Lecture 5: Diseases of nervous system: inflammatory/degenerative Flashcards
What is the cause of equine degenerative myelopathy/ neuroaxonal dystrophy
temporal vitamin E deficiency within 1st year of life
what horses have genetic susceptibility to equine degenerative myelopathy
quarter horses, Morgan’s and thoroughbreds
what are some signs of equine degenerative myelopathy
young horse with symmetrical ataxia, paresis, wide based stance, pacing
how do you dx equine degenerative myelopathy
- Low serum vitamin E
- Rule out other differentials
- Necropsy for definitive dx- central axonal degenerative projected in somatosensory tracts
what is tx for equine degenerative myelopathy
natural source alpha tocopherol 5000 IU/day
how do you prevent equine degenerative myelopathy
feed 1-2IU/kg vitamin E for first 3 years of life
what is prognosis for equine degenerative myelopathy
poor response even if caught early
what is etiology of equine motor neuron disease
disease of adults after prolonged vitamin
E deficiency that predisposes to oxidative stress or neurological system resulting in denervation of skeletal muscle
what are some signs of equine motor neuron disease
feet close together, elevated tail head, low head carriage, shifting weight, walking can induce muscle fasciculations, nostril flare and sweating
No ataxia
how do you diagnosis equine motor neuron disease
- Biopsy of dorsal coccygeal muscles- sacrocaudalis dorsalis
what is tx for equine motor neuron disease
natural alpha tocopherol 5000 IU/day
What horses have genetic predisposition for cervical stenotic myelopathy (wobblers)
Thoroughbreds, warm bloods, Tennessee walking horses
Males over presented
Young well feed, rapidly growing horses
what are the copper and zinc levels in wobblers
low copper, high zinc
what causes wobblers
ataxia induced by developmental abnormality and degenerative conditions of cervical vertebrae
what is dynamic/ type 1 wobblers
Unstable, affects 6-18 months old
what is static/type 2 wobblers
compressive affects 3-5 year olds
what are the most common sites affected by wobblers
- C3-C4
- C4-C5
- C5-C6
how do you dx wobblers
- Ataxia worse behind than in forelimbs
- Wobbler heels (scabs from hind limbs hitting front)
- <0.5 ratio C4-C6, <0.52 ratio C7, malalignment on rads
what is the medical tx for wobblers
- Cervical facet injections
- Slowed growth via restricted calorie diet
- Rest, no herd mates
what is the sx tx for wobblers
vertebral fusion
what is the etiology of cervical articulate facet arthritis
mild cases of wobblers that worsen with age or trauma
what are some signs of cervical articulate facet arthritis
+/- spinal ataxia, hind limbs worse than forelimbs, stiff neck
how do you dx cervical articulate facet arthritis
rads- show enlarged facets
middle aged horse presents with stiff neck and mild ataxia. What is problem based on rads
Cervical articulate facet arthritis
Facet to the right much larger than facet on left
what is tx for cervical articulate facet arthritis
- Cervical facet injection
- NSAIDS
- Gabapentin
what wrong
C2 fracture
what are some signs of spinal cord trauma
pain, reduced mobility, abnormal neck position, +/- neurological signs
how do you dx spinal cord trauma
- Localize lesion
- Rads
- Fracture sometimes palpable
what is conservative tx for spinal cord trauma
- Analgesia - NSAIDS, butorphanol, lidocaine or ketamine CRI
- Anti-inflammatories
- NSAIDS, steroids
what is sx tx for spinal cord trauma/ fracture
stabilize fracture with implants and prevent large callus formation
what is the prognosis for spinal cord trauma that resulted in immediate tetraplegia with loss of deep pain
grave prognosis and immediate euthanasia warranted
what is prognosis for spinal cord trauma without neurological dysfunction
fair to good prognosis
what is the prognosis for spinal luxations or fractures of vertebral body
guarded to poor
what can cause osteomyelitis
strangles, tuberculosis, brucellosis or extension of soft tissue infection
what are some clinical signs of osteomyelitis
pyrexia, stiff neck, pain, abnormal neck posture, poor appetite, weight loss
what are some blood work findings consistent with osteomyelitis
leukocytosis, neutrophilia and hyperfibrinogenemia
what is tx for osteomyelitis and prognosis
aggressive antimicrobial tx but guarded prognosis
horse recently recovered from strangles, presents with stiff neck and fever. What is likely wrong based on rads and signs
Osteomyelitis
what is the etiology of shivers
degeneration of cerebellar Purkinje cell axons
who is most affected by shivers
male warm bloods, thoroughbreds and tall breeds
what must you do in PPE to evaluate shivers and failure to do so can result in malpractice
back them up
what are some clinical signs of shivers
hypertonic muscle contractions and protracted abduction and hyperflexion of hind limbs when walked backwards
what is tx for shivers
- Vitamin E- neuroprotectant and antioxidant
- PT
what is stringhalt associated with
weeds or trauma to sensory nerves of limbs or unknown
stringhalt is only evident at what gait/speed
walk
what other disorder is commonly seen with stringhalt
laryngeal paralysis
what is tx for stringhalt
remove weed
Lateral digital extensor tenectomy
what causes fibrotic myopathy
damage and scarring or fibrosis of semi membranes is or semitendinosis muscle
what are some signs of fibrotic myopathy
interrupted anterior phase of the stride “goose stepping”
what causes upward fixation of the patella and what is the resulting sign
poor quadriceps tone causes the medial patellar ligament to get aught on medial trochlear ridge and maintain extension via “stay apparatus”
what are some tx for upward fixation of patella
- Conditioning
- Tendon splitting
- Cutting- don’t really do this
what is the pathophysiology of polyneuritis equi
progressive granulomatous polradiculoneuritis involving cauda equine, cranial nerves and other spinal nerves
cause is unknown but theorized to be ___ because of __present
allergic neuritis, P2 myelin protein antibodies
what are some signs of polyneuritis equi
dysuria, tail rubbing, loss of skin sensation in ind end, hyperesthesia, paralysis of tail, bladder, rectum, anus, penis, fecal retention and overflow urinary incontinence, CN abnormalities
what is the definitive dx fo polyneuritis equi
necropsy- nerve roots have granulomatous inflammation and mixed cell infiltrate leading to myelin/axonal degeneration and distortion of fibrous tissue
what are some differential dx for polyneuritis equi
fractures of tail head/ sacrum, pelvis, EPM, EHM
what is tx for polyneuritis equi
- Supportive/ palliative
- Fecal removal and catheterization
- Steroids
what is prognosis for polyneuritis equi
grave
what is the promising diagnostic biomarker for neurological disorders
phosphorylated neurofilaments- H (Pnf-H)
