Vertebral process degenerative joint disease
Degenerative joint disease of the vertebral processes/intervertebral synovial joint has been reported several times in the veterinary literature, most commonly in the cervical and thoracolumbar regions of the vertebral column. These cases appear to be independent of other diseases that lead to articular process hypertrophy (e.g., caudal cervical spondylomyelopathy [CCSM]). The theory is that there is malarticulation between the cranial and caudal articular processes with subsequent vertebral instability, which the body tries to reduce through hypertrophy of the articular processes. It is unclear why there is malarticulation, but it might be a congenital malformation.
This condition has been reported most commonly in Shiloh Shepherd dogs and Scottish Deerhounds. The Shiloh Shepherd dogs ranged in age from 3.5 months to 16 months, while the Scottish Deerhounds were older with a reported age range of 3-6 years. In addition to these two breeds, vertebral articular process hypertrophy has been reported in a Great Dane, two German Shepherd dogs, a mixed breed dog and a Cavalier King Charles Spaniel.
Neurological & physical exam
The Scottish Deerhounds all exhibited signs of cervical pain without neurological deficits, while the Shiloh Shepherds and other breeds were typically presented for evaluation of pain, progressive paraparesis, and pelvic limb proprioceptive ataxia. The thoracic limbs may be affected if the lesion occurs in the cervical region.
Articular process hypertrophy/DJD is typically apparent on survey radiographs. Advanced imaging (e.g., MRI, CT, myelography) is recommended to determine the degree of spinal cord compression and to identify other conditions (e.g., CCSM).
Medical management can be attempted, but this condition is typically progressive so medical management will likely fail eventually. Surgery is generally recommended for patients with evidence of spinal cord compression. The Scottish Deerhounds were treated with intervertebral synovial joint injections of triamcinolone (10mg per joint) and lidocaine (20mg per joint), which relieved the neck pain in 8 of 9 dogs.
The prognosis is unclear given the limited number of cases described in the literature. The success rate appears to be good in the limited numbers of patients reported thus far.
- Dewey CW, Krotscheck U, Winegardner K, et al. Vertebral articular process hypertrophy causing spinal cord compression in a Great Dane. Vet Med 1997;May:291-4.
- Kinzel Z, Hein S, Buecker A, et al. Diagnosis and treatment of arthrosis of cervical articular facet joints in Scottish Deerhounds: 9 cases (1998-2002). J Amer Vet Med Assoc 2003;223:1311-5.
- McDonnell JJ, Knowles KE, de Lahunta A, et al. Thoracolumbar spinal cord compression due to vertebral process degenerative joint disease in a family of Shiloh Shepherd dogs. J Vet Intern Med 2003;17:530-7.
- Penderis J, Schwarz T, McConnell JF, et al. Dysplasia of the caudal vertebral articular facets in four dogs: Results of radiographic, myelographic and magnetic resonance imaging investigation. Vet Rec 2005;156:601-5.