Prevalence of thoracic vertebral malformations in French bulldogs, Pugs and English bulldogs with and without associated neurological deficits

R Ryan,R Gutierrez-Quintana,G Ter Haar,Steven De Decker

doi:10.1016/j.tvjl.2017.01.018

R Ryan, R Gutierrez-Quintana + Show 2 more

Open Access

https://doi.org/10.1016/j.tvjl.2017.01.018

Copy DOI

Abstract

Congenital vertebral malformations are common incidental findings in small breed dogs. This retrospective observational study evaluated the type and prevalence of thoracic vertebral malformations in 171 neurologically normal and 10 neurologically abnormal screw-tailed brachycephalic dogs. Neurologically normal dogs underwent CT for reasons unrelated to spinal disease, while affected dogs underwent MRI. Imaging studies were reviewed and vertebral malformations including hemivertebrae, block vertebrae, transitional vertebrae, and spina bifida were documented.The group of clinically normal dogs consisted of 62 French bulldogs, 68 Pugs and 41 English bulldogs. The group of affected dogs consisted of one French bulldog and nine Pugs. Overall, 80.7% of neurologically normal animals were affected by at least one vertebral malformation. There was a significant influence of breed, with thoracic vertebral malformations occurring more often in neurologically normal French bulldogs (P < 0.0001) and English bulldogs (P = 0.002). Compared to other breeds, hemivertebrae occurred more often in neurologically normal French bulldogs (93.5%; P < 0.0001 vs. Pugs; P = 0.004 vs. English bulldogs) and less often in neurologically normal Pugs (17.6%; P = 0.004 vs. English bulldogs). Neurologically normal Pugs were more often diagnosed with transitional vertebrae and spina bifida compared to other breeds (P < 0.0001 for both malformations). Of Pugs included in the study, 4.7% were diagnosed with clinically relevant thoracic vertebral malformations. When compared to the general veterinary hospital population, this was significantly more than the other two breeds (P = 0.006). This study indicates that thoracic vertebral malformations occur commonly in neurologically normal screw-tailed brachycephalic dogs. While hemivertebrae are often interpreted as incidental diagnostic findings, they appear to be of greater clinical importance in Pugs compared to other screw-tailed brachycephalic breeds.

Highlights

Congenital vertebral malformations are common incidental findings in small brachycephalic dogs
The development of clinical signs in dogs with congenital vertebral body malformations is thought to be multifactorial in aetiology, it has been suggested that spinal kyphosis is a key factor in the development of clinical signs and that kyphosis needs to reach a threshold point before clinical signs are likely to occur (Moissonnier et al, 2014; Guevar et al, 2014)
This situation is well recognised for French bulldogs (Moissonnier et al, 2011), it is currently unknown if other screw-tailed brachycephalic dogs demonstrate a similar prevalence of clinically irrelevant thoracic vertebral malformations

Summary

Introduction

Congenital vertebral malformations are common incidental findings in small brachycephalic dogs. The development of clinical signs in dogs with congenital vertebral body malformations is thought to be multifactorial in aetiology, it has been suggested that spinal kyphosis is a key factor in the development of clinical signs and that kyphosis needs to reach a threshold point before clinical signs are likely to occur (Moissonnier et al, 2014; Guevar et al, 2014) This situation is well recognised for French bulldogs (Moissonnier et al, 2011), it is currently unknown if other screw-tailed brachycephalic dogs demonstrate a similar prevalence of clinically irrelevant thoracic vertebral malformations

Objectives

Methods

Results

Discussion

Conclusion