Transcript Document
Balance and Falls
Nancy V. Karp, Ed.D., P.T.
Normal Postural Control
Postural control involves controlling the body’s position in space for:
Stability
Orientation
Falls
Falls in the elderly are a major cause of:
morbidity
Mortality
The underlying causes of falls is a complex interaction of:
Biomedical factors
Physiological factors
Psychosocial factors
Environmental factors
Incidence and Cost of Falls in the Elderly
Falls of people 65+
One third of people 65+ fall each year.
Elders > 75 account for 60% of fall-related deaths.
25% of elders who fracture their hip in a fall will die within a year.
Costs
Falls account for 70% of all injury-related costs for the elderly,
The average cost for a fall injury is $20,000.
Falls in the Elderly
Most falls result in minor or no injury.
Repeat fallers tend to fall in the same manner as they did in the previous fall.
A single fall results in:
Fear of falling and loss of confidence
Restriction in activities
Social isolation
Dependence on others
Identification of Fall Risk Factors
Risk factors for falls are divided into two categories:
Intrinsic Risk Factors Dizziness, weakness, gait abnormalities, poor balance, confusion, poor coordination, ROM, cognitive impairment
Extrinsic Risk Factors Floor surface, poor lighting, cluttered furniture, obstacles, non-level surface, poor shoes
Falls are a result of loss of postural control.
Normal Postural Control (Balance)
Balance requires keeping the “Center of Mass” (COM) over the “Base of Support” (BOS) during static and dynamic situations.
Neural components of postural control:
Sensory processes visual, vestibular, somatosensory
Central processing a higher-level integrative process
Effector component
sometimes referred to as the neuromuscular component
postural alignment, ROM, muscle force, power & endurance
Normal Postural Control
Adaptive postural control requires modifying sensory and motor systems to changing tasks and environmental demands.
Postural Control During Quiet Stance
Body aligned to minimize the effect of gravitational forces.
Muscle tone
Postural tone
Quiet Stance
Limits of Stability (LOS)
The maximum angle (from vertical) that can be tolerated.
How far you can shit from front to back and side to side without loosing balance? This is often called your “Cone of Stability.”
“Postural Sway” refers to small postural shifts from front to back and side to side, during quiet stance.
Limits of Stability
Cone of Stability
Cone of Stability with Assistive Device
Postural Sway
The larger the sway path, the greater the postural unsteadiness.
Romberg Test- Closing eyes will decrease visual input. “Standing Postural Sway” may increase, decreasing balance.
Postural Control During Perturbed Balance
The recovery of stability requires movement strategies that control the COM over the BOS.
“Limits of Stability” is defined as the distance a person can move, without losing balance or taking a step.
Perturbed Balance Movement Strategies
The “ankle strategy” occurs with minimal perturbance of balance.
Control is distal- to-proximal
Perturbed Balance Movement Strategies
Moderate instability leads to the “hip strategy”.
Control is proximal-to-distal
Perturbed Balance Movement Strategies
The “stepping strategy” is used with greater perturbance.
Perturbed Balance Central Nervous System
The response can either be protective or corrective.
“Anticipatory Postural Control” refers to postural adjustments that are made before voluntary movements to minimize disturbances in balance (feed forward).
Perturbed Balance Central Nervous System
“Reactive control” is the response to a disturbance in balance (feedback).
Corrective Strategy, such as the “ ankle strategy”
Protective Strategy, such as covering your head when you fall This does not correct the fall, but controls the effects of the fall.
Perturbed Balance Movement Strategies
The CNS activates muscle synergies in related joints.
Force in one part of the body does not cause instability in another part of the body.
Leaning over in a chair to pick up a pen, you do not fall out of the chair.
Neck extension during the “hip strategy” prevents the body from falling forward.
Central Processing Tests
Manual Test of Postural Perturbance
Therapist pulls patient, at waist level, several times with varying degrees of force.
See Guccione, p. 287
Normal Postural Control Sensory System
During perturbance of balance:
Adults rely on somatosensory inputs.
Children rely more on visual input.
The interaction of the senses allows the modification needed to maintain stability in a variety of environments.
Normal Postural Control Sensory System
The three different parts of the sensory system provide different sources of information about the body’s position and movement in space.
Each sense provides a different frame of reference for postural control.
Normal Postural Control Sensory System
The “Postural Dyscontrol” Test will be performed in class.
“Foam and Dome Test” O’Sullivan, p. 193
Normal Postural Control Sensory System
Vision provides information about the position and motion of the head in the environment.
Acuity- detects subtle differences in shapes Snellen Eye Chart (min 20/200)
Depth perception Finger Test, Guccione p. 286
Peripheral vision Finger Test, Guccione p. 286
Normal Postural Control Sensory System
T he somatosensory system provides information about the body with reference to supporting surfaces.
The somatosensory system receives information from muscle spindles, joint receptors, tendon organs, and mechanoreceptors.
T he Somatosensory system
Gross Tests of Proprioception
Detecting the subtle movement of the big toe (< 5mm).
Vibration- Placing a tuning fork at the first metatarsal head.
Normal Postural Control Sensory System
The Vestibular System
Provides information about the position and movement of the head, in reference to gravity and inertial forces.
Information is received from the vestibule responsible for position and linear acceleration.
Information is received from the semi-circular canal responsible for rotational movement.
The Vestibular System
Gross Functional Tests Guccione, p. 286
Looking at a object while turning head
Reading a book while walking
Marching in place with eyes closed
Postural Control
Controlling the body’s position in space is an essential part of functional skills.
Postural control requires all three:
Sensory system
Central processing
Effector components
Postural Control
The three systems in postural control are complex and multifaceted. A problem or impairment in one area may affect several other areas, resulting in a greater affect than the loss of the single impairment.
The Effect of Aging on Postural Control
The Sensory System
With aging, vision may decrease in acuity, contrast sensitivity, and depth perception
With aging, the vestibular system may undergo age-related changes, resulting in dizziness and unsteadiness.
With aging, there may be a decrease in proprioception and vibration.
Aging Effects on Postural Control
The Central Processing System
Aging may result in a slowing of sensory information.
Aging may result in a slowing of nerve conduction velocity.
Aging may result in increased postural sway.
Aging may result in an increased incidence of co contractions
Aging may result in an increased use of proximal to-distal control for balance.
Aging Effects on Postural Control
The Effector System
Aging may result in decreased muscle strength.
Aging may result in decreased ROM and flexibility.
Aging may result in increased “stiffness” of connective tissue
Aging may result in cardiovascular changes
Functional Tests
Progressive Mobility Skills Assessment Task
Guccione, p. 288 Berg Balance Scale (note that the “Functional Reach Test” is part of this test) O’Sullivan, p. 208
Performance-Oriented Assessment of Mobility I (Tinetti) O’Sullivan, p. 210
Other Assessments
Environmental Assessments Chapter 12, O’Sullivan
Psychosocial Assessment
Cognitive assessments
Social work assessments
Interventions
Interventions should be based on assessment results.
The ultimate goal will is to maximize independence in mobility and function.
The therapist needs to identify and treat modifiable deficits.
The therapist needs to identify and help the patient compensate for deficits that cannot be modified.
Some balance exercises for older people.
Exercises - National Institute on Agingl
Tandem Walking
Fall Prevention
The purpose of assessment and intervention is to prevent the next fall.
Balance and Falls
The End