Neurology 2 - Conditions Involving Both Hind Limbs Flashcards
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
An infection of the end plates and disk is called
diskospondylitis
common etiologies of diskospondylitis?
S. intermedius
B. canis
Strep
T/F: diskospondylitis usually originates in the spinal cord
false, it is usually somewhere else and spreads hematogenously
Clinical signs of diskospondylitis
hyperesthesia, fever, depression, weight loss
T/F: bony proliferation caused by diskospondylitis can cause spinal cord compression
True
treatment for diskospondylitis?
antibiotics based on cluture results, want to use bactericidal drug, PO for 54weeks (until radiographic resolution)
3 locations for vertebral and spinal neoplasia
intramedullary
intradural-extramedullary
extradural
With which type of spinal neoplasia would you see a golf-tee sign?
intradural-extramedullary
best imaging tool to diagnose intramedullary or extradural spinal neoplasia?
radiographs
Best imaging to localize a spinal tumor
MRI and CT
For which spinal neoplasia could it be beneficial to sample the CSF?
lymphomas
Do cats or dogs have better prognosis for a meningioma after resection?
cats (6-12m), dogs are 6m
An owner comes in worried that her toddler hurt her cat when they were playing yesterday. She saw her child pull on the cats tail and it has appeared droopy since then. The cat has also been peeing on the floor. What do you suspect?
tail tug, vertebral luxation
T/F: Shiff-Sherrington can be seen in vertebral fractures and luxations
true
What fluids are best to give an animal with a vertebral luxation?
colloids - would rather draw water out of tissues than give additional fluids and worsening edema
Treatment for an animal with a vertebral luxation/trauma?
Treat shock/life threats first (colloids). Opioids for pain. 20% mannitol to reduce spinal edema. Sx to decompress and stabilize
Large dogs - external coaptation device, small ogs and cats - splinting and rest
Hemivertebrae
bulldogs and Bostons
lack of formation of one hand of vertebrae
Block or fused vertebrae
disc moved but didnt affect spinal cord, vertebrae fuse
Spinal dysraphism
bulldogs and Bostons
spina bifida where spinal column doesn’t properly close, potential for meninges to poke through
Sacrococcygeal dysgenesis
manx cats
lack of development of sacrum and associated nerves
incontinence
Spondylosis
ventral bridging of vertebrae
75% dogs have it by 9y
Old Dog hind limb tremors
any breed, esp terriers and larger breeds
mild in one or both hind limbs
especially when standing or sitting, disappears with movement
treatment not needed is just cosmetic
Dancing Dobermans
6m-7y
contraction of gastrocnemius muscle
normal neuro exam
