Equine Pathology Flashcards
What is Wobbler syndrome and what are the most common causes?
- cervical vertebral malformation/ abnormalities
- Equine degenerative myeloencephalopathy
- Equine Herpes Virus ! myeloencphalitis
- Vertebral Trauma
What is the Type 1 Cervical Vertebral Malformation
Etiology
Therapy
Malformation with stenosis of vertebral canal
- absolute, occuring with neck in any position
- dynamic, occuring more in flexion (C2-C6) or extension C6-T1)
- Malformation with abnormal formation of and alteration to the articular process (caused by osteochondrosis)
- Enlarged vertebral physeal growth regions
Etiology
- Heritability
- Physical stress and trauma
- Nutrition
- multifactoral disease
Therapy:
-Suregery (cervical vertebral fusing using a stainless steel basket
-Corticosteroids
-Chiropractic -adjustment of cervical subluxations can improve symptoms but not cure problem
Prognosis is varied.
Type 2 Cervical Vertebral Malformation (CSS/ CVSM)
Etiology
-older patients
-sever osteoarthritic enlargement of cervical vertebral articulr process
-no evidence of developmental defects
-stenosis of vertebral canal by proliferating bone soft tissue assosiated with degenerative joint idsease
-peridural and epidural synovial cysts.
Ageing patients.
Etiology:
- DJD
- biomechanical dysfunction
- external injury is considered important factor (repetative)
Equine Herpesvirus
Whats it look like
• Equine Herpesvirus Type 1
• Acute onset of ataxia or recumbency (1 week after
exposure)
• Symmetric pelvic limb ataxia and paresis
• Urinary bladder paralysis, overflow incontinence
• Prognosis: guarded when recumbent
Vertebral Trauma
Whats it look like
• Signs usually peracute and non progressive
• Not always neurological signs with vertebral
damage
• Neurological signs can occur without bony damage
• Fractures
• Hairline fractures
• Luxations with soft tissue damage
Traumatic Atlantoaxial Luxation
• Ruptured ligaments of the dens • Dens luxates ventrally • Soft tissue damage • Not always with neurological deficits (diameter of spinal canal)
Headshaking
multiple etiologies
How is it diagnosed
therapy
- Repetitive, sudden, jerky movements of the head
- Rubbing the nose/nostrils at the legs
- Sometimes with snorting/sneezing
- Mainly in spring and summer
- Increase of symptoms with sunlight, heat, insects, pollen
Huge involvement in trigeminal nerve, likely to accompany it
-generally behavioural issues is generally some kind of discomfort or pain.
Its response to pain
•skin infection
•ear mites
•guttural pouch infection •diseases of cranial nerves •ear infection
•teeth problem
•ill fitting snaffle
• allergy
•EHV-1 infection? •melantonin?
•...
triggered by:
• sunlight • insects • wind
• cold
• dust
• raindrops
Diagnosis
• eye, ear and teeth examination
• x-ray head, upper cervicals, teeth, TMJ
• endoscopy of nose, trachea, pharynx/larynx, guttural pouch
• allergy test
• CT or MRI
Therapy • carbamazepine (cyproheptadine) • avoidance of direct sunlight and insects • face mask • riding early morning/evening • cover for nostrils
Autonomic Nervous system Dysfunction
Diagnostic work- up should proceed chiropractic
-concurrent care may be needed
Horner Syndrome
Clinical Signs
Etiology
Therapy
Lesions in sympathetic ganglion at T1 –T3
• Lesion in sympathetic chain ganglion in cervical region
facial asymmetry and drooping and eye ptosis
• Loss of Sympathetic innervation to the eye • Myosis or pupil constriction • Enophthalmos or retraction of eyeball • Prolapse of the third eyelid • Ptosis or droop of upper eyelid • Anhydrosis of the eye • Unilateral sweating in upper cervical region may see localised sweating also
Etiology:
- Cervical trauma or lesion at T1 –T3
- Tumor in thoracic inlet, mediastinal tumors
- Inflammation of the guttural pouch (horses)
- Brachial plexus avulsion
- Perivascular injection
Therapy:
- depends on Etiology
- chiropractic (adjustment of cervical or upper thoracic subluxations
- prognosis depends on etiology
Idiopathic Epilepsy
What is it
Symptoms
Other possible causes
Therapy
- Seizures are defined as abnormal motor or behavioral activity arising from the brain as a result of dysfunction in the frontal cortex
- Primary epilepsy which is characterized by recurrent seizures without abnormalities in clinical tests and suspected genetic disposition is rare in horses (study from 2012: 104 horses, 2 classified as idiopathic)
Symptoms • Chewing, licking • twitching muscles • sweating • paddling of legs • sudden collapse • loss of consciousness Seizure normally followed by gradual return to normal
Other possible causes
• Viral or bacterial infections • Tumors
• Trauma
• Oxygen deprivation (foals) • Toxins
Therapy • Traditional • Anti-convulsants • Phenobarbital, Diazepam • Chiropractic Treatment goals: • Reduce frequency, severity and pre-seizure symptoms • Reduce medication dosage
Performance Problems
- Decreased cervical flexion
- Decreased cervical bending
- Headtilt/carriage
- Unspecific lamenesses
- Decreased forelimb stride
Large amount of patients we will see much of these issues ie cant bend one way properly, cant flex or other, head tilt to one side, non-specific lameness.
Cervical Arthritis/ Arthrosis
What it looks like
Therapy
Diagnosis
Clinical examination Motion palpation:
• Decreased ROM
• Pain
Radiography / Scintigraphy findings / CT scan
• 80% of findings between C5 and T1 !!! Thorough examination! Exclude other factors!
Therapy: NSAIDS/ corticosteroids systemically -intraarticular injection of corticosteroids -Chiropractic -Management: training, low hey feeding
Disc Degeneration
Highest incidence is C5-T1, then L4-S1.
Thoracic Limb Lameness
What is it, what happens?
How does it show in a clinical lamenss exam?
-85% of forelimb lamenesses are carpal or distal!
Brachial plexus lameness
• Between scapula / shoulder joint and
lower cervical/upper thoracic spine ( C6-
T1)
• Irritated nerves in lower cervicals
Irritated nerves in lower cervicals going into forelimb.
-Seen some cases that have gotten much better with Chiro, but also it increases lamness as it gets rid of the compensations.
Clinical lameness exam:
• Intermittend lameness
• ‚Tranter‘- looks like its about to break into a canter, but it isnt.
• Associated with head/neck carriage
• Issues in the distal limb need to be excluded
Facet Syndrome
- Irritation of joint/ joint capsules
- Exacerbated with extension of the spine
- Caused by subluxations and mechanical stress on joint such as over-extension
- Chiropractic care
- Concurrent care?
