Neurology 2 - Conditions Involving Both Hind Limbs Flashcards
(47 cards)
What is degenerative myelopathy
degenerations of axons and myelin in the thoracolumbar spinal cord, causing unilateral or bilateral paresis/paralysis
Cause of degenerative myelopathy?
thought to be genetic
Signalmet for degenerative myelopathy
> 8years old German Shepherds
also Chesapeake, boxer, corgi, ridgeback, poodle, Kerry blue
Signs associated with degenerative myelopathy
pelvic limb: knuckling, dragging, crossing, dysmetria, ataxia
often asymmetrical
continence and pain spared
later get LMN signs
PE findings of a dog with degenerative myelopathy
CP deficits, UMN signs in the hind limb (hyperreflexia, normal pain sensation), no spinal hyperesthesia
How would you diagnose degenerative myelopathy
signalment, histopathology, exclusion, DNA test for superoxide dismutase 1 protein
Treatment for degenerative myelopathy
none, can give supportive therapy + physio but inevitable euthanasia
What type of disc degeneration is involved with lumbosacral degenerative stenosis?
type II disc degeneration
What compresses the spinal cord in lumbosacral degenerative stenosis?
ventrally: annulus fibrosis
dorsally: ruptured interarcuate ligament heals by scar tissue formation (fibrosis)
osteophytes
Which part of spinal cord is affected by lumbosacral degenerative stenosis?
cauda equina, L7-S1
Signalment of lumbosacral degenerative stenosis
older, large breeds, working dogs
Signs of lumbosacral degenerative stenosis
hunched, flaccid tail, later see incontinence, sunken hock
pseudohyperreflexia of patella reflex (no resistance from mm. on back of leg, sciatic n.)
cannot flex hock or knee (sciatic n.)
LMN of pudendal n.
A dog comes into your clinic presenting with a hunched back. You conduct radiographs and notice a lumbosacral step as well as a transitional vertebrae. What are your treatment options?
This is characteristic of lumbosacral degenerative stenosis. Treat with cage rest and NSAIDs for pain. Can consider doing dorsal laminectomy +/- joint stabilization with pins
Where do you inject contrast media for a myelogram?
into the CSF
Hansen Type I and II are subcategories of?
Thoracolumbar intervertebral disc disease
T/F: The nucleus pulpous appears more ventral when comparing to the vertebrae
False, more dorsal which is why if it prolapses it goes dorsally
Hansen Type I thoracolumbar intervertebral disc disease
explosive extrusion, calcified hyalin cartilage ruptures through fibrosis and dorsal longitudinal ligaments into spinal canal hitting CS, “bullet like”
seen more in chondrodystrophic breeds
Hansen Type II thoracolumbar intervertebral disc disease
Slow protrusion of annulus fibrosis into spinal cord due to continuous tear and healing by fibrosis
seen more in large dogs
Clinical signs of Grades 1-5 thoracolumbar intervertebral disc disease
1 - spinal hyperesthesia w/o neural deficits 2 - paresis but ambulatory 3 - paresis but non-ambulatory 4 - paralysis + deep pain intact 5 - paralysis with loss of deep pain
What is the order that you would lose nervous function?
conscious proprioception
voluntary motor + continence
superficial pain sensation
deep pain sensation
You are looking at a radiograph of the spine of a dog that you have diagnosed with type 1 thoracolumbar intervertebral disc disease. What would you expect to see between the vertebrae of the affected area?
The nucleus pulposus would have ruptured dorsally into the spinal canal, so the two vertebrae should appear closer in proximity compared to the rest that still have nucleus pulposus between them
How would you treat a dog with grade 1-3 thoracolumbar intervertebral disease?
strict cage rest, conduct physio. if no improvement in 2weeks, surgery
How would you treat a dog with grade 4 thoracolumbar intervertebral disease?
strict cage rest, will need to manually express bladder. Surgery (dorsolateral hmmilaminectomy + fenestration) is best
How would you treat a dog with grade 5 thoracocolumbar intervertebral disease?
Dorsal hmmilaminectomy and durotomy, poor prognosis