Spinal disease - Problem solving - vidoes

Question 1

Define FCE

Answer 1

Fibrocartilagenous embolism

Question 2

Define ANNPE

Answer 2

Acute non-compressive NP extrusion

Question 3

What is ANNPE?

Answer 3

o = hyperacute extrusion of hydrated and non-degenerated NP through small fissure in annulus fibrosus, spinal cord contusion but no compression. Don’t confuse with IVDD

Question 4

Other names - ANNPE

Answer 4

: high velocity, low-volume disk extrusion, traumatic intervertebral disc extrusion.

Question 5

What is the typical signalment and history for both FCE and ANNPE?

Answer 5

o Adult large breed dogs
o Hyperacute onset of CS (seconds)
o Occurs during strenuous activity or external trauma for ANNPE
o Typically non-painful (FCE

Question 6

Ddx - 7 yo ME Doberman Pinscher, chronic, painful, progressive, non-lateralising C6-T2 myelopathy

Answer 6

o CIVDD (type 1 or 2)
o Cervical spondylomyelopathy
o Neoplasia
o Cervical spondylomyelopathy (many terms in literature, this is correct term)

Question 7

What is cervical spondylomyelopathy?

Answer 7

• Complex neurological syndrome

* Covering term: describe cervical vertebral canal stenosis d/t soft tissue and bony structure

Question 8

Animals affected by cervical spondylomyelopathy

Answer 8

• Large and giant breeds

Question 9

CS - cervical spondylomyelopathy

Answer 9

• Variety of CS, lesions, synonyms
• These are perhaps distinct clinical syndromes (?)
• Cervical hyperaesthesia, ataxia, paresis
• Wide-based ataxia and paresis of HL in combination with short-stilted gait of TL  ‘disconnected’ or ‘two-engine gait’

Question 10

What are the 2 forms of cervical spondylomyelopathy?

Answer 10

Disc-associated cervical spondylomyelopathy and osseous-associated cervical spondylomyelopathy

Question 11

Typical dog affected by Disc-associated cervical spondylomyelopathy

Answer 11

o Older large breed dogs (>6yo)

o Doberman Pinscher

Question 12

What happens in disc-associated cervical spondylomyelopathy?

Answer 12

o Intervertebral disc protrusion(s) – one or more caudal cervical, C6-C7 and C5-7 most commonly affected
o Vertebral abnormalities: abnormal shape and position of vertebral bodies
o Ligamentum flavum hypertrophy ( mid-dorsal extradural compression)
o C5-C6 and C6-C7
o Multiple compression sites in 25-50% cases
o Multifactorial syndrome

Question 13

What are the side effects of myelography? Incidence?

Answer 13

 Post-myelographic seizures (27%)

 Neurological deterioration (14%)

Question 14

Tx - disc-associated cervical spondylomyelopathy

Answer 14

 Controversial, surgical and medical options
 Surgical
• > 20 techniques reported
• Most authors claim 75% success rate
• Up to 25% will demonstrate a recurrence of CS after initial improvement (adjacent segment disease or ‘domino lesion’)
 Medical
• 40% asuccess
• Failure characterised by rapid deterioration

Question 15

What dogs does osseous-associated cervical sponylomyelopathy affect?

Answer 15

o Young-adult giant breeds (18-24 months)

o Great Dane, Dogues de Bordeaux

Question 16

What happens in osseous-associated cervical spondylomyelopathy?

Answer 16

o Articular process abnormalities (hypertrophy/ degeneration. Causes dorsolateral or lateral SC compression)
o Ligamentum flaum and dorsal lamina hypertrophy ( dorsal compression)
o Ventral abnormalities too
o Also more cranial sites
o Multiple sites in 85%

Question 17

What is the imaging modality of choice for cervical spondylomyelopathy?

Answer 17

• MRI is the imaging modality of choice, preferred over myelogram (25% (Dobermans?) have seizure when recover from anaesthesia)

Question 18

If only HL is affected, where is the spinal lesions?

Answer 18

T3-L3 or L4-S3 (then look for spinal reflexes and mm tone to differentiate)

Question 19

Ddx - pug puppy with progressive neurological deficits - 3

Answer 19

1. Arachnoid diverticulum
2. Vertebral malformation – hemivertebra, kyphosis
3. Infectious inflammatory – CDV, toxoplasmosis, neosporosis

Question 20

What is spinal arachnoid diverticulum?

