Coordination and Balance Exam Flashcards
1
Q
Motor systems involved in coordination/balance
A
- Peripheral systems: muscles and joints
- Central systems: 3 levels (flexible hierarchy), Strategy level = decides the goal of movement, represented by association motor areas, basal ganglia, & cerebellum; Tactics level = decides sequence of muscle contraction in space & time, represented by primary motor cortex & cerebellum; Execution level = stimulate motor neurons to activate muscles appropriately for movements/postural control, & feedback (cerebellum)
2
Q
Coordination impairments associated with cerebellum
A
- Ataxia: most common problem, results in ‘ataxic gait’ (poor trunk control, wide BOS, arms high guard position, irregular stepping)
- Dysdiadochokinesia: impaired ability to perform RAM (rapid alternating movements)
- Dysmetria: inability to judge the distance, over-/under- shooting
- Dyssynergia: inability to perform smooth movements using synergistic muscle
- Nystagmus: mostly vertical nystagmus
- Tremor: intention tremor, during movements, tends to increase with speed
- Dysarthria: scanning speech, hanging onto syllables for too long/pronounced
3
Q
Coordination impairments associated with basal ganglia
A
- Bradykinesia: slow movements, decreased arm movements, shuffling, & destination during gait (Parkinson’s gait)
- Akinesia: progression to inability to initiate movements (freezing gait)
- Athetosis: involuntary writhing/’worm-like’ movements (clinical sign of athetoid cerebral palsy)
- Chorea: involuntary irregular jerky movements, cannot be inhibited, mostly seen in UE (clinical sign of Huntington’s disease)
- Dystonia: sustained involuntary contractions of agonist/antagonist muscle, abnormal posturing, torsion spasms
- Rigidity: lead-pipe & cog-wheel types
- Tremor: resting tremor (pill-rolling in fingers in Parkinson’s disease)
- Hemiballismus: large amplitude movements, sometimes violent, one side of body, arm or leg
4
Q
Sensory impairments involved in coordination/balance
A
- appropriate sensory input is also critical for coordination & balance
- responsible for joint position sense, kinesthesia, discriminative touch
- Romberg’s sign tests for imbalance/incoordination due to proprioceptive loss, also sharpened Romberg
5
Q
Coordination tests
A
- Gross vs Fine motor tests
- Gross motor tests: involve large muscle groups to test ability to crawl, kneel, stand, walk w/o abnormal postures w/o loss of balance, called equilibrium tests
- Fine motor tests: involve small distal muscle groups, test fine motor activities like finger dexterity tasks, non-equilibrium tests
6
Q
Fine motor/non-equilibrium tests
A
- finger to nose
- finger to examiner’s finger
- finger opposition
- rapid alternating pronation/supination (diadochokinesis)
- rebound test
- tapping hand/foot following rhythm
- pronator drift test with eyes closed: either contralateral pyramidal lesion or ipsilateral cerebellar or DC/ML lesion, also tests proprioceptive loss
- alternate heel to knee, heel to toe
- heel on shin
- drawing circle/figure of 8: both UE and LE
- use some kind of rating scale: time to completion, error rates
7
Q
Standardized instruments for UE coordination
A
- mostly measure time for completion & accuracy
- 9 hole peg test
- Jebsen Taylor hand function test: writing, card turning, stacking
- Minnesota Manual Dexterity test: used to select personnel for work requiring coordinated hand/finger movements
- O’connor Tweezer test
- Computerized instruments for assessment: ARMEO
8
Q
What is the dynamic systems theory
A
- postural control movements are also guided by the task at hand, our individual capabilities, & the environmental constraints
9
Q
Define balance/postural control
A
- condition in which all forces acting on body are balanced such that the center of mass (COM) is within base of support (BOS)
- also called postural control
10
Q
Define COM
A
- center point of the whole body mass
- same as center of gravity (COG)
- occurs at 2nd sacral vertebra in anatomical standing
11
Q
Define line of gravity (LOG)
A
- vertical line from COM to floor
- expected to fall anterior to ankle and knee, posterior to hip joints, anterior to thoracic vertebrae, just anterior to shoulder joint, but can change with dynamic
12
Q
Define limits of stability (LOS)
A
- max distance one can lean/reach w/o taking step w/o loss of balance (LOB)
- also called the cone of stability
13
Q
Define postural alignment
A
- perfect alignment when line of gravity (LOG) passes through structures as expected
