Anomalous and other myelopathies Flashcards
Hemivertebrae definition
- Vertebral body fails to form appropriately
Examples of hemivertebrae
- Kyphosis, lordosis, scoliosis
Which vertebra is most commonly affected as a hemivertebrae?
- T8
Appearance of hemivertebrae?
- Wedge-shaped
Which dog breeds get hemivertebrae?
- Dog breeds with screw tails
Neuro signs for hemivertebrae?
- Deferrable to neurolocalization of the anomaly (e.g. a T8 issue will localize to T3-L3)
Definition of a blocked vertebrae?
- Failure of segregation of individual vertebrae
- FUSED vertebrae
Spina bifida definition
- WHen the dorsal aspect of the vertebra doesn’t fuse
Who gets spina bifida?
- English bulldogs and Manx cats
What are transitional vertebrae?
- Vertebra with characteristics of two different types of vertebra (e.g. thoracic and lumbar vertebrae)
Pathophysiology of atlanto-axial instability
- Hypoplasia of the dnes leads to instability of the AA joint
- Axis subluxates or luxates dorsally leading to cord compression
Which ligaments help stabilize the atlanto-axial joint?
- Alar ligaments
- Apical ligaments
- Transverse ligaments
- Maybe draw them on the atlas
History with AA instability
- Acute onset cervical related signs
- Can be the result of traumatic injury (dens fracture)
Signalment of AA instability
- Younger patients, toy breeds (Yorkie, Mini Poodle)
- Can see in older patients
Treatment of AA instability
- 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
Surgery for AA instability
- Similar to Wobblers
- Stabilizing the spine
Subarachnoid diverticulum - where is it?
- 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
Three layers of the meninges
- Dura
- Arachnoid
- Pia
Are subarachnoid diverticula cysts?
- No
- They are not lined with epithelium
Underlying cause of subarachnoid diverticulum
- Only 21% have an underlying cause
Where do subarachnoid diverticula tend to happen, and in which breeds?
- Cervical (Rottweilers)
- Thoracolumbar (Pugs)
- Often dorsal or dorsolaterally
Chronicity of subarachnoid diverticula
- Slow, progressive ataxia and paresis
- Tetra or para depending on the location of the lesion
CLinical signs of subarachnoid diverticula
- Slow, progressive ataxia and paresis
- Tetra or paraparesis depending on the location of the lesion
- Tends to be non-painful
Diagnosis of subarachnoid diverticula
- Best with MRI
- CSF done to rule out predisposing causes
Spondylosis deformans definition
- Common degenerative process with bony bridge between vertebrae
Clinical significance of spondylosis deformans
- Usually none
What are spondylosis deformans usually associated with?
- IVD protrusions
- Tends to develop as a secondary process in attempts to stabilize the disc space due to annular degeneration
Clinical significance of hemivertebrae
- Often none
What is disseminate idiopathic skeletal hyperostosis?
- Extensive periarticular calcification and ossification
- Systemic disorder with bone deposited along tendons, joints, etc.
- More than 4 vertebral bodies joined together
Who gets disseminate idiopathic skeletal hyperostosis?
- Boxers and flat-coated Retrievers are predisposed
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
- T3-L3
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
- Anomaly
- Trauma
- Neoplasia
