A dog's spine is made up of numerous small
bones called vertebrae. These extend from
the base of the skull all the way to the end
of the tail. The vertebrae are
interconnected by flexible discs of
cartilage - the intervertebral discs. These
discs provide cushioning between each bone
and permit the neck, spine, and tail to
bend, allowing changes in position and
posture. Above the discs and running through
the bony vertebrae is the spinal cord, which
is made up of a mass of nerve fibers that
run back and forth between the brain and the
rest of the body.
What is
diskospondylitis?
Diskospondylitis (also spelled 'discospondylitis',
and termed vertebral osteomyelitis') is a
bacterial or fungal infection of the
vertebrae and the intervertebral discs in
dogs. The resulting swelling,
inflammation and bone deformities
seen in diskospondylitis put pressure or
compression on the spinal cord which runs
through the vertebrae. The disease is termed
"spondylitis" when only the vertebrae are
involved. The disease should not be confused
with 'spondyl
osis,' which is a
non-infectious fusion or degeneration of the
vertebrae.
What causes
diskospondylitis?
Diskospondylitis seems to occur most
commonly in areas of the country that have a
problem with plant awns (e.g., grass seeds,
fox tails). It is thought that bacteria or
fungi on the awns enter the blood system
when the awns pierce the skin. Bacterial
endocarditis, urinary tract infections, or
dental disease/extractions may be another
means by which bacteria enter the
bloodstream and infect the vertebrae.
Brucella canis has also been
found to cause the disease in dogs.
What are the
symptoms of diskospondylitis?
Common symptoms of this disease include
weight loss, lack of appetite, depression,
fever, and back pain. Dogs with this disease
are generally reluctant to run or jump.
How is
diskospondylitis diagnosed?
Diagnosis of diskospondylitis can be
difficult. Blood tests,
urinalysis, radiographs (x-rays), and
spinal taps may be necessary to diagnose the
disease.
Cultures of blood and urine are
often performed to help isolate the cause
and choose the appropriate treatment.
Myelography may be indicated to
determine the exact location of spinal
compression. Surgery may be needed to reduce
the compression on the spinal cord.
How is
diskospondylitis treated?
Treatment is based on finding the
causative agent - fungal or bacterial.
Because bone infections are difficult to
treat, therapy lasts at least six weeks and
may continue for six months or more. Taking
radiographs at regular intervals during
treatment helps monitor the progress. The
lesions seen early in the disease should
resolve with treatment.
Clinical improvement (lessening of
symptoms) usually occurs within two weeks of
starting treatment. Pain medication may be
needed early in treatment. Exercise
restriction may help decrease the pain also.
The prognosis depends on the ability to
eliminate the infection and on how much
nerve damage resulted from the spinal
compression.
