Cervical stenosis (Wobbler syndrome) in the dog

Cervical stenosis is also known as cervical vertebral instability, spondylopathy or Wobbler syndrome. It is caused by compression of the spinal cord, usually at the base of the neck.

Although compression of the spinal cord occurs in the neck, the hind legs are often the first to be affected. The milder form of cervical stenosis results in unstable gait or running. This form can progress and translate into a wobbly gait (hence the name of the pathology “Wobbler” or wobbly). In severe cases, the dog can suddenly develop total paralysis of all four limbs.

Causes

One or more vertebrae located at the base of the neck (cervical vertebrae) can be deformed or develop instability by subjecting the spinal cord to abnormal pressure. This compression damages the nerves that transmit information to the limbs, consequently causing paresis (weakness) or paralysis of the same.

Initially, pressure affects the dog’s ability to move normally. However, this slight incoordination can be difficult to detect. The lack of coordination, even if slight, can subject the intervertebral discs (which act as shock absorbers) to further stress. In the event that a breakage occurs against the latter, the spinal cord is subjected to sudden and excessive pressure. This can result in the sudden onset of paralysis.

What are the most affected breeds?

The condition mainly affects the Alano and Dobermann breeds, but also Basset Hound, San Bernardo, Bobtail, Borzoi (Russian Greyhound) and Pointers are commonly affected.

There seem to be differences regarding the age of onset of the pathology related to race. For example, in the Great Dane it usually arises at a young age (about 2-3 years), while in Doberman and other breeds in general the signs appear evident around 6-9 years of age.

Diagnosis

Race and clinical signs are good indicators of cervical stenosis. Once the dog is anesthetized or sedated, x-rays of the neck will be performed which will reveal anomalies affecting the vertebrae at the base of the cervical spine. Definitive diagnosis requires performing myelography, computed tomography or magnetic resonance imaging