What is the Association Between Congenital Vertebral Malformations and Disc Herniation in French Bulldogs?
What do you remember about congenital vertebra? If your answer is “not much”, read on for a quick refresher before we dive into a recent study evaluating a correlation between congenital vertebra and disc herniations in Frenchie’s. If your answer is “I got this” then skip to the RESULTS part and start there!
Review
When we look at vertebra we categorize congenital malformations as either defects in segmentation or defects in body formation. An example of a segmentation defect is a block vertebra which happens when two vertebras fuse together and don’t leave space for a disc between. An example of a body defect is a hemivertebra in which part of the vertebra simply didn’t form. A few other options for abnormalities include transitional vertebra or vertebral hypoplasia. Transitional vertebra occur at the junction between two spinal cord regions (ex: thoracic and lumbar) and have characteristics of both (ex: a rib on one side and a lateral process on the other side of the same vertebra). Personally, I consider hypoplasia a variant of body formation dysfunction but technically, articular process hypoplasia is not part of the body of the vertebra and therefore it can be classified as its own malformation.
More congenital vertebra defects occur in the thoracic spine but can occur anywhere along the spine. While they are present at birth, clinical signs may not develop until up to age 2. Some studies suggest signs can even develop beyond that, but it is debated.
Results
· 62 Frenchies enrolled, ages 1.7 to 12 years old
· Neurologic abnormalities: 50 dogs
· Congenital malformations identified in 57 dogs, 100% had hemivertebra, 35% had transitional vertebra and 1.8% had articular process dysplasia.
o 45 dogs had congenital vertebral abnormalities AND neurologic signs.
· Intervertebral disc disease (IVDD) was diagnosed in 58 of 62 dogs (93.5%), however only 49 dogs had concurrent clinical neurologic abnormalities (85%). Many of these dogs had multiple disc herniations.
· In this study, dogs with congenital vertebral malformations were significantly more likely to develop neurologic signs than those without congenital vertebral malformations. HOWEVER, this should be interpreted carefully because this was a small sample and the vast majority of dogs had neurologic signs. This makes not having signs a small sample size.
Previous studies have not found a correlation between congenital vertebral malformations and the development of IVDD. This is the first study to link an association. This could be because of such a high percentage of dogs with clinical signs, the study population or perhaps because we are breeding for specific characteristics in this breed that has increased the incidence of IVDD, congenital vertebral malformations and spinal cord compression.
Take away
What do we take away from this? I think it’s a stretch to tell Frenchie owners that their dog with neurologic disease “shouldn’t worry about it because it’s normal”. Neurologic deficits are not normal even if they are common. You’d never tell an Australian Shepherd owner that seizures are normal, and ignore it, even though that disease is common in that breed! That said, non-progressive neurologic signs in a French Bulldog causes minimal alarm. It’s worth noting in the record, and monitoring, but not necessarily treating. If it progresses, referral for imaging is highly recommended.
Thanks for reading! I hope you have a great week and are enjoying these last glorious summer days! (Or winter days if you’re a southern hemisphere reader.)
Reference: Dimitrievski B, Javor A, et al. Acta Veterinaria-Beograd 2026, 76 (2), 185-201.