Answer 20

= focal fluid filled dilations of the subarachnoid space  progressive SC compression

Question 21

Aetiology - arachnoid diverticulum

Answer 21

• multifactorial (congenital or acquired)

- pug and french bulldogs

Question 22

Sx - arachnoid diverticulum

Answer 22

Sx- challenging, incise into cyst to collapse it

Question 23

Dx - arachnoid diverticulum.

Answer 23

• myelography,
• CT-myelography
• MRI.
• Look for typical teardrop-shaped dilatation subarachnoid space

Question 24

What is the commonest vertebral malformation?

Answer 24

hemivertebra

Question 25

Breed predisposition - hemivertebra

Answer 25

bulldogs, pugs. Up to 78% clinically normal French Bulldogs have radiographic evidence of hemivertebra

Question 26

Describe hemivertevra

Answer 26

Incomplete formation of vertebral body  wedge shaped vertebral body - Mid thoracic region (T5 and T8) - Vertebral canal stenosis, instability with subluxation and abnormal angulation of the vertebral column - Often mild CS, which can stabilise

Question 27

What can hemivertebra be associated with?

Answer 27

other spinal disorders – IVDD, spinal arachnoid diverticula, syringomyelia, myelitis Hemivertbera often an incidental finding

Question 28

What is the occurence of CS with hemivertebra associated with?

Answer 28

degree of kyphosis

Question 29

Tx - hemivertebra

Answer 29

Sx – spinal sx to correct kyphosis (plates and screws)

Question 30

Ddx - horse with spinal ataxia

Answer 30

* CVM/S = Cervical vertebral malformation/ stenosis = commonest * EHV-1 myeloencephalitis (CS this afternoon) * EDM = equine degenerative myeloencephalitis * Trauma * Migrating parasites (rare UK) * EPM = equine protozoal myeloencephalitis (USA) * (Foreign imports) * Ryegrass staggers (occasionally UK, warmer and damper climates – NZ, fungus which infects ryegrass)

Question 31

CVM/S pathogenesis

Answer 31

* Neuro signs results from progressive SC compression * 2 main types: 1 (dynamic) and 2(absolute – i.e. occurring all time) * Damage ascending proprioceptive and descending motor fibres * When neck flexed or hyperextended, vertebrae move excessively  cord compression. Usually C3-5, usually young animals. Often worse with flexion (C3-C5) and extension (C5-C7)

Question 32

When do you use a myelogram for CVM/S?

Answer 32

uncommon, usually when sx being considered, dye injected dorsally and ventrally (provided dorsal dicolumn is not narrowed, compression of SC unlikely)

Question 33

What is absolute stenosis (type 2)

Answer 33

* = osseous change in vertebrae  SC compression * Usually older horses, C5-7 * Osteoarthritic changes in articular process joints (Facets) as result of congenital OCD - perhaps? * Other malformed vertebrae

Question 34

What spinal congenital malformations can horses get?

Answer 34

* Seen occasionally * Abnormal atlas –fused to back of occiput * Axis – weird shape and fused too * = occipito atlanto-axial malfomation (foals, possibly genetic in Arabians)

Question 35

What is torticolis and how do you diagnose it?

Answer 35

= twisted neck | Dx - lateral radiograph

Question 36

What is articular process joint osteochondrosis?

Answer 36

• Some changes in neck occur due to this • Any articular cartilage joint susceptible • Usually this  OA  type 2 CVM/S OA in neck usually  CS of ataxia Intervertebral foramina = exit for spinal nn

Question 37

What is Wallerian degeneration and what is it associated with?

Answer 37

= distal end of axons, below site of compression, start to die (ventral funiculus lesions predominate). D/t distal ends of axons are separated from cell body. - CVM/S

Question 38

Dx - CVM/S

Answer 38

- Myelography – look for changes in dicolumns in ventral and dorsal part of spinal column, referral only, low sensitivity and low specific --> suspect wobbler syndrome, most cases don’t need this (dx – based on PE, neuro exam and lateral neck radiographs). High specificity with lesions at C6-7. - CT – only reaches to C4 (often compression in cd neck, so not worth risk of GA) - CSF analysis – lumbosacral area, to r/o other dz, usually a referral, iatrogenic haemorrhage a common complication--> confuses interpretation. Normal in CVM/S. - Scintigraphy – not useful for most CVM/S cases but for evaluating spine curvature.

