Extrusão de disco intervertebral intradural em um cão / Intradural disc extrusion in a dog

ABSTRACT

Background: Intervertebral disc extrusion is an important cause of spinal cord dysfunction in dogs. Intradural localizationof the extruded disc material is rare, and is generally associated with a traumatic event or with recurrence of disc extrusionat a previously affected site. We report the clinical presentation, diagnostic workup, and treatment of a dog with intraduralintervertebral disc extrusion not preceded by a traumatic event.Case A 6-year-old male Dachshund was referred for neurological evaluation due to acute onset of hind-end paralysispreceded by claudication of the left hindlimb. The patient had been receiving conservative treatment to no effect. Neurological examination revealed asymmetric non-ambulatory paraparesis, absence of postural reactions and decreased muscletone in both hindlimbs, a bilaterally diminished patellar reflex, and a hindlimb withdrawal reflex which was normal onthe right and greatly diminished to absent on the left. The lower back was tender to epaxial palpation. Plain radiographsof the lumbar spine in the lateral projection showed calcified material within the spinal canal between the third and fourthlumbar vertebrae. Myelography was suggestively abnormal at the same level, with epidural leakage of contrast at L3-L4.Considering the clinical history, breed, age, neurological signs, and radiographic findings, intervertebral disc disease wassuspected despite the inconclusive myelography findings. A dorsolateral lumbar hemilaminectomy was performed. Intraoperatively, the diagnosis was confirmed by visualization of a discolored spinal cord and absence of extradural material.The intradural space was accessed via durotomy. A firm, straw-yellow material was seen compressing the spinal cord andremoved. Subsequent histopathological...