9/23 - Chronic Progressive Spinal Disease

Ataxia

What term describes a neurological gait, including incoordination or loss of balance due to weakness or poor muscle control?

Vestibular

What type of ataxia is due to dysfunction of the reflex pathways of the vestibular system that maintains eye, head, and body position?

Cerebellar

What type of ataxia occurs due to failure to integrate multimodal neural information to ensure movements are smooth and adjusted in a timely fashion?

Proprioceptive

What type of ataxia occurs due to loss of proprioceptive information from proprioceptors (muscle spindles, ligament, joint receptors)? There will be truncal sway/wobbles, abnormal stance, circumduction, abduction, adduction, crossing limbs when walking but not crossing them when turning, and other variable issues. There is a tendency to fail while turning and may be hypermetria (over-reaching).

Spondylomyelopathy

Cervical what condition is also called wobblers syndrome and can be disc-associated or osseous-associated? Primary factors include vertebral canal stenosis, vertebral body malformation, vertebral instability, and articular facet malformation. Secondary factors include intervertebral disc failure, hypertrophic ligamentum flavum, osteoarthritis, spinal cord atrophy, and domino lesions. Surgery provides 80% short-term success but 25% will represent within three years and die within 2 years from other concurrent diseases. Surgery includes direct access decompression or distraction fusion.

Ventral Decompression

What surgical procedure treatment for cervical spondylomyelopathy is indicated by persistent cervical pain and nerve root signature, or neurological defects? It involves removal of the torn annulus from the vertebral canal via a ventral slot. After surgery, you can reduce over-nutrition with diet, rest for 6 weeks, provide NSAIDs/gabapentin, provide corticosteroids, and do physiotherapy.

Cervical

Disc disease in what spinal region will produce neck pain, nerve root signature (C5-T2), ataxia in pelvic or all limbs, paresis in pelvic or all limbs, UMN in all limbs or LMN in thoracic and UMN in pelvic limbs, and variable Horner syndrome?

Myelopathy

Degenerative what condition requires neurolocalization to the T3-L3 region, and later becomes more widespread? It is found in older dogs and is slowly progressive, with non-painful pelvic ataxia/paresis at first. Animals are usually over 7 years, and it is found in boxers, german shepherds, and other breeds. Presentation is non-painful and usually asymmetrical. There is progressive axonal degeneration and demyelination of white matter, associated with SOD1 protein misfolding and aggregation. There will also be mitochondrial dysfunction, neuroinflammation, and impaired axonal transport. It is similar to human ALS. Diagnosis is with an older dog with slowly progressive non-painful T3-L3 signs and SOD1 genotype, though MRI will be normal and is done to rule out other problems. Histopathology is the definitive diagnosis. Management is with support and physiotherapy, there is no treatment.

SOD1

Genetic testing for what gene/protein is used to determine an animal’s risk for degenerative myelopathy, but is not diagnostic? The E40K version is most commonly associated, and is an autosomal recessive gene. Two copies puts an animal at risk but not all develop it.

Histopathology

What is the only definitive diagnostic for degenerative myelopathy?

Diverticulum

A spinal arachnoid what structure/malformation is a CSF-filled dilation of the arachnoid space that causes chronic, progressive compression of the spinal cord? It can be primary/congenital or secondary.

Hemivertebrae

What spinal malformation refers to failure of development of one half of the vertebrae? It can be dorsal (kyphosis), lateral (scoliosis), or ventral (lordosis). It can be incidental or can cause myelopathy due to primary spinal canal stenosis (presents under a year old) or accelerated degeneration of intervertebral discs with herniation and further stenosis (presents after 5 years old). It can be associated with both forms of spinal arachnoid diverticulum at any age. It is stabilized with surgery.

Pug

Caudal articular facet hypoplasia, also called what breed myelopathy, involves increased mobility resulting in secondary degenerative changes at the disc and joint, resulting in chronic compressive myelopathy?

Butterfly

What type of vertebrae involves failure of fusion of the lateral halves of the vertebral body due to persistent notochordal tissue between them? It is often incidental and can be usual in bulldog breeds.

Block

What type of vertebrae involves failure of separation of two or more adjacent vertebral bodies? They are usually incidental.

Transitional

What type of vertebrae have indeterminate characteristics and features of vertebrae from adjacent vertebral segments? They usually occur between segments: atlanto-occipital (fusion, additional bone), cervicothoracic (cervical rib), thoracolumbar (lumbar rib), lumbosacral (transitional vertebra - most common).