It’s hard to resist the sweet face of a French bulldog, English bulldog, Boston terrier, Pug or Boxer. Their adorable flat-head, short-nose and corkscrew tails are the epitome of doggie cuteness. But did you know that from the tip of their nose to the end of their curly tail, each of these breeds is prone to Hemivertebrae, the spine deformity in flat-faced dogs?
Why flat-faced, corkscrew tail dogs are at-risk
Hemivertebrae is a congenital deformity of the spine where the left and right halves of the vertebrae grow unequally. This causes individual vertebrae to grow into a “butterfly” shape in what should otherwise be a straight spine. The condition causes the spine to bend and twist or grow at an angle and fuse vertebrae together into a wedge.
While this might sound like an awful condition for a dog, hemivertebrae is NOT considered a medical problem, especially if it only occurs in the tail. The deformity is actually a desired characteristic in brachycephalic breeds (dogs with a flat-face and short-nose) because it’s responsible for their adorable corkscrew tails.
A dog’s tail doesn’t have any spinal cord tissue so when hemivertebrae is bred into that part of the body, it doesn’t cause any mobility problems.
The one caveat is the condition can be painful for puppies during the first 9 months of life as their spine grows.
The real problem with hemivertebrae happens when the deformity affects other parts of your dog’s spine.
While selecting to have hemivertebrae in the tail, it can also cause vertebrae in other parts of the back to fuse into the shape of a wedge. This “wedging effect” doesn’t allow the effected area to connect normally to the healthy parts of the spine. It causes twisting of the bones and puts too much pressure on the spinal cord. This can lead to serious spinal cord compression and paralysis.
The problem is most often seen at the top of a dog’s back from the base of the neck, to the shoulders and the top of the rib cage.
The signs of a spinal cord with too much pressure
Dogs with even a moderate compression on their spine can show signs of:
- Urinary incontinence
- Weakness in their rear legs
- Fecal incontinence
- Paralysis in their hind limbs
Treatment for hemivertebrae
If your brachycephalic breed dog demonstrates any of these symptoms they should be seen immediately by a veterinarian. The longer the nerve supply is compressed, the greater the chance of permanent damage. A veterinarian can confirm the condition with an x-ray and may follow-up with a CT scan, MRI or myelogram. This will determine how badly the spinal cord is compressed.
Some dogs respond well to rest and injections of corticosteroid to reduce the inflammation that is contributing to the pressure. Dogs with more severe spinal compression require surgery to fix the problem.
The surgical procedure is called a Hemilaminectomy. It removes the disc material that is cutting off the flow of blood to the nerves.
The good news is the majority of dogs recover from a spinal cord compression due to hemivertebrae; although the ultimate outcome depends on the severity of the problem. The other good news is that by using responsible breeding practices, dogs have a better chance of maintaining their distinctive corkscrew tails without any health concerns. The best way to do this is to remove a dog who’s passed along hemivertebrae in the spinal cord from the breeding pool.