Prevalence of spinous process impingement in thoracic vertebrae on radiographs of clinically-unaffected dogs.

OBJECTIVES: To assess the prevalence of impinged spinous processes in asymptomatic dogs.

METHODS: One hundred and ninety lateral thoracic radiographs of asymptomatic dogs radiographed for reasons other than spinal pain, were retrospectively reviewed by two board-certified radiologists. Images were assessed for impinged spinous processes and graded for narrowing, sclerosis or remodelling of the spinous processes.

RESULTS: The prevalence of impinged spinous processes in unaffected dogs was 33·2%. Seventy-five of 79 (95%) lesions were located between T8 and T11. Impingement of the spinous processes was more common in older dogs and larger dogs displayed more frequent and more severe impingement of the spinous processes compared with smaller breeds.

CLINICAL SIGNIFICANCE: Spinous process impingement is common in animals with no history of spinal pain, indicating that this radiographic finding should be interpreted with caution.