Canine Pathology Flashcards
Congenital Abnormalities
• Congenital Torticollis
– Malformation of more caudal cervical vertebra
• Vertebral body fusion
• Malformation of the atlantoaxial joint in dogs
– Agenesis or hypoplasia of the dens – Non union of dens, fracture of dens
Atlantoaxiale Instability
Clinical Signs
Therapy
• Allows excessive flexion of the joint Subluxation
Traumatic spinal cord injury and compression Toy or miniature breeds
When breed so small, something gives and can often be here. May present with a sort of insignificant trauma, and will be in agony, screaming unable to make movements of necks. Will be very sore apon palpation.
Atlantoaxiale instability
Clinical signs
• Acute or chronic onset
• Progressive, nonprogressive or intermittent
• Cervical pain can occur
• within the first year of life
• Severity varies from mild to profound cervical pain, tetraparesis, respiratory paralysis and caudal brainstem signs
• Therapy • Surgical decompression and stabilization • Not before 6 month of age • Success rate varies from 79% to 92% (good to excellent outcome) • Therapy • Conservative • Mild symptoms • Splinting head and neck in light extension • Cage rest for 6 weeks • Medication • Physiotherapy • Controlled exercise • Chiropractic?
Syringomyelia in Cavalier King Charles Spaniel
What is it?
- Syringomyelia (SM) is an extremely serious condition in which fluid-filled cavities develop within the spinal cord near the brain.
- “neck scratcher’s disease“
- no symptoms until 6 months age
- back half of the King Charles spaniel’s skull too small to accommodate all of the cerebellum, which may also be too large, and so it squeezes through the foramen magnum
- Cerebellum is partially blocking the flow of CSF down the spinal cord
- The variable pressure created by the abnormal flow of CSF is believed to create the SM cavities – called syrinx – in the spinal cord.
- rare in most breeds, but very widespread in King Charles Spaniel and Brussels Griffon
Cervical Spondylomyelopathy
- Wobbler Syndrome -
What is it
Etiology
Cervical Spondylomyelopathy
- Wobbler Syndrome -
Common disease of cervical spine in large or giant breed dogs
Dynamic or static compression of the cervical spinal cord, nerve roots or both
Variable neurological deficits neck pain
Controversial disease…
Etiology:
Stillunknown Genetic??
– No well-designed prospective study Congenital
Shown in Dobermans (Burbidge HM, 1999) Body conformation
– No significant role in development of CSM (Burbidge HM, 1999)
Nutritional
– Overfeeding and calcium supplements in Greate Dane (Hedhammar,
1975), (Hazewinkel HA, 1985)
– No significant role in dobermans (Burbidge HM, 1999)
– Chronic progressive cervical myelopathy
– Malformed structures
– static lesions are typical in young large breed dogs (Great
Dane, Mastiff) usually secondary to malformed
structures
– Degenerative disc disease typical in Dobermanns (C5-6,
C6-7)
Stenosis of Vertebral Canal (C5, C6, C7)
Diagnosis- Clinical Signs
Diagnostic imaging
Treatment of CSM
Spondylolithesis
• Congenital malformation off acetsor spinal canal • Hyperplasia of ligamentum flavum
• Hyperosthosisofvertebrallamina
Diagnosis: Clinical Signs
Chronic progressive history
• Neck pain or cervical hyperesthesia
• Supraspinatus muscle atrophy, dorsal neck muscle hypertrophy
• Ellbow abduction with internal rotation of the digits (30% of CSM Dobermans)
• Gait evaluation!!
– „2-engine-gait“
– Short-strided thoracic limb gait with a wide-based, long-strided pelvic limb gait
– Slow pace
• Scuffing of the pelvic or thoracic limb toes • Proprioceptive deficits
• X-ray / Myelography
– Dynamic effects of traction, flexion and extension
• CT
• MRI (Gold standard)
• Continuing source of discussion • Surgical techniques (70 – 90 % with good outcome) • Conservative treatment • Acupuncture • Physiotherapy • Chiropractic?? • Exercise restriction • Body harness!! • Medical management: – Corticosteroids (0,5-1mg/kg every 12-24hrs) (no scientific evidence!!) – NSAIDs – Omeprazol
Cervical Spine Trauma
• Vertebral fracture • Vertebral luxation • Disc prolaps - rarely • Suspected Trauma – CAVE!!! – Extreme caution with chiropractic treatment – Short neurological examination – Diagnostic imaging
Cervical Disc Disease:
Disc Extrusions- Type 1
Disc Protrusion- Type II
Intervertebral disc disease
Degeneration of intervertebral disc ->
Prolaps of intervertebral disc –> Compression of spinal cord
Hansen Type I Disc extrusion
• Acute prolaps
• Rupture of outer fibroid layer of anulus fibrosus
• Parts of nucleus pulposus bulge out into vertebral canal
• Ischemic lesion of spinal cord
IVD Extrusion - Hansen Type I - – Small, chondrodystrophic breeds – Acute or chronic history, painfull, neck spasm – Treatment: • Conservative in dogs with no neurological signs • +/- analgesia • Surgical decompression – Prognosis: good to excellent
Hansen Type II Disc protrusion
• Chronic prolaps
• Prolapse of dorsal, outer fibroid layer of anulus fibrosus into vertebral canal
• Dorsal displacement of nucleus
• Progressive demyelination and injury of white substance of spinal cord
IVD Protusion - Hansen Type II - – Larger breeds – Typically chronic or intermittend history of neck pain/difficulty walking – C5-6 or C6-7 – Pelvic limb paresis/ataxia – Treatment: • Surgical decompression • Dynamic component - distraction and stabilization?? – Fair to good
What does progressive neurological Symptoms look like?
