What exactly is balance?

Macpherson et al. (1997) contend that the maintenance of posture is the co-requisite for all coordinated movement,

and when studying the restoration of motor function after injury or disease,

it is essential to consider not only the specific motor task, but to also consider the postural control that is an integral part of that task.

Sensorimotor systems underlying postural control provide us with the ability to balance all the forces acting on the body, resulting in the ability to:

(Horak & Macpherson, 1996)

1) keep the body in a desired position - Static Equilibrium, or

2) move the body in a controlled way - Dynamic Equilibrium.

Systems Theory leading to aTask-Oriented Clinical Approach

Individual Task“a skilled action”

Environment

“characteristics of the performer”

“configured to fit the environment”

Balance

INDIVIDUAL

ENVIRONMENT TASK

1) Static Equilibrium

INDIVIDUAL

ENVIRONMENT TASK

2) Dynamic Equilibrium

INDIVIDUAL

ENVIRONMENT TASK

BALANCE

Anticipatory Mechanisms

(internal)

Proactive Mechanisms

(external)

ReactiveMechanisms

Sensory Systems

Body Schema

Neuro-muscular Synergies

Musculo-skeletal

Components

Sensory Systems

• Visual – PROACTIVE control

• Vestibular – Body Schema

• Somatosensory – REACTIVE control

Musculoskeletal Components

• Flexibility• Strength• Power• Endurance• Bone density• Posture

Reactive Mechanisms

Sensorimotor Strategies

Neuromuscular Synergies

Proactive Mechanisms

Anticipatory Mechanisms

What are these tests . . .testing?

• Functional Reach Test

• Berg Balance Test

• Sensory Organization Test

• Timed Up and Go Test

• Dynamic Gait Index

• Romberg

Constraints Model