Balance Flashcards
Define balance
The static or dynamic equilibrium of the body, relative to the support base:
Balance is maintained as long as the COG remains over the BoS
Balance is not based on a fixed set of equilibrium reflexes but on a flexible, functional motor skill that can adapt with training and experience
What is needed for balance
Sensory input:
- Proprioception
- Vestibular
- Visual
Central Processing:
- Sensory input into sensory cortex
- Motor initiation (basal ganglia) to motor output (motor cortex)
- Cerebellar co-ordination
Motor output:
- Muscle length, strength, power, endurance, tone
- Joint ROM
Balance reactions:
Saving and protective reactions:
- Visual fixing
- Lowering COG (requires muscle control)
- Stepping reactions
- Ankle and hip strategies*
- Head and trunk RR*
Feedforward mechanisms:
- Storage of learnt movement patterns in basal ganglia
- Anticipatory movement
Feedback mechanisms:
- Continuous sensory feedback
Where does sensory input comes from
- Vestibular system
- Vision
- Proprioception
What needs to remain intact for balance to be maintained
- Intact sensory receptors
- Intact PNS and CNS to transmit, receive and process sensory information
- Intact CNS and PNS to initiate, transmit and produce motor output
- Intact musculoskeletal system to produce movement
State type and function of the sensory receptors
Exteroceptive:
External environment: pain, touch, temp, vision (cones, rods in eyes)
- Free nerve endings - pain, touch, temp
- Merkel discs - touch
- Krause end bulb (in skin) - touch
- Root hair plexus - touch
- Meisner corpuscles (close to epidermis) - light touch
- Pacinian corpuscles (deeper in skin) - pressure, deep touch
- Ruffini endings (deep in skin) - pressure, deep touch
Proprioceptive:
Body position: from muscle, tendon, joint capsule
Muscle spindle, golgi tendons, joint receptors picking up info from stretching in muscles, muscle tension, joint movement & position
Interoceptive:
internal pain, unconscious sensation, from deep structures, vestibular
What is needed for sensory information to be transmittedted, received and processed
Intact sensory pathways:
- Dorsal columns – gracilis and cuneatus – touch, position and vibration
- Spinothalamic – pain and temp
- Spinocerebellar - proprioception
Intact sensory central processing:
- Sensory information to sensory cortex in Parietal lobe
- Sensory cortex perceives different parts of the body in different place – sensory homunculus
What is needed to initiate, transmit and produce motor output
Intact motor central processing:
- Motor cortex in the back of the frontal lobe links with the basal ganglia to produce movement
- Different areas of the cortex will stimulate different areas in the body - motor homunculus
Intact motor pathways:
- Corticospinal - Lateral – motor info for limbs, anterior – motor info for axial muscles
- Vestibulospinal - Integration of head and neck and trunk with extremities
- Reticulospinal - Lateral – facilitates flexion and inhibits extension. Medial – opposite
- Rubrospinal - Control of fine movement
- Tectospinal - Controls muscles in response to visual stimuli
The cyclical process of balance is co-ordinated mainly in which part of the brain
Cerebellum
What is needed to produce movement
Intact peripheral motor systems:
- Alpha motor neurone
- Muscle strength/length/power/endurance/tone
- Joint range
What is the structure & function of the vestibular system
Structure:
- Located in the inner ear; deeper than hearing mechanisms
- Made up of three semi-circular canals and otoliths
- Semi-circular canals pick up rotation, nodding, side flexion
- Fluid in semi-circular canals move and stimulate hairs that send info along vestibular nerves into brain
Function:
- Vestibular pathways - Vestibular afferents synapse on the vestibular nuclei in medulla and pons (brainstem) and send info to cerebellum
- Provides information to brain about movement and position of head
Name the automatic balance reactions you may see?
Ankle strategy
Move somebody challenge their balance
Looking for DF to pull pt forwards when pushed back
Looking for PF to pull backwards when pushed forwards
Hip strategy
Same as ankle but larger movements
Looking for hip reaction to keep CoG over BoS
Head and trunk righting reactions
Learned as a child and it becomes automatic with aging;
Lost in brain damage thus re-education required
Protective and saving reactions
Visual fixing on something
Lowering COG (requires muscle control)
Stepping reactions
Step done when CoG moves out of BoS
No reactions
State balance mechanisms
- Reactive - feedback return to stability after perturbation and in response to displacement; compensatory
- Proactive - feedforward and anticipatory learned response in response to expected displacement
How to assess for sensory input impairments
- Vestibular - Rapid movement tests
- Vision - Visual field
- Proprioception - Mirroring/joint position sense
- Somatosensory - Light and deep touch, sharp and blunt
How to assess for central processing impairments
Tone (high or low):
- AROM & PROM
- Damage to either alpha-motor neurone, descending pathways, motor cortex
Initiation of movement:
- AROM & function
- Damage to basal ganglia
Coordination:
- FTN/HTS and function
- Damage to cerebellum
Smooth movement:
- FTN/HTS and function
- Damage to cerebellum, descending pathways
Reactive:
- Function
How to assess for motor output impairments
- Tone - PROM/reflexes
- Muscle strength - Isometric or isotonic or AROM
- Joint ROM - AROM/PROM
What can you do in clinical practice to challenge balance?
