Discospondylitis (alternatively spelled diskospondylitis and often abbreviated as DS) is the most common cause of back pain in middle-aged to older large to giant breed dogs.
DS occurs as the result of an infection of the vertebrae that mostly involves the intervertebral space and the adjacent ends of the vertebral bones (the epiphyses). Bacteria are the most typical microorganisms responsible for DS. Fungal infections are possible but they’re considered far less commonplace. The high cervical, mid thoracic, thoracolumbar, and lumbosacral regions are most commonly involved when the presumably blood-borne pathogen lodges there and seeds the infection.
Though less often observed, the vertebral body itself can be primarily affected by the infection. This distinct disease is referred to as spondylitis or vertebral osteomyelitis to distinguish it from DS.
While the extent to which the predisposition to DS is inherited, it’s generally accepted that there’s a genetic factor influencing its incidence. The presence of one or more genes that may result in a DS-influencing immunosuppression is currently being investigated.
Symptoms and Identification
The clinical signs of DS –– back pain, primarily –– can vary highly in its intensity and are often easily misinterpreted or missed altogether. Stiffness, lameness, or sluggishness are the most obvious symptoms, especially in DS’s earliest phase.
Later on, an impairment of the nervous system, also variable in how it makes itself known, is typically the case. Progressive hind limb weakness and a lack of coordination are common. More rarely, a draining tract or fistula is associated with DS. In this case, the infection becomes visible at the level of the skin adjacent to the affected intervertebral space.
Diagnosis is achieved on the basis of history, clinical signs, signalment (older, large breed males, in particular), and X-rays. Sending X-rays of the spine to a board-certified veterinary radiologist is especially helpful in these cases. Blood cultures are also recommended, but often these will prove unhelpful. It’s for that reason that spinal cultures, affected surgically, are considered the gold standard for effective diagnosis, despite their invasiveness.
Treatment typically relies on long-term antibiotic treatment aimed at the most common microorganisms (Staph aureus) or at those that have been positively cultured. In severe cases, surgery to debride the area and/or relieve the pressure on the spinal cord (caused by the infection and its associated effects) is considered the treatment of choice.
Pain relief is an important aspect of DS treatment that cannot be ignored; more so because most DS cases leave behind a swath of painful osteoarthritis in their wake.
The cost of veterinary care of DS depends on the severity of the disease, how quickly treatment is initiated, the kind of microorganism involved in the infection, and its response to antimicrobial therapy.
In the best of cases, the diagnosis and treatment can be affected for the price of an office visit, X-rays, and medications. For a large breed dog, this will typically run in the low hundreds. However, if veterinary care is sought out or implemented sluggishly, or if the disease defies ready diagnosis (as is often the case), the expense of both diagnostics and treatment can rise precipitously.
$1,000 to $2,500 is considered fairly typical for the average DS patient’s initial care. If one or more surgery is required, however, this range would surely double or triple.
There is no known means of prevention save a judicious breeding protocol that attempts to avoid the use of animals who may carry genetic material predisposing dogs to this disease. For best results, first-degree relatives (parents, siblings, and progeny) should be removed from the breeding pool.
Johnson, R. G., Prata, R. G. Intradiskal osteomyelitis: a conservative approach. Journal of the American Animal Hospital Association1983; 19: 743–750.
Hurov, L., Troy, G., Turnwald, G. Discospondylitis in the dog: 27 cases. Journal of the American Veterinary Medical Association1978; 173: 275–281.
Kornegay, J. N. Diskospondylitis. In: Slatter, D. ed. Textbook of Veterinary Surgery.Philadelphia, W. B. Saunders Co, 1993.
Gilmore, D. R. Lumbosacral discospondylitis in 21 dogs. Journal of the American Animal Hospital Association1987; 23: 57–61.