Cervical arthroplasty in two dogs with disk-associated cervical spondylomyelopathy

Abstract

A 4-year-old sexually intact male Doberman Pinscher (dog 1) was evaluated for signs of recurrent cervical pain and ataxia, and a 12-year-old neutered male mixed-breed dog (dog 2) was evaluated for a 4-month history of ataxia and tetraparesis. Examination via magnetic resonance imaging (MRI) revealed spinal cord compression due to disk-associated cervical spondylomyelopathy at C6-7 in dog 1 and at C5-6 in dog 2. Both dogs were surgically treated with a ventral slot procedure and spinal cord decompression, followed by insertion of a titanium cervical disk prosthesis at the affected site. Evaluation of radiographs obtained immediately after surgery indicated that each prosthesis was appropriately placed and provided adequate distraction. Radiographic and neurologic evaluations were performed 2 weeks and 3, 6, and 12 months after surgery in both dogs and 18 months after surgery in dog 1. Distraction of the vertebral bodies decreased moderately over time in both dogs. Intervertebral mobility determined via radiographic assessment of the prosthetic disk during neutral positioning, flexion, and traction of the cervical vertebral column was lost over time in dog 1 and was not achieved in dog 2. Eighteen months after surgery, results of MRI in dog 1 indicated adequate spinal cord decompression with no degeneration in other cervical disks. Cervical arthroplasty was well tolerated with no complications, and outcome was excellent in both dogs; prosthesis presence did not affect ability to reassess the area via MRI. Studies of cervical arthroplasty in dogs with disk-associated cervical spondylomyelopathy are warranted.