Scoliosis, a curvature of the spine, is most often attributed to congenital vertebral malformations, possibly associated with malposition of the fetus in the uterus. However, researchers have linked cases of acquired scoliosis presented at Cornell University to migration of a parasite only recently reported in horses. Amy Johnson, DVM, a resident in Large Animal Internal Medicine at Cornell, discussed this issue at the 2008 American Association of Equine Practitioners convention, held Dec. 6-10 in San Diego, Calif.

The cases Johnson discussed included four affected horses and a Miniature Donkey that were stabled on different farms in New York state. These equids ranged in age from 6 months to 9 years, and each had acute onset scoliosis that developed suddenly. The C-shaped scoliosis occurred in the neck vertebrae of the horses, while the donkey’s deformation occurred in the middle thoracic spine. Three of the horses were euthanized, while one horse and the donkey were discharged. The discharged horse, a 6-month-old filly, was still alive 2.5 years later, but showed no improvement.


Scoliosis of neck vertebrae

A 6-month-old Arabian filly with acute onset scoliosis. She has survived, but has not shown improvement.

None of the cases were associated with trauma, and veterinarians did not identify any evidence of trauma or fractures on radiographs. Once the scoliosis became evident, there appeared to be no further progression of the malform