Corticospinal Tract and Motor Pathways Flashcards Preview

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Flashcards in Corticospinal Tract and Motor Pathways Deck (28):
1

Spasticity

Hyperrfexia

2

Signs of lower motor neuron lesion

Muscle weakness, atrophy, fasciculations, decreased tone, hyporeflexia

3

Fasciculations

Abnormal muscle twitch (e.g., eye twitch when tired or too much caffine)

4

Atrophy

Muscles waste away due to lack of use

5

What are upper motor neurons

Corticospinal tract where project from the cerebral cortex to lower neurons of the anterior horn

6

Lower motor neurons

In spinal cord and project via peripheral nerves to skeletal muscles

Also in the brainstem

7

Thoracic cord lesion sign

Dialated eyes

8

Significant sign of ALS

Both UMN and LMN signs

9

What areas does the motor feedback loop involve

Cortex, brainstem, cerebellum, basal ganglia, and thalamus

10

Lateral corticospinal Tract

Deliberate movement
Movement of contralateral limbs
Primary motor cortex, frontal, parietal

11

Medial motor systems

Trunk posture

12

How does motor input travel

Precentral region to internal capsule to lateral corticospinal tract

13

How does corricospinal tract travel?

Anterior media
Then jumps to lateral in the spinal cord

14

Pyramidal decussation

Where tract fibers cross over

15

Lesions above pyramidal decussation vs. lesion below

Above - contralateral weakness
Below - ipsilateral weakness

16

Unilateral face, arm, leg weakness cause - with no sensory deficit

Unlikely to be cortical because would involve the entire motor strip

Not spinal because face would be spared

Lacunar infarct or problem in the corona radiata

Above pyramidal deccusation

17

Signs of upper motor neuron lesions

Muscle weakness and a combination of increased tone and hyperflexia sometimes referred to as spasticity

Abnormal reflexes such as Babinski sign and Hoffman's sign

18

Unilateral face, arm, leg weakness cause - with somatosensory, oculomotor, visual, or higher cortical deficits

Could be infarct, hemorrhage, tumor, herniation, post-ictal state

Entire primary motor cortex

19

Somatosensory

Sensitive to touch

20

Paresis

Weakness (partial paralysis)

21

Plegia

No movement

22

Paralysis

No movement

23

Palsy

Weakness or no movement

24

Quadri- or tetra-

All four limbs

25

Hemi-

One side of the body

26

Para

Both legs involved

27

Mono-

One limb

28

Di-

Both sides of body equally affected