Anomalous and other myelopathies

Question 1

Hemivertebrae definition

Answer 1

• Vertebral body fails to form appropriately

Question 2

Examples of hemivertebrae

Answer 2

• Kyphosis, lordosis, scoliosis

Question 3

Which vertebra is most commonly affected as a hemivertebrae?

Answer 3

• T8

Question 4

Appearance of hemivertebrae?

Answer 4

• Wedge-shaped

Question 5

Which dog breeds get hemivertebrae?

Answer 5

• Dog breeds with screw tails

Question 6

Neuro signs for hemivertebrae?

Answer 6

• Deferrable to neurolocalization of the anomaly (e.g. a T8 issue will localize to T3-L3)

Question 7

Definition of a blocked vertebrae?

Answer 7

• Failure of segregation of individual vertebrae

- FUSED vertebrae

Question 8

Spina bifida definition

Answer 8

• WHen the dorsal aspect of the vertebra doesn’t fuse

Question 9

Who gets spina bifida?

Answer 9

• English bulldogs and Manx cats

Question 10

What are transitional vertebrae?

Answer 10

• Vertebra with characteristics of two different types of vertebra (e.g. thoracic and lumbar vertebrae)

Question 11

Pathophysiology of atlanto-axial instability

Answer 11

• Hypoplasia of the dnes leads to instability of the AA joint
• Axis subluxates or luxates dorsally leading to cord compression

Question 12

Which ligaments help stabilize the atlanto-axial joint?

Answer 12

• Alar ligaments
• Apical ligaments
• Transverse ligaments
• Maybe draw them on the atlas

Question 13

History with AA instability

Answer 13

• Acute onset cervical related signs

- Can be the result of traumatic injury (dens fracture)

Question 14

Signalment of AA instability

Answer 14

• Younger patients, toy breeds (Yorkie, Mini Poodle)

- Can see in older patients

Question 15

Treatment of AA instability

Answer 15

• Conservative vs surgical
• Conservative is a bandage and strict rest + pain control
• External coaptation (immobilize the joint above and below)
• Pain control
• 6 weeks at least and strict cage management
• NEVER use a neck lead whether you do or don’t stabilize

Question 16

Surgery for AA instability

Answer 16

• Similar to Wobblers

- Stabilizing the spine

Question 17

Subarachnoid diverticulum - where is it?

Answer 17

• It’s in the subarachnoid space
• Leads to cord compression
• Think that there’s an abnormality in how CSF flows, leading to pockets of inflammation

Question 18

Three layers of the meninges

Answer 18

• Dura
• Arachnoid
• Pia

Question 19

Are subarachnoid diverticula cysts?

Answer 19

• No

- They are not lined with epithelium

Question 20

Underlying cause of subarachnoid diverticulum

Answer 20

• Only 21% have an underlying cause

Question 21

Where do subarachnoid diverticula tend to happen, and in which breeds?

Answer 21

• Cervical (Rottweilers)
• Thoracolumbar (Pugs)
• Often dorsal or dorsolaterally

Question 22

Chronicity of subarachnoid diverticula

Answer 22

• Slow, progressive ataxia and paresis

- Tetra or para depending on the location of the lesion

Question 23

CLinical signs of subarachnoid diverticula

Answer 23

• Slow, progressive ataxia and paresis
• Tetra or paraparesis depending on the location of the lesion
• Tends to be non-painful

Question 24

Diagnosis of subarachnoid diverticula

Answer 24

• Best with MRI

- CSF done to rule out predisposing causes

Question 25

Spondylosis deformans definition

Answer 25

- Common degenerative process with bony bridge between vertebrae

Question 26

Clinical significance of spondylosis deformans

Answer 26

- Usually none

Question 27

What are spondylosis deformans usually associated with?

Answer 27

- IVD protrusions | - Tends to develop as a secondary process in attempts to stabilize the disc space due to annular degeneration

Question 28

Clinical significance of hemivertebrae

Answer 28

- Often none

Question 29

What is disseminate idiopathic skeletal hyperostosis?

Answer 29

- Extensive periarticular calcification and ossification - Systemic disorder with bone deposited along tendons, joints, etc. - More than 4 vertebral bodies joined together

Question 30

Who gets disseminate idiopathic skeletal hyperostosis?

Answer 30

- Boxers and flat-coated Retrievers are predisposed

Question 31

Localization: 6 m/o MN Pitbull Progressive paraparesis for 3 months - Neuro exam: Mentation normal Crouched in rear Proprioception decreased in pelvic limbs Reflexes Normal CN normal

Answer 31

- T3-L3

Question 32

Differentials for Blu 6 m/o MN Pitbull Progressive paraparesis for 3 months - Neuro exam: Mentation normal Crouched in rear Proprioception decreased in pelvic limbs Reflexes Normal CN normal

Answer 32

- Anomaly - Trauma - Neoplasia