Balance

BALANCE

Postural orientation –The control of relative positions of the body parts by skeletal muscles with respect to gravity and each other. Postural stability :the condition in which all the forces acting on the body are balanced such that the center of mass (COM)is with in the stability limits or boundaries of BOS

DEFINITION Balance is the ability to maintain the equilibrium or It is the ability to maintain center of gravity (COG) over the base of support (BOS) Overall goal of balance control system to give Stability and function , achieved through integrated CNS system of control

Balance  Foundation of coordination  Center of gravity (COG) constantly shifts over base of support (BOS)  If sway exceeds limits of stability = compensation  If sway is within limits of stability = postural stability

Neuromuscular Synergies

Musculoskeletal Components

Body Schema

BALANCE Sensory Systems

Proactive Mechanisms (external)

Reactive Mechanisms

Anticipatory Mechanisms (internal)

postural stability  Ability to maintain the COG within stability limits.  Normal anterior/posterior sway – 12 degrees from most posterior-anterior position.  Lateral sway 16 degrees from side to side.  If sway exceeds boundaries, compensation is employed to regain balance. A smaller envelope is created and tolerated

Envelope of Sway

The maintenance of balance is based on an intrinsic cooperation between the  Vestibular system  proprioceptive,  tactile information  vision not only depends on the integrity of the systems but also on the sensory integration with in the CNS, visual and spatial perception, effective muscle strength and joint flexibility

Triad of balance • Somatosensory  Free nerve endings  Golgi ligament endings  Muscle spindles

Difference Visual

Vestibular

Provides sensory information Provides information regarding the position of the regarding orientation of the head in space and head relative to the acceleration. environment, and orients the head to maintain level gaze.

Response Strategies • Ankle Strategy

• Hip Strategy

 Used when displacements are small.  Displaces COG by rotation about the ankle joint.  E.g., Posterior displacement of COG – Dorsiflexion at ankle, contraction of anterior tibialis, quadriceps, abdominals.  Anterior COG displacement – Plantar flexion at ankle, contraction of gastrocnemius, hamstring, trunk extensors.

 Employed when ankle motion is limited, displacement is greater, when standing on unstable surface that disallows ankle strategy.  Preferred when perturbation is rapid and near limits of stability.  Post. Displacement COG – Backward sway, activation of hamstring and paraspinals.  Ant Displacement COG – Forward sway, activation of abdominal and quadricep muscles.

Stepping Strategy If displacement is large enough, a forward or backward step is used to regain postural control

• Hip Strategy  Employed when ankle motion is limited, displacement is greater, when standing on unstable surface that disallows ankle strategy.  Preferred when perturbation is rapid and near limits of stability.  Post. Displacement COG – Backward sway, activation of hamstring and paraspinals.  Ant Displacement COG – Forward sway, activation of abdominal and quadricep muscles.

Stepping Strategy  If displacement is large enough, a forward or backward step is used to regain postural control

In the normal individual, balance is maintained almost completely at a subconscious level. In retraining a patient’s balance ,the patient trained to react to stimuli rather than to make a conscious, voluntary effort to maintain equilibrium Balance, therefore, is the basis of all static or dynamic postures and should be considered when planning any exercise or rehabilitation programme

 Balance reaction can also be used to facilitate the contraction of selected muscle groups and as part of a muscle-strengthening programme  Static balance and dynamic balance  Treatment of balance impairment requires a detail examination to determine the system at fault.

Causes of balance impairment  Injury to or diseases of the structures (e.g. eyes, inner ear, peripheral receptors, spinal cord, cerebellum, basal ganglia, cerebrum)  Damage to Proprioceptors  Injury to or pathology of hip, knee, ankle, and back have been associated with increases postural sway and decreased balance  Lesions produced by tumor , CVA, or other insults that often produced visual field losses

Assessments of posture can Provide useful information about functional balance  Observe balance during quite standing  During movt from one posture to another  Assess the amount of help subject need to maintain the position  Apply pressure to the trunk in various direction ,encourage subjects to hold the position (or say don’t let me move you )  Test subject ‘Automatic reaction' to balance disturbance by moving them.

