Neurophysiology 6: Putting It Together (Lecture 80)

Question 1

What region is the Brachial Plexus in?

Answer 1

C6-T2

Question 2

What region is the lumbosacral plexus in?

Answer 2

L4-S3

Question 3

A lesion in the L4-S3 region. Would the signs in the pelvic limb be UMN or LMN?

How would the reflexes be impacted?

How would the muscle tone be impacted?

How would atrophy be impacted?

Answer 3

LMN damaged (LMN signs)

Reflexes decreased to absent.

Decreased muscle tone

Rapid atrophy

Question 4

Where would the lesion be if the dog is exhibiting LMN signs in the thoracic limbs?

Answer 4

Brachial Plexus

Question 5

If the lesion is in the brachial plexus, which neuon signs would be exhibited?

Answer 5

LMN Thoracic Limb
UMN Pelvic Limb

Question 6

What types of signs would we see in the thoracic limbs if the lesion were in C1-5? Pelvic limb?

Which one is worse? Why?

Answer 6

Thoracic: Upper Motor Neuron Sings
Pelvic: Upper Motor Neuron Signs

Pelvic would be worse because it has to do with the anatomy of the white matter. The ascending fibers of the pelvic limbs are more superficial

Question 7

What does cerebellar ataxia look like?

Answer 7

Toy solider walk in thoracic limbs

Crossing over and falling out behind