- Reduce BoS – narrow stance, step stance, tandem stance, one foot
- Increase CoG – lying, sitting, perched sitting, standing
- Take away senses
- Encourage automatic reactions – balloon tapping, rolling, throwing & catching
- Add reactive or proactive elements
- Add dual tasking – functional activities, cognitive tasks
Standing balance treatment ideas
Individual - Step stand
Task - Standing/standing and throwing ball/heel lifts/onto toes/kick a ball, trap a ball/standing with a push
Environment - Standing on stable/unstable surface
Individual - Feet together forwards, backwards, sideways
Task - Standing with one foot on step
Environment - Use of parallel bars
Individual - Feet apart
Task - Sit to stand/stand to sit/squats/picking object up off the floor
Environment - High plinth, low plinth or perched sitting– sit to stand
Individual - Tandem stand
Task - Stepping with unaffected leg – forwards, backwards, sideways, step
Environment - Use gym ball, step - Sit to stand
Individual - Eyes open/closed
Task - Stepping with affected leg – forwards, backwards, sideways, step
Environment - Use of step, rollerskate, cloth
Individual - Talking
Task - Sliding foot with cloth/rollerskate
Environment - Use of table – front/side
Individual - Use of arms
Task - Standing and reaching – forwards/sideways/back
Environment - Use of ball, balloon, cones, functional objects
Outcome Measures for balance
- TUSS (Time unsupported steady standing/sitting) < 1 min at risk of fall
- Rombergs Test
- FR (Functional reach) <6” at risk of falls
- 180 turn <7 secs or >5 steps at risk of fall
- POMA (Performance Oriented Mobility Assessment or Tinetti) < 19 at risk of fall
- BBS (Berg Balance Scale) <45 = risk of fall
- GUAG (Get Up And Go)
- Four square step test
- Five times Sit to stand
- Alternate step test
- Star Excursion test (outpatient)
- Y balance test (outpatient)
Balance Rehab ideas in lying
- Holding crook lying; controlled knee rolling and return to midline
- Bridging, asymmetrical bridging, one legged bridging
Balance Rehab ideas for trunk alignment
Trunk alignment:
- Sitting behind patient to increase BOS
- Hands on either side of trunk – move from side to side, alternate elongation of either side
- Progress into flexion (focus on lat dorsi stretch (flexion / rotation)
- Once patient is symmetrical, facilitate sitting up straight / dropping back.
- Progress to touch my hand (with good hand - and affected hand on lap)
- Show tapping beach ball balloon to keep ‘fixing arm’ active
Weight-bearing in sitting:
- Touch my hand
- Sitting up straight, crossing good leg over bad leg
Aims of standing
- Increase proximal stability
- Increase extensor activity (in general and on affected side)
- Stimulation of balance reactions
Methods to facilitate standing
- Symmetrically sitting on edge of high plinth. Gradually bring patient into standing, blocking their affected knee and encouraging equal weight bearing.
- As above but with unaffected foot 1-2” in front of affected foot to increase weight bearing on affected limb
Standing balance progression rehab ideas
- Facilitate balance reactions (perturb – realign) include tapping & ‘don’t let me move you’.
- Perched sitting – stand (handling to facilitate affected side) – symmetrical and asymmetrical (to hemi side)
- Progress to lower sitting – stand (in midline and to affected side)
- Transfer weight onto affected limb (handling: facilitation not forcing)
- Stimulation of balance reactions (facilitation of extension / abduction of weight bearing hip)
- Standing to perched sitting
- Perched sitting to standing
- Standing to sitting to one side
- Standing, turn and lower one side of bottom to plinth
- Perched sitting, to standing over affected leg
- Symmetrical standing: gentle flex / ext good knee (stops fixing)
- Heel lifts (good leg)
- Progress to side step with good leg
- Progress to fwd / back steps
- Stepping on / off block
- Unaffected leg on cloth (polishing floor)
- Unaffected foot on roller skate
- Unaffected foot on block: slow, controlled squats with affected leg
- Simultaneous activities in upper limb to promote proximal stability
