Decompressive surgery for treatment of a dorsal compressive atlantoaxial band causing nonambulatory tetraparesis in three toy-breed dogs

Authors: 
Lee JH, Yoon HY, Kim JH, Han HJ.
J Am Vet Med Assoc. 2019 Sep 15;255(6):700-705.

CASE DESCRIPTION: 3 toy-breed dogs (a 5-year-old Pomeranian, a 12-year-old Pomeranian, and a 13-year-old Yorkshire Terrier) were evaluated because of a sudden onset of nonambulatory tetraparesis.

CLINICAL FINDINGS: In all 3 dogs, MRI revealed a dorsal compressive atlantoaxial (AA) band as the cause of the neurologic deficits. Percentages of dorsal compression of the spinal cord were 28.6%, 31%, and 28.8%.

TREATMENT AND OUTCOME: All 3 dogs underwent decompressive surgery via a dorsal approach. The AA band was removed, and a durotomy was performed, which resulted in spontaneous drainage of a copious amount of CSF. Grossly, the spinal cord parenchyma appeared normal, other than the dorsal compression. To alleviate the AA instability resulting from removal of the dorsal AA ligament, 2-0 polydioxanone was placed in the dorsal cervical muscles extending from the atlantooccipital joint to C2. Postoperatively, all 3 dogs regained normal ambulation between 18 and 30 days after surgery. No complications were reported, and clinical signs did not recur during follow-up times ranging from 4 to 19 months.

CLINICAL RELEVANCE: Findings suggested that surgical treatment may be an effective option in managing dogs with a dorsal compressive AA band causing nonambulatory tetraparesis. Notably, all of the dogs had other craniocervical abnormalities, but none of these abnormalities were considered severe enough to have caused tetraparesis.

Small animal: