Neurology 3 - Conditions Involving all Four Limbs Flashcards
What is cervical spondylomyelopathy?
Canine Wobblers, type II disc degeneration at C6/C7 in Dobes and Rotties
Two types of cervical disc disease
type I - hyaline degeneration, disc explodes into cervical SC
type II - canine wobblers/cervical spondylomyelopathy
Most prominent sign of cervical disc disease? A) tetraparesis B) pain C) incontinence D) paralysis
B - pain
the cervical spinal column has more space so a protruding disk doesn’t affect neural function as much as a prolapsed disc in the thoracolumbar region
How would you diagnose type I cervical disk disease?
inject contrast into cisterna magna, should see prolapsed disk and narrowing of spinal column
How would you treat type I cervical disk disease?
cage rest, physio to maintain muscle mass, NSAIDs with prednisone intermittently, can do Sx: modified slanted slot
T/F: there is more spinal cord compression in Wobblers compared to type I cervical disc disease
True because with Wobblers there is bone tipping and the craniodorsal ridge causes a stenosis (whereas in type 1 this is not seen) as well as osteophyte formation into the column
Signalment of Wobblers
Great Danes 3-18m, Dobes 5-8y
Clinical signs of Wobbler’s disease
head guarding, neck pain, pelvic signs (wobbling, paresis), mild CP deficit and stiff gait in forelimbs, atrophy of supra and infra spinatus
An owner brings his Doberman in because the dog is showing signs of severe neck pain. There are no other clinical signs. Is it possible this dog has Wobbler’s?
yes, 15% of cases only sign is neck pain
How can you diagnose Wobbler’s disease?
traction radiographs - tipping, stenosis, rounding, decreased disc spaces, degeneration in articular facets.
dynamic MRI is better
how would you treat Wobblers
each case different
palliative, disease is progressive
can do Sx for decompression, stabilization
How would you treat an upper motor neurone bladder
phenoxybenzamine
prazosin
tamsulosin
What is Atlanto-axial subluxation?
spinal cord decompression due to dorsal displacement of the axis
Signalment of Atlanto-axial subluxation
small breed dogs
dens doesnt develop = instability between C1 and C2
also large breeds exposed to trauma
How would you diagnose atlanto-axial subluxation?
radiographs - don’t manipulate neck
Signs of atlantoaxial subluxation
neck pain to tetraplegia, respiratory paralysis
T/F: hemilaminectomy + wiring/screwing works well on small bones and is 100% effective at treating atlanto-axial subluxation
false
Another name for caudal occipital malformation syndrome
chiari 1 malformation syndrome
What is the main brain lesion seen in caudal occipital malformation syndrome?
cerebellum slips through the foramen magnum, see dilation of central canal caudal to area, pressure damage to spinal cord
Caudal Occipital malformation syndrome seen in 50% of A) Dobermans B) Cavalier King Charles Spaniels C) Yorkies D) Labs
B - CKCS
Treatment for caudal occipital malformation syndrome
Gabapentin, prednisone, FMD (foramen magnum decompression)
Causes of infectious myopathies
toxoplasma
neosporum
Lyme
Hepatozoan
What is canine idiopathic polymyositis
immune mediated disease of large mature dogs
weakness, stiffness, rapid fatigue, atrophy
can see pyrexia, pain, regorge,bark, dysphagia, ventroflexion of head
Tx: immunosuppressants
T/F: can give azathioprine for sparing of prednisone dose (decrease steroid levels) in dogs
True
T/F: cats must receive azathioprine when being treated with prednisone
false, cats are less susceptible to effects of long term prednisone use
Masticatory muscle myositis
large breeds <4y
waxing and waning phases of painful swollen muscles, pseudotrismus fever
Tx with prednisone + azathioprine for steroid sparing effects
Extraocular myositis
autoimmunity to component of extra ocular muscles