- minimal muscle activity required
14
Q
Define steadiness/postural sway
A
- ability to maintain COM/LOG at place with minimal movements
- can be measured by COP (center of pressure) movements on force plates
- normally exhibit small postural sway during standing
- sway envelope: path of excursion of the COP during quite standing
15
Q
Reactive balance strategies
A
- ankle
- hip
- suspension
- stepping
- reaching strategies
16
Q
Define fixed support strategies
A
- used to control COM over fixed BOS, COM remains within limits of stability so BOS does not change
17
Q
Describe ankle strategy
A
- move COM of body as a block about ankle joints
- used when sways are small/slow
- muscles are activated distal-to-proximal
- during forward sway, gastrocnemius -> hamstrings -> paraspinals
- during backward sway, tib ant -> quads -> abdominals
- used on firm support surface
18
Q
Describe hip strategy
A
- moves COM by flexing/extending/abd/adducting hips
- used with larger/faster sways
- muscles are activated proximal to distal
- forward sway, abdominals -> quads
- backward sway, paraspinals -> hamstrings
- used when support surface is small/narrow/complaint
19
Q
Describe suspension strategy
A
- moves COM down by flexing hips/knees & flexing trunk
- may progress to squatting
20
Q
Define change in support strategies
A
- used to control COM over moving BOS, such that the COM moves out of LOS
21
Q
Describe stepping strategy
A
- brings COM back within LOS by taking a rapid step in the direction of the destabilizing force
- recruited in response to fast large perturbations when ankle/hip strategies are not adequate to recover postural control
- should not viewed as strategy of last resort, they are recruited quickly ahead of ankle/hip strategies if CNS perceives a big perturbation
22
Q
Describe reaching/grasping strategies
A
- bring COM within LOS (limits of stability) by extending BOS by reaching/grasping using UE
23
Q
Describe protective reactions for reactive balance (and anticipatory balance) control in sitting
A
- use of trunk, head, arm, & leg responses during reactive or anticipatory balance control with increasing COG displacements
24
Q
Sensory systems involved in balance
A
- visual
- somatosensory
- vestibular
- provide important info about body’s own actions & surrounding environment
- the CNS then has to process/interpret those inputs & decide on goal-directed conscious response or unconscious adjustments to posture
25
Describe the visual system
- has roles in both feedforward & feedback balance mechanisms
- Feedforward balance: focal vision (central vision), to see obstacle ahead of you & react beforehand, needed for proactive/anticipatory postural control
- Feedbackward balance: ambient vision (mostly peripheral vision), to regain postural control after perturbations, needed for reactive postural control
26
Describe the somatosensory system
- provides cutaneous & pressure sensations form body segments in contact with support surface
- also proprioceptive sensations from muscles, tendons, & joints
- provide info about orientation & movement of body in relation to support surface
27
Describe the vestibular system
- provide CNS with info about position/movement of head with respect to gravity/inertial forces: provides 'gravitoinertial frame of reference'
- info about angular/linear acceleration
- functions to stabilize gaze during head movements using VOR also functions to regulate tone in postural/antigravity muscle for postural control using VSR
- it alone cannot provide true picture of body movements in space
28
How does the CNS integrate all 3 sensory inputs for 'best' balance performance
- it re-weighs sensory inputs, depending on the sensory environment & accuracy of the sensory info, shown by SOT (sensory organization test)
29
What are the 6 levels of balance tests for the sensory organization test
1) stable ground
2) stable ground with blind fold
3) stable ground with altered vision/visual environment
4) unstable ground
5) unstable ground with blind fold
6) unstable ground with altered vision/visual environment
30
Describe the modified clinical test for sensory integration of balance (mCTSIB)
1) stable ground
2) stable ground with blind fold
3) unstable ground
4) unstable ground with blind fold
31
Describe steady state balance
- quite sitting/standing
- ability to control the location of the body's center of mass within the area defined by the base of support under predictable quasi-static conditions
32
Describe proactive/anticipatory balance
