Voluntary Movement- Corticospinal tract

Question 1

What is the role of corticospinal tract in movement

Answer 1

Sensory Input–> vestibular inputs, kinaesthesia, vision
Motor systems–> primary motor pathways, basal ganglia, cerebellum
Other relevant systems–> PROM and joint health, strength, cardioresp function

Question 2

Describe voluntary movement

Answer 2

automatic, fast, controlled and coordinated/accurate

Question 3

Define resting muscle tone

Answer 3

the underlying level of stiffness in the muscle

Question 4

define postural tone

Answer 4

what is holding you up at this time–> baseline level of muscle activity

Question 5

Define voluntary movement

Answer 5

Movement from a thought

Question 6

Define automatic movement

Answer 6

Subconscious movement

Question 7

Define negative effects of UMN/LMN

Answer 7

Loss of what existed

Question 8

Define positive effects of UMN/LMN

Answer 8

new features

Question 9

What are negative features of UMN syndrome

Answer 9

PRODUCING MOVEMENT

• Loss of dexterity (fractionated/voluntary movement/motor control)
• Weakness
• Fatigue

Question 10

What are positive features of UMN syndrome

Answer 10

REGULATING MUSCLE TONE

• Spasticity
• clonus
• Exxagerated DTR’s
• Associated movements
• Spastic dystonia
• Spastic co-contraction
• Spastic hypertonia
• Spasms

Question 11

What is spasticity

Answer 11

motor disorder characteristed by a velocity-dependent increase in tonic stretch reflexes (muscle tone)
-resulting from hyperexcitability of stretch reflexes

Question 12

What is rigidity

Answer 12

resistance to passive movement that is not velocity dependent

Question 13

What is loss of fractionated movement

Answer 13

Loss of ability to stabilise one body segment and move the adjacent body segments with control and purpose
-loss of ability to control stabilisation and movement at multiple joints for purpose of skilled movements

Question 14

Explain how the positive features of UMN syndrome occur

Answer 14

• Descending influences from cortex modulate spinal reflexes
• Lesion to COrticospinal system= loss of descending influences
• Initially spinal/cerebral shock= hypotonia (hence diminished reflexes in early stages of UMN as well)
• Chronic lack of modulation on spinal reflexes= hyperreflexia/spasticity

Question 15

How do you do a formal assessment of tone

Answer 15

Observation of posture

• palpation of muscle tension
• resistance to rapid passive movt.–> velocity dependent (difference b/q fast and slow)
• Tendon reflexes and babinski

Question 16

How does spasticity present

Answer 16

• Resistance to stretch–> velocity dependent
• Clonus= rapid stretch at end of range
• Clasp-knife phenomenon= muscle contracting rather than relaxing when lengthening it
• Hyperreflexia

Question 17

Describe a severe presentation of loss of fractionated movement

Answer 17

• Minimal ability to produce movement at all (movt. at all, through range and in opposite direction)
• Moderate severity of loss of fractionation= influence of abnormal movement synergists

Question 18

What are normal movement synergies

Answer 18

muscles contract in couples to produce degrees of freedom of movement

Question 19

What are abnoral movement synergies from UMN

Answer 19

Stereotyped movements that dominate voluntary movement after upper motor neuron lesion
Only certain way that the movt. can occur, not variable, hence stereotyped

Question 20

What are secondary impairments of UMN syndrome

Answer 20

(separate impairment, not a compulsory part of UMN)

• Contracture
• Loss of PROM
• Secondary to constant positioning in shorted range–> not a compulsory outcome