Intraaxial spinal cord hemorrhage secondary to atlantoaxial subluxation in a dog

A 1-year-old, 3.5-kg, spayed female, toy poodle was presented for acute-onset tetraplegia and neck pain. Neuroanatomical diagnosis was consistent with a first through fifth cervical (C(1) through C(5)) spinal cord lesion. Radiographs of the cervical vertebral column revealed atlantoaxial (AA) subluxation. Magnetic resonance imaging revealed abnormalities consistent with intraaxial spinal cord hemorrhage at the level of the AA articulation. The dog was treated with external coaptation. After 8 days, the dog regained voluntary motor function in all four limbs. Surgical stabilization was pursued. Postoperatively, the dog regained the ability to ambulate. This report details the imaging findings and management of a dog with intraaxial spinal cord hemorrhage secondary to AA subluxation.