Acute paralysis accounts for up to 50% of the caseload at North Florida Neurology.  While disc herniation is a common cause in many of our patients, several other neurological conditions outlined below may present in a similar manner and deserve consideration.

Neoplastic disease (cancer).  Advanced forms of imaging such as CT, MRI or myelography are required to confirm suspicions of a destructive process since plain radiographs are frequently normal.

A CT (near right) shows an osteosarcoma of a thoracic vertebral body.  A normal vertebral body is shown for comparison (far right).

Meningo-myelitis is also a common cause of paralysis in dogs.  Granulomatous meningomyelitis (GME) is the most common inflammatory disease.  It is typically seen in young, small breed dogs.  The same dogs prone to disc disease.

CSF Analysis & advanced imaging (CT, MRI & myelography) are FUNDAMENTAL diagnostic procedures in the evaluation of paralyzed animals.  The results of these tests form the foundation for directing appropriate therapy. Spinal fluid cytology from a dog with GME is shown (right).

Misdiagnosis can lead to unnecessary procedures, including surgery.

Discospondylitis is seen most frequently in the larger breed dogs.  It can lead to pain and acute paralysis.  Survey spinal radiographs can be diagnostic, however CT and MRI may be required in animals with extensive spondylosis. 

Spondylosis deformans, a common degenerative process, may obscure the correct interpretation of  discospondylitis on plain radiographs.  The MRI (right) shows discosondylitis of the lumbosacral junction in a German Shepherd with acute paralysis.

Herniation of intervertebral discs is a major cause of paralysis in dogs.  With the availability of onsite CT imaging, myelography is rarely needed in many of the common breeds of dogs with disc protrusions. 

CT imaging is used to obtain the diagnosis and localize the lesion in many dogs such as Dachshunds, Pekingese and Poodles. 

The CT scans (right) show calcified disc material in the spinal canal (near right) and a normal disc space and spinal canal for comparison (far right).

Vascular Injury to the spinal cord from fibrocartilaginous emboli (spinal infarct) can lead to paralysis or monoparesis (weakness of one leg), most often in mid to large breed dogs.  Myelography, CT myelography or MRI, in conjunction with CSF analysis, is indicated to exclude inflammatory or compressive lesions.