T9-T10 Intervertebral Disc Herniation in Three Dogs

SummaryThree middle-aged (6-8 years), intact male Dachshunds were admitted to the University of Tennessee Veterinary Teaching Hospital (UTVTH) with acute onset of back pain and pelvic limb paralysis.Physical examination of dog #1 revealed hyperaesthesia of the thoracolumbar spine. Superficial pain sensation was absent in the pelvic limbs, while deep pain sensation was intact. The cutaneous trunci (panniculus) reflex was absent caudal to the thoraco-lumbar region. Reflexes to the pelvic limbs were exaggerated.A myelogram showed dorsal deviation of the ventral contrast column and attenuation of the ventral and dorsal contrast columns at the T9-T10 disc space. A hemilaminectomy was performed from T9 to T10, and mineralized disc material was retrieved from the vertebral canal at T9-T10. The T9- T10 to L3-L4 disc spaces were fenestrated. Two weeks after surgery, superficial and deep pain sensation of the rearlimbs were present, but paralysis persisted. The animal was euthanatised at the owners’ request. A postmortem examination was not performed.Dog #2 displayed absent superficial pain sensation, and intact deep pain sensation of the pelvic limbs. Hyperaesthesia of the thoracolumbar region and hyperreflexia of the rear limbs were noted. Examination of the cutaneous trunci reflex was not performed. A myelogram revealed ventral extradural compression of the spinal cord at T9- T10. A T9-T10 hemilaminectomy revealed a large amount of extruded disc material, which was removed. The Tll- T12 to L4-L5 intervertebral discs were fenestrated. Forty-eight hours postoperatively, the patient regained voluntary motor function, and recovery was uneventful.Neurologic examination of dog #3 revealed absence of deep pain sensation in the pelvic limbs; duration of which was not known. Spinal radiographs and myelography revealed ventral extradural spinal cord compression at T9-T10 (Fig.). A right-sided hemilaminectomy at T9-T10 revealed a large amount of calcified disc material, ventral to the spinal cord. The T11-T12 through Ll- L2 intervertebral discs were fenestrated. Sixty days postoperatively, paralysis persisted and the dog was euthanatised. No postmortem examination was performed.Herniation of the T9-T10 intervertebral disc was diagnosed in three Dachshunds with acute paraplegia. The clinical diagnosis and surgical management of T9-T10 disc herniation are similar to that in the more common sites of disc herniation.