateral & stable surfaces & progress to
dynamic, unilateral & unstable surfaces
- Progress towards sports specific exercises
- Utilize open areas
- Assistive devices should be in arms reach early on
Classification of Balance Exercises
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Static
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Dynamic
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COG is maintained over a fixed base of support, on a stable surface
Maintenance of COG within LOS over a moving base of support while
on a stable surface (involve stepping strategy)
Functional
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Same as dynamic with inclusion of sports specific task
I. Static Balance Control
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- Having the patient maintain sitting, half-kneeling, tall kneeling, and
standing postures on a firm surface.
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- More challenging activities include practice in the tandem and single-leg
stance, lunge, and squat positions.
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- Progress these activities by working on soft surfaces (e.g., foam, sand,
grass), narrowing the base of support, moving the arms, or closing the
eyes.
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- Provide resistance via handheld weights or elastic resistance.
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- Add a secondary task (i.e., catching a ball or mental calculations) to
further increase the level of difficulty.
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Static balance training
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Bilateral to unilateral on both involved
& uninvolved sides
Utilize multiple surfaces to safely
challenge subject & maintaining
motivation
With & without arms/counterbalance
Eyes open & closed
Alterations in various sensory
information
II. Dynamic Balance Control
- Progress the activities by superimposing movements
such as shifting the body weight, rotating the
trunk, moving the head or arms.
- Vary the position of the arms from out to the side to
above the head.
Balance while standing on wobble
boards with arms above the head.
Balance while standing on wobble
boards with arm movements
- Practice stepping exercises starting with small steps, then mini-lunges, to full
lunges.
- Progress the exercise program to include hopping, skipping, rope jumping, and
hopping down from small stool while maintaining balance.
- Have the patient perform arm and leg exercises while standing with normal stance,
tandem stance, and single leg stance.
One-legged stance with resisted
shoulder extension using elastic
resistance.
-Reactive Balance Control
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Have the patient work to gradually increase the amount of sway
when standing in different directions while on a firm stable surface.
To emphasize training of the ankle strategy, have the patient
practice while standing on one leg with the trunk erect.
To emphasize training of the hip strategy, have the patient walk on
balance beams or lines drawn on the floor; perform tandem stance
and single-leg stance with trunk bending; stand on a minitrampoline, rocker balance, or sliding board.
To emphasize the stepping strategy, have the patient practice
stepping up onto a stool or stepping with legs crossed in front or
behind other leg (e.g., weaving or braiding).
To increase the challenge during these activities, add anticipated
and unanticipated external forces. For example, have the patient lift
boxes that are identical in appearance but of different weights;
throw and catch balls of different weights and sizes; or while on a
treadmill, suddenly stop/start the belt or increase/decrease the
speed.
Bilateral Stance Exercises
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Unilateral Semi-dynamic exercises
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Emphasize controlled hip flexion, smooth controlled motion
Single leg squats, step ups (sagittal or transverse plane)
Step-Up-And-Over activities
Introduction to Theraband kicks
Balance Beam
Balance Shoes
III. Functional Balance Activities
- The therapist should focus on activities similar to the
functional limitations identified in the evaluation. For
example, if reaching is limited, the patient should work on
activities such as reaching for a glass in a cupboard,
reaching behind (as putting arm in a sleeve), or catching a
ball off center.
- Having the patient perform two or more tasks simultaneously
increases the level of task complexity.
- Practicing recreational activities the patient enjoys, such as
golf, increases motivation for practice while challenging
balance control
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Functional types of exercise
Slow to fast, low to high force, controlled to uncontrolled
Start with bilateral jumping drills – straight plane jumping
patterns
Advance to diagonal jumping patterns
 Increase length and sequences of patterns
Progress to unilateral drills
 Pain & fatigue should not be much of a factor
Can also add a vertical component to the drills
Addition of implements
 Tubing, foam roll
Final step = functional activity with subconscious dynamic
control/balance
Functional Balance Activities