Neurology start on 9/8 Flashcards
What might be the signs that you’d see if an animal had this condition?
Nerve root signs
Hyperalgesia
monoparesis/plegia
LMN signs
What are the 3 common nerve injuries seen in peripheral nerve damage
neuropraxia
axonotmesis
neurotmesis
What is this type of nerve damage called
Neuropraxia
the nerve has been subject to decr blood supply, creates a feeling on numbness, no permanent damage if not too long of a duration.
A real problem in LA (when recumbent during sx or injury)
What type of nerve injury is this called
Axonotmesis
the axon is cut/damaged but CT/Schwann cells are still intact so regeneration can happen.
axon regeneration rate can be 1-4 mm/day
What type of nerve injury is this
Neurotmesis
total nerve damage, no regeneration
What is wrong with this kitty?
Ddx?
Paw not able to extend, elbow dropped
Radial n damage/paralysis
If you see these cats what do you think is wrong
Peripheral n damage
Cats have plantigrade stance
Sciatic nv damage
Seen commonly in diabetic cats
This pup was brought to your clinic. How do you figure out what is wrong. What CS might support your ddx?
How would you tx?
Hx of trauma
LMN signs: hypo/areflexia, hypo/atonia, neurogenic atrophy, hypasthesia
Glucocorticoid to decr inflammation
Decompress/protect from self/ physical therapy
arthrodesis/amputate 6 mos
What type of n injury is more common than peripheral n damage
Brachial plexus avulsion
How does brachial plexus avulsion happen
Trauma that abduct leg caudally/cranially
avulsion of nerve roots (C6-T2)
Which brachial plexus nerves affect will show signs in which part of forelimb
C6+C7 : extensors/flexors of shoulder
C8+T1 : extensors/flexors of elbow/carpus
C8 & T1 can affect Lateral thoracic n which will give decr panniculus reflex
T1 ventral n roots affect preganglionic sympathetic n give Horners syndrome!
This dog got hit by car 1 week ago. What is a possible dx? What CS support that?
brachial plexus avulsion
dropped elbow, radial n damage, neurogenic atrophy of shoulder mm.
What is the general tx for peripheral n damage or brachial plexus avulsion? Px?
Protect limb from injury/self trauma
physical therapy to maintain joint flexibility, vascular tone & stimulate neuronal connections
Give 6 months time then possibly amputate
pain predicts recovery
Generally poor px (30% recover)
This dog comes in and the owner says he thinks that shes been dragging the left rear leg more and more. You examine her and detect atrophy, “root sign” (hyperpathia) with limb palpation & manipulation.
What should be at the top of your Ddx list?
Nerve root/peripheral nerve neoplasia
MPNST (malignant peripheral nerve sheath tumor)
With MPNST’s what is the direction they like to go? What can this cause?
They often start peripherally and travel towards SC, hence the nerve root signs & monoparesis/plegia
If the tumor continues to the intumnescense it can lead to hemiparesis/plegia. With LMN signs on front limb UMN in hind.
Postural reactions very helpful here!
How is MPNST best diagnosed?
Tx?
Px??
Myelogram
MRI/CT
Resection best but…decr or loss of function of limb & it reoccurs
radiation/chemo may slow down progression after sx
Prognosis not long to live :(
What is fibrocartilaginous emboli?
fibrocartilage (from intervertebral disks) get into b.v and causes ischemic myelopathy
unknown how
Ms. Jones brings in her 5 yo Akita because he was playing out in the yard and she heard him yelp and now he cant use his back legs. she thinks he must have stepped on something. What do you suspect? What will you expect to find to support your ddx?
FCE
3-6 yo Lg/giant breed or maybe a Min Schnauzer/Sheltie
Hx of peracute onset - 60% post/during exercise
No hx of trauma; non-progressive (+/- 6h)
can be mono (rarest form) /bi/hemi or tetra paresis/paralysis depending on where FCE lodged, lateralizing
non painful after initial event on palpation
brachial/pelvic intumescence w/ LMN signs
What diagnostics can help confirm dx of FCE?
Now how will you tx it?
myelogram -nope usually normal, may have swollen cord
MRI- if non ambulatory have 80% chance to see oval (star shaped), hyperintense area of SC