Proprioception loss > Paresis > motor control > bladder function > sensibility
IVD diagnosis- how is it diagnoses?
IVD treatment
Surgical treatment
Conservative TX
- Xray
- Myelography
- CSF (CSF) Analysis
- CT
- MRI
IVD Treatment
Depends on individual dog‘s neurological status Medical treatment
– Corticoids ONLY in acute onsets of neurological deficits within 8 hours (obsolete)
Conservative
– Rest for minimum 2 weeks (?)
– no improvement after 7 to 10 days -> further
evaluation (Myelography, X-rays, surgery)
Surgical Treatment
Severe neck pain, neurologic deficits
Recurrence or deterioration of clinical signs after medical management
Chronic history
Fenestration of disc DOES NOT remove disk material from the spinal canal (not recommended as the only surgical procedure in a dog!!) (Seim HB, J Am Anim Hosp Assoc, 1982)
Decompressive procedure:
– Ventral slot decompression
– Dorsal laminectomy or hemilaminectomy – Lateral approaches (C3-C6)
Conservative treatment
50% managed successfully (Levine JM et al, Vet Surg 2007) – Exercise restriction (small cage??, 2 to 6 weeks - healing of
anulus fibrosus)
Physiotherapie
Medication (analgesics, corticoids??, muscle relaxants…)
– 50% managed successfully
– NSAIDs were associated with successful outcome, steroid use
and cage rest NOT (Levine JM et al, Vet Surg 2007) Harness instead of neck collar
Acupuncture
Chiropractic ???
The acute neck / screaming dog syndrome
What can cause it
- Acute vertebral subluxation complex
* Intervertebral Disc • Facet-Syndrome
Autonomic Nervous System Dysfunction
- Organ dysfunction preceeding pathology
- Concurrent care may be needed
- Diagnostic work-up should preceed chiropractic care
Horner Syndrome
Etiology
Clinical Signs
Therapy
- Lesions in sympathetic ganglion at T1 –T3
- Lesion in sympathetic chain ganglion in cervical region
Etiology • Cervical trauma or lesion at T1 –T3 • Otitis media • Tumor in thoracic inlet, mediastinal tumors • Brachial plexus avulsion
Clinical Signs
• 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
• Depending on Etiology • Chiropractic
– Adjustment of cervical or upper thoracic subluxations
Lick Granulomas
What are they and why do they happen?
• Paresthesia from radiculopathy
• Bad habit, boredom • Clinical Signs
– Open lesions on the anterior surface of front leg
– Constant chewing and licking at lesion
Discospondylitis What is it? What are the primary sources that are possible? Symptoms? How do you Diagnose it?
therapy and prognosis?
• Inflammation or infection of the intervertebral disc and osteomyelitis in adjacent vertebral end plates and bodies
• Staphylococcus (S. aureus or S. intermedius), Brucella canis
• Primary sources:
– Urogenital tract – Skin
– Dental diseases – heart
– Debris – Wounds – Surgery
Symptoms: – Hyperaesthesia – Paresis/Paralysis possible – Signs of infection (fever, decreased state of health, Anorexia) are possible
• Diagnosis:
– DIFFICULT!!
– Radiography (complete spine)
• Compression of intervertebral space
• Lysis of surface of the intervertebral joints • Sclerosis of adjacent vertebral cortex
– Haemo diagnosis
– Needle aspiration cytology of intervertebral disc
– Differential diagnosis: vertebral tumor
Therapy:
• Therapy
– Aggressive antibiotic therapy for at least 2 to 4 months
– Analgesics • Prognosis
– May be guarded in dogs by fungal infections or infections with B. canis
Meningitis
Clinical Signs
• Clincal signs
– Only painful and reluctant to move
– If spinal cord is affected - additional neurological deficits
(paresis, proprioceptive deficits)
– Signs of infection (fever, decreased state of health,
Anorexia) are possible
• Bacterial or SRMA (steroid-responsive meningitis-
arteritis)
