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
