What is ataxia in dogs?
Ataxia is defined as a state associated with difficulties in coordinating the movements of the animal's limbs, head and/or body.
There are 3 categories of ataxia according to their origin:
- sensory ataxia linked to spinal cord injury,
- vestibular ataxia resulting from lesions present on the nerve pathways of the vestibular apparatus (inner ear of the dog),
- cerebellar ataxia linked to damage to the cerebellum and/or the nerve pathways connected to it.
How does ataxia manifest in dogs?
Ataxia is mainly manifested by disorders of balance, walking, standing, guidance of movements, but depending on whether it is sensory, vestibular or cerebellar ataxia, the symptoms developed by the animal are not quite the same.
In case of sensory ataxia, the dog:
- is systematically affected by a proprioceptive deficit (disturbances in the perception of his body in space). Among these disorders, the dog may, for example, not be able to replace his paw correctly when it is folded towards the ground or take longer to replace it correctly,
- may experience muscle weakness when ataxia is associated with spinal cord compression.
In case of vestibular ataxia, the dog suffers from loss of balance and has a tilted head.Other symptoms may indicate whether the vestibular ataxia is peripheral (arises from a lesion involving the sensory receptors in the inner ear) or central (arises from the central component of the vestibular apparatus located in the brainstem).
Cerebellar ataxia can be recognized by:
- difficulties in coordinating the movements of the head and the four limbs,
- hypermetria, that is to say disorders of the execution of voluntary movements that seem "exaggerated" . This can be seen when, for example, the dog walks by raising its paws excessively,
- intentional tremors,
- no blink at threat.
What causes ataxia in dogs?
In dogs, sensory ataxia may be secondary to:
- a fibrocartilaginous embolism (vascular anomaly of the spinal cord causing neurological disorders),
- herniated disc,
- trauma causing spinal cord injury,
- a tumoral process,
- inflammation of the spinal cord secondary to distemper,
- otitis middle ear,
- an endocrine condition such as hypothyroidism,
- drug poisoning,
- inflammation of brain tissue,
- a degenerative dog disease such as degenerative myelopathy, abiotrophy (or cerebellar degeneration) or lysosomal storage disease,
- a congenital anomaly linked to infection of the mother during gestation by the herpes virus.
Ataxia in dogs: diagnosis and treatment
When the veterinarian receives a dog that shows signs of ataxia, he performs a neurological examination of the animal. The veterinarian generally begins by observing the gait of the animal in order to detect signs of weakness or incoordination. The neurological examination includes performing various proprioception tests and evaluating the animal's postural reflexes.
Depending on the problem suspected by the veterinarian, he will use additional examinations such as:
- a puncture of cerebrospinal fluid,
- a scanner,
- an MRI
- blood serologies,
- a thyroid hormone assay,
- myelography,
- an X-ray of the spine.
The treatment put in place will therefore depend on the cause identified by the veterinarian.