Imaging diagnosis of sacrocaudal dysgenesis in a shih-tzu dog

A 10-month-old, intact female Shih-tzu dog with a pelvic limb ataxic gait, and urinary and fecal incontinence since birth, was examined by computed tomography and magnetic resonance imaging. The butterfly hemivertebra of the fourth lumbar vertebra, agenesis of the third sacral and coccygeal vertebrae, and spina bifida of the remaining sacral vertebra were observed on the computed tomography images. Magnetic resonance imaging revealed traction of the conus medullaris. The dog was diagnosed with sacrocaudal dysgenesis with presumptive tethered cord syndrome, and concurrent infectious cystitis was found by ultrasonography and urinary analysis. The Shih-tzu recovered from the cystitis, but still has the ataxic gait and urinary and fecal incontinence. This report summarizes the case of a dog with sacrocaudal dysgenesis that was identified by imaging diagnosis.