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A 9-year-old spayed female Greyhound that was nonambulatory was examined because of painful progressive paraparesis of 1 week’s duration. No precipitating cause had been identified by the owner. Findings on initial CBC and serum biochemical analysis were unremarkable. Physical examination findings were unremarkable. Neurologic assessment revealed paraparesis with absent conscious proprioception in both pelvic limbs and normal spinal reflexes. The cutaneous trunci reflex was absent caudal to L4. Signs of diffuse pain were evident on palpation of the cranial lumbar region. The lesion was localized to the T3-L3 spinal cord segment. Survey radiography of the lumbar portion of the vertebral column revealed mineralization of several intervertebral disks and narrowing of the intervertebral disk space at L1-2. Magnetic resonance imaging (MRI) of the lumbar vertebral column was performed under general anesthesia (Figure 1)