Clinical and radiographic assessment of Grade ۵ disseminated Idiopathic Skeletal Hyperostosis in a Khorasani dog

Background: Disseminated idiopathic skeletal hyperostosis (DISH) is a systemic, non-inflammatory condition characterized by excessive bone growth. It involves bony proliferation at the points where tendons and ligaments attach to the vertebrae. New bone formation occurs around the vertebral joints, with mineralization of the surrounding soft tissues. Although the overall prevalence in dogs is reported to be around ۳–۴%, diffuse and advanced forms are rarely documented. Large dog breeds, particularly the Great Dane and Boxer, are usually predisposed; however, this case describes a rare occurrence in a Khorasani dog. Methods: A ۵-year-old intact female Khorasani dog weighing ۳۵ kg was referred to the Veterinary Hospital of Ferdowsi University of Mashhad with a two-month history of decreased appetite and difficulty in movement. On clinical examination, stiffness of the limbs, obvious dysmetria, hypermetria, and severe pain on palpation of the lumbar region were noted. The dog was immediately referred for taking radiographs, and two lateral radiographs were taken from the cervical to the lumbar spine. Results: The radiographic examination showed extensive, continuous ventral ossification along the thoracic and lumbar spine. Complete bony bridges were seen between multiple vertebral bodies, while the intervertebral disc spaces remained intact. The appearance was consistent with Grade ۵ disease, showing the typical undulating ‘flowing candle wax’ pattern along the ventral aspect of the spine. Conclusion: This report describes a severe and widespread case of DISH in a Khorasani dog. Recognizing its radiology features is important for making the correct diagnosis and ruling it out from other causes of spinal abnormalities. Radiography is an easy, practical, and reliable way to evaluate the disease's severity and progression in animals.

کلیدواژه ها:

Radiography ، Diffuse idiopathic skeletal hyperostosis ، Khorsani dog