golden retrievers and large breeds, 6-18m
bilateral exophthalmos
PO corticosteroids, may need chronic prednisone
Exertional myopathy
post exercise, increased serum CK, renal failure grey hounds and working dogs painful muscles and rigidity Tx with fluid, bicarbonate, rest animals tend to die from renal failure
Hypokalemia
cats with K deficient diets, acidic diet, hyperaldosteronism, hyperthyroidism
CS: persistent ventroflexion of the neck, stiff gait, resistance to move, no neuro deficits
serum CK elevated, K decreased
Tx with oral supplementation
Feline Idiopathic Inflammatory Myopathy
sudden onset of weakness, cervical ventroflexion, inability to jump, muscles may be painful
Tx: prednisone
Limber Tail
pointer sand labs
flaccid tail becomes painful
Tx with NSAIDs and rest
Dystrophic myopathies
young animals
inherited deformities of the skeleton
stunting, weakness, gait abnormalities, trismus, muscle atrophy with fibrosis
Non-dystrophic myopathies
Central Core Like - Danes
Nemaline rod - cats, blue merle border collie
Congenital degenerative myopathies - labs, retrievers, chows, bouviers
muscle wasting, weakness, can’t hold head up
Metabolic myopathies
hypo and hyperthyroidism
hyperadrenocorticism
enzyme deficiencies (glycogen storage disease, phosphofructokinase deficiency)
exercise induced collapse (EIC) in labs
Myotonia
chows, westies, danes, cats
fainting goats
sustained depolarization of muscle fibers
dimbling of muscle, stiff gait, slow CP, clonic reflexes
Dermatomyositis
skin lesions 2-6m then weakness, megaesophagus
resolves, chronic waxing and waning
collies
tx: pentoxifylline
Feline hyperesthesia syndrome
5-8y pure breeds
intermittent, twitching, grooming, agitation, vocalization, running, aggression
allergies, SC lesions, myositis, behaviour changes, seizures
including body myopathy
poor prognosis
Two types of Myasthenia gravis
Congenital (born without Ach receptors) and Acquired (autoantibodies to Ach receptors)
Classical presentation of myasthenia gravis
weakness following exercise
Describe acute. vs chronic myasthenia gravis
Acute - sudden development of flaccid paralysis, hypotonicity, severe regurgitation (predisposes to inhalation pneumonia), weakness, resp failure
Chronic - exercise intolerance, megaesophagus
Diagnosis of myasthenia gravis?
Tension test - inject edrophonium and look for improvement
Best test - AchR antibody test/immune complex
Treatment of myasthenia gravis?
Pyridostigmine increases Ach concentration in the synapse
Congenital and acute cases have poor prognosis
MoA of Botulism?
Botulin toxin blocks Ach presynaptically
CS of botulism
tetraparesis, flaccid paralysis, CN signs, difficulty breathing
Dx of botulism
presence of toxin in faces
Best tx of botulism
supportive care
2 ticks that can cause tick paralysis
dermacentors, ixodes
MoA of tick paralysis
block nerve conduction or decrease Ach
Tx of tick paralysis
remove ticks
Signs of tick paralysis
tetraparesis, LMN signs
cranial nerves, sensation and continence spared
MoA of tetanus
C. tetani neurotoxin enters puncture wound and travels to spinal cord and blocks inhibitory neurons
Signs of tetanus
sardonic facial expression,
whole animal is stiff (cats usually just one limb)
Tx of tetanus
supportive care, Ace to relax muscles, penicillin to kill bacteria, feeding tubes
Acute canine polradiculoneuritis/Coonhound paralysis
inflammation and demyelination of ventral roots
saliva from racoons
ascending LMN paralysis and tetraplegia
cranial nerves, sensation and continence spared
recovery after weeks/months
Protozoal polyradiculoneurititis
toxoplasma or neospoa canine
many dogs subclinical carriers, others show progressive posterior paresis
Dx - send 2 samples a while apart to look for increasing concentration
Tx - trimethoprim or clindamycin