- ability to generate postural adjustments prior to the onset of & during voluntary movement for the purpose of either countering an upcoming postural disturbance due to voluntary movement or realigning the body's COM prior to changing the BAS
33
Describe reactive balance
- ability to respond to sensory input that signals a need for a response to ensure successful maintain of postural control
- the need for a response is unanticipated but may be generated externally or secondarily to an internally generated movement
34
10 balance dysfunction diagnoses
- Postural moment strategies: primarily related to abnormal postural movement strategies (steady state postural control/SSPC, anticipatory postural control/APC, & reactive postural control/RPC)
- Sensory processing: primarily related to abnormal sensory integrity/processing (SSPC, APC, and RPC)
- Balance confidence: primarily related to fear of falling/reduced self-efficacy (SSPC and APC)
- Verticality: primarily related to impaired orientation with respect to gravity (SSPC)
- Executive function/multitask ability: primarily related to impaired dual-task ability (APC)
35
Examples of steady state balance tests
- single limb stance time test
- Romberg test
- CTSIB (mCTSIB)
36
Examples of anticipatory balance tests
- Functional Reach Test
- Multi-Directional Reach Test
- Star Excursion Balance Test/YBT (Y-Balance Test): test of LE reach that challenges an individual's limits of stability
37
Examples of reactive balance tests
- Retropulsive Pull Test
- Push and Release Test: better test, 0 = recovers w/1 step; 1 = 2-3 small steps, independently recovers; 2 = ≥4 steps, independent recovery; 3 = multiple steps, needs assistance to prevent fall; 4 = falls w/o attempting steps
38
Tests for seated balance
- FIST (function in sitting test): tests mostly anticipatory balance
- SATCo (segmental assessment of trunk control)
39
Tests for standing balance
- FRT (functional reach test)/MDRT (multi-directional reach test): MS (cut off for normal <7 inches)
- Romberg (NBOS)/Sharpened Romberg (tandem stance)
- SLST
- 4-stage balance test
- DGI: MS
- FGA (functional gait assessment): core measure, PD
- Four square step test: MS
- BESS: steady state, mTBI/concussion
- Community mobility and balance scale: TBI (dramatic brain injury)
40
Combined sitting and standing tests
- TUG: SCI (spinal cord injury), cut off for normal is about 13 secs
- TUG cog, TUG man: MS, PD (Parkinson's disease)
- PASS: steady state vs dynamic, stroke
- BBS (cut off for normal <45): core measure, MS, SCI (spinal cord injury)
- (mini)BESTest: reactive vs anticipatory, stroke, PD (Parkinson's disease)
- 5-times sit-to-stand (can also be considered as a balance assessment): core measure for all neuro conditions, can also use 30-sec-chair-stand-test
41
Describe the cut offs for fall risk for the BESTest and the miniBESTest
- BESTest: <69% for general population or for Parkinson's disease
- MiniBESTest: <23/28 for fall risk
42
Describe the FGA standing balance test
- gait level surface
- change in gait speed
- gait with horizontal head turns
- gait with vertical head turned
- gait and pivot turn
- step over obstacle
- gait with narrow base of support
- gait with eyes closed
- ambulating backwards
- steps
43
Example interventions based on steady state postural control (SSPC) diagnoses
- Postural Movement Strategies: mirror with line for vertical & sitting or standing with visual, verbal, and/or manual cues
- Sensory Processing: standing feet together with eyes closed and tandem stance on foam
- Verticality: standing with back and heels against wall
- Balance Confidence: systematically reducing UE support or altering LE base of support in sitting/standing for longer periods of time
44
Example interventions based on anticipatory postural control (APC)
- Postural Movement Strategies: add UE & LE movement to functional tasks and stepping over obstacles
- Sensory Processing: marching with eyes closed and reaching with varying speed, direction, & amplitude
- Balance Confidence: systematically reducing UE support or increasing postural control challenge to allow successful task performance while incorporating self-efficacy strategies
- Executive Function/Multi-task Ability: increase challenge of balance task and increase difficulty of secondary task
45
Example interventions based on reactive postural control (RPC)
- Postural Movement Strategies: external perturbations and treadmill slip training
- Sensory Processing: marching with eyes closed and tandem standing with head turns
