W11: Coordination/Dexterity (Mental adroitness)

Question 1

What is coordination/dexterity?

Answer 1

Refers to the accuracy and precision of movement (ability to fractionate, to make independent movements).

For coordination you need to be able to contract the:
- right muscles
- right time
- right sequence
- right force

Question 2

What part of the brain controls this process?

Answer 2

The cerebellum

Question 3

What are the three subdivisions of the cerebellum?

Answer 3

Vestibulocerebellum
Pontocerebellum
Spinocerebellum

Question 4

Vestibulocerebellum: output and function

Answer 4

Output: vestibular nuclei
Function: Balance

Question 5

Pontocerebellum: output and function

Answer 5

Output: Primary motor cortex
Function: motor planning

Question 6

Spinocerebellum: Output and function

Answer 6

Output: Rubrospinal & Tectospinal
Function: muscle tone and posture

Question 7

Define dysmetria

Answer 7

Missing the target. The inability to control the distance, speed and ROM necessary to perform smooth coordinated movements. Hypometria – stop before the target or hypermetria – extend past the target.

**Scaling issue: inability to judge distance or scale

Question 8

Define akinesia (timing)

Answer 8

Reduced movement due to problems with planning/ loss of ability to move muscles voluntary (no motor planning to change in time eg they might see a pole and either walk into it or freeze in front.

Question 9

Define hypokinesia (timing)

Answer 9

Reduced movement range –> needs small movements.

Hypokinesia refers to a decrease in the amplitude or speed of voluntary movements. It is characterized by reduced movement.

Individuals with hypokinesia move more slowly and have smaller movements than normal. This can affect walking (shorter steps), facial expressions (less expressive), and other voluntary activities.

Question 10

Define synergies (Sequencing)

Answer 10

Coordinated movement eg picking up a bottle = shoulder, elbow flexion, wrist neutral, etc. Abnormal synergies = all or nothing, challenge with the muscles doing different things at the same time eg everything goes into flexion (common after a stroke or injury to corticospinal tract due to reduced coordination.

Question 11

Define co-activation (Sequencing)

Answer 11

Picking up water bottle, for elbow flexors to contract – need to lengthen. Antagonist can contract and not allow for the water bottle to be brought up.

Question 12

Define impaired inter-joint coordination (Sequencing)

Answer 12

Different movements at different joints –> this allows us to do alternated movements eg while walking one needs to extend and one flexes and that happens continuously (this is called dysdiadochokinesia – different coordinated movements at a certain speed).

Question 13

Define ataxia

Answer 13

Reduced coordination and timing problems (difficulties in initiating the movement eg dropping a ball)

Question 14

Coactivation issue: agonist and antagonist muscles during functional movement. Provide an example…

Answer 14

Cerebral Palsy

Question 15

Impaired inter-joint coordination involves what….
Examples include….

Answer 15

Ataxia & dysdiadochokinesia

Example: Cerebellar pathology, parkinsons, stroke & hemiparesis

Question 16

What falls under sequencing, timing and scaling issues?

Answer 16

Sequencing
* Abnormal synergies
* Coactivation
* Interjoint coordination
* Dysdiadochokinesia

Timing
* Bradykinesia, hypokinesia and akinesia

Scaling
* Dysmetria

Question 17

How do we assess coordination?

Answer 17

• Finger-to-finger / finger-to-nose tests
• Heel-to-shin test
• Forearm supination / pronation test
• Rebound test

Note: THE ASSESSMENT IS LOOKING AT THE QUALITY OF THE MOVEMENT & THE ACCURACY. ASSESS WITH EYES CLOSED BECAUSE WITH EYES OPEN THEY CAN USE VISION TO ASSIST IN COORDINATION. EYES CLOSED MAKES THEM RELY MORE ON PROPRIOCEPTION.

Question 18

What is the compensatory treatment approach?

Answer 18

• Rx at levels of activity limitation and participation restriction eg my patient cannot walk because they have paralysis of the lower limbs –> get a wheel chair and teach them how to move differently (not actually treating the problem)
• Involve the provision of external cues and equipment to help patient achieve task

Question 19

What is the restorative treatment approach?

Answer 19

• Rx at level of impairment –> treat the problem eg if the muscle is weak we are going to strengthen, if the muscle is short we are going to lengthen, etc. Induce the neuro system to tap into neuroplastic mechanisms of the CNS.
• Involve techniques to improve recovery of the central nervous system