Question 39

Tx and prognosis of CVM/S

Answer 39

* PACE DIET – young, fast growing horses (TBs), protein intake limited (75-80% normal to slow growth), balance properly (minerals etc.) * ARTICULAR PROCESS JOINT MEDICATION – usually corticosteroids into joint, not helpful if bony changes * VENTRAL STABILISATION –limited to certain referrals, GA, dorsal recumbency, incision along middle neck. Drill out compression b/w adjacent vertebrae and screw in titanium implant to stop vertebrae rubbing. Good for dynamic CVM/S also good for static type (but longer). Also many post-op complications. £10,000-12,000.

Question 40

What does the standing tail pull assess?

Answer 40

LMN in lumbosacral plexus

Question 41

What does the walking tail pull assess?

Answer 41

UMN

Question 42

What is implied by gluteal mm atrophy being neurogenic?

Answer 42

implies damage to peripheral nn or cell bodies in ventral horn of SC L3-S3 (i.e. LMN problem in gluteal region of SC

Question 43

Outline occurrence of EPM

Answer 43

- common in USA and S. America • Elsewhere if imported (endemic) • No seasonal influence • About 50% USA horses are sero+ (hard to diagnose those with dz)

Question 44

Outline Sarcocystis neurona

Answer 44

- can cause EPM, animals seroconvert so not all have EPM o Cycles between birds and opossums (= DH, cats =IH) o Faecal contamination of pasture/feed horse (aberrant host) o Not horse-horse spread o Diffuse, multifocal, asymmetric, non-suppurative inflammatory lesion, brain + SC o White + grey matter o Localisation  many different CS

Question 45

CS - EPM

Answer 45

``` o Insidious or sudden o Highly variable – can mimic most other neuro dz o Asymmetric, sensory, motor (UMN or LMN) signs possible o Ataxia o Paresis o Mm atrophy o CN signs (sometimes) o Above CS on own or in combination ```

Question 46

Dx - EPM

Answer 46

o CSF analysis (usually) – occasionally mild mononuclear pleocytosis, often normal o Western immunoblot for S.neurona Abs (CSF and serum levels compared). If leakage of blood into CSF  false positive (as 50% horses seropositive in USA).

Question 47

Tx - EPM

Answer 47

o INHIBITORS OF FOLATE METABOLSIM: sulfadiazine + pyrimethamine (for 3 months) o COCCIDIOSTATS: Ponazuril (Marquis, orally, 3-4 weeks) o NSAIDs (d/t inflammatory component) o STEROIDS (if v acute onset)

Question 48

Prognosis - EPM

Answer 48

o Guarded to poor (especially severe case) o Mm atrophy usually permanent o Ataxia can improve

Question 49

What is the panniculus/ cutaneous trunci reflex used to identify?

Answer 49

used to ID segmental SC lesions

Question 50

What horses does EDM affect?

Answer 50

- various breeds - clusters in certain farms (familial presentation - likely genetic basis) - 6months - 2 years - rare

Question 51

CS - EDM

Answer 51

o Symmetric ataxia o Weakness o HL > TL o Hyporeflexia over trunk (reduced or absent ++)

Question 52

Pathophysiology - EDM

Answer 52

* Neuronal fibre degeneration and demyelination in white matter in ascending and descending tracts * Mid-thoracic region often worst affected * Degenerative lesions in spinal and brainstem nuclei (but classically spinal ataxia)

Question 53

What may EDM be associated with?

Answer 53

May be associated with vit E deficiency / other antioxidants --> free radical induced neuronal damage

Question 54

Dx - EDM

Answer 54

o r/o other dz (CVM/S) o Measure [vitamin E ] in plasma (often normal but damaged occurred early in life) o Usually PME dx

Question 55

Prognosis - EDM

Answer 55

o Poor o Signs may stabilise with high dose vit E tx (alpha tocopherol well absorbed in horses) o Unlikely to be athletic