Clinical evaluation of balance Functional balance test Traditional Test for balance is Static balance Dynamic balance •Static balance - Double limb stance, Single limb stance, Tandem stance Romberg test Sharpened Romberg test. Standing in tandem position with eye open to eye closed

Dynamic balance – Standing Up Walking Turning Stopping Subjective grading Scales are Normal Good Fair Poor Absent

Absent Impaired present

Standardized tests and measures of balance Functional reach test Berg balance scale

Functional reach test : (Duncan et al.) Test of dynamic standing balance Def : The maximal distance one can reach forward beyond arm’s length while maintaining a fixed BOS in standing position.

Reference scale 20 to 40 yrs: 41 to 69yrs: 70to 87yrs :

14-17 inches 13 to 16 inches 10-13

Berg balance scale Test for both static and dynamic balance Scale consists of 14 functional task commonly performed in everyday life  Ranging from sitting to standing , standing to sitting. Variation in standing position ( Eyes closed, feet together,reaching forward, - Retrieving an object from the floor - Turning - Standing on one foot - Place foot on the stool.) Scoring by 5 point ordinal scale ranging from 0 to 4

The Performance –oriented mobility test by Tinetti et al Assessment for  position changes, response to perturbations and Gait movement during ADL `

Scales range fro 0-2

Get Up and Go (GUG) test by Mathias et al Measures basic mobility and balance Scored using 5-point ordinal scale with scores from 1 - Normal(no risk of falling) 2 -

Very slightly abnormal

3 -

Mildly abnormal

4 -

Moderately abnormal

5 -

Severely abnormal (high risk of falling)

Equilibrium reactions  Ensures body posture when a change occurs in supporting surface there are two components Place the subject supine or standing or on a tilting table., the initial observation is a stretching out of the extremities to the side which the tipping is occurring, accompanied by slight abduction . gradually , compensatory abduction of the leg and the arms to opposite side takes place .

ACTIVTIES FOR TREATING BALANCE IMPAIRMENT To determine the cause of the impairment Mode a variety of mode can be used to treat balance impairment  Begin with weight shifts on a stable

surface Gradually increase sway Increase surface challenges (mini-tramp, etc.) Any

cause of impairment such as Weakness Decreased mobility Pain should be treated first .

Rehabilitation balls ,foam rollers ,foam surfaces are often used to • Provide uneven or unstable surface for exercise • Sitting balance ,trunk stability, and weight distribution can be trained on a chair,table ,or therapeutic ball  Pool is an ideal palace for training balance

Posture Awareness of posture and the position of the body in space is fundamental to balance training Begin

in supine or seated position Over sessions, use a variety of arm positions, unstable surfaces, single leg stances, etc.

Mirrors can provide postural feedback –Visual feedback

Movement Training for both Static posture & Dynamic posture Environment -the environment for balance training depends on the Patient's situation For the frail elderly or those with significant balance impairment , most of the training activity takes place in clinic For athletes or other active individual with Musculoskeletal cause of balance impairment, balance activity can be carried at home

movt  Adding movement patterns to acquired stable static postures increases balance challenge.  Add ant./post. sway to increase stability limits.  Trunk rotations and altered head positions alter vestibular input.  PNF techniques during trunk rotation.  Stepping back/forward assists in restabilization exercises.

Sequence –Progression of exercise from simple to complex involves

BOS – Advance from wide to narrow base Posture – Stable to unstable posture (sway) Visual – Closing of the eyes COG – Greater disruption to elicit hip or stepping strategy Progress to more dynamic activities, unstable surfaces, and complex movement patterns Frequency,intensity,and duration – It of less issue

PRECAUTIONS

Patients safety A gait belt Parallel bars CONTRAINDICATION

Cognitive impairment

Patients education