Haemorrhagic myelopathy causing acute post-operative paralysis in a rabbit (Oryctolagus cuniculus) with a congenital...

A 7-month-old mixed-breed lionhead entire female rabbit, presented for ovariohysterectomy, displayed a mild bilateral hind limb paresis with external rotation of the hip joints, associated with grade 1/5 pododermatitis of the hind limbs. Investigations were declined by the owner prior to surgery. After a seemingly uncomplicated ovariohysterectomy, the rabbit displayed an acute rapidly progressive bilateral hind limb paralysis with retention of nociception and mild right forelimb paresis. A recheck complete neurologic examination on the following day showed paralysis of the hind limbs without nociception. Post-operative vertebral column radiographs under sedation revealed thoracic lordosis, presumably congenital. Differential diagnoses for paralysis included vascular disease, alteration of the site of congenital vertebral anomaly by perioperative manipulations or iatrogenic medullary injection. Due to the presumed poor prognosis associated with the severity of clinical signs, humane euthanasia was elected. Post mortem magnetic resonance imaging and histopathological examination revealed extensive acute thoracolumbar haemorrhagic myelopathy. Using a comparative medicine approach, a similar complication is reported in children with thoracolumbar vertebral malformation and in horses after general anaesthesia in dorsal recumbency. To the authors' knowledge, this is the first report of non-experimental haemorrhagic myelopathy in a rabbit. Veterinarians should consider this potential complication in rabbits presenting with thoracolumbar lordosis.