Diskospondylitis is an infection of the vertebral disk, most commonly by an infection in the bloodstream. The original infection may involve the heart (endocarditis), teeth, urinary tract or other sites. Bacteria causing infection in these other body systems will enter the bloodstream and cause infection of the intervertebral discs. The most common bacteria causing diskospondylitis is Staphylococcus, although many other bacteria and a few fungi can also be responsible.

A less common cause of disc infection is via a migrating foreign body, such as a grass awn. Grass awns have barbed ends that allow them to migrate forward through body tissues. Wheat, barley, and foxtails are examples of grasses that have this characteristic. The exact portal of entry for these grass awns is not known; however, there are several theories. Inhalation of the grass awn, and migration through the lungs, along the diaphragm, and finally to the spine is the most commonly suggested route of entry.

Previous trauma to the disc or to the vertebrae has also been suggested to play a role in the development of diskospondylitis. Diskospondylitis has also been reported as a complication after spinal surgery.

Clinical signs of pain, reluctance to stand or jump, poor appetite, fever, or spinal cord dysfunction is highly suggestive of diskospondylitis, however, other diseases may cause similar signs, such as:

Trauma to the spine

Meningomyelitis (inflammation of the spinal cord and the membranes)

Neoplasia (cancer)

Intervertebral disk disease (a rupture of a disc, with no infection)

Most dogs with diskospondylitis and minimal neurologic problems respond to appropriate medical therapy. Recurrence is always a possibility, especially in patients with compromised immune systems. For dogs who develop significant neurologic problems, the prognosis is guarded, but some of these patients do respond favorably, so treatment should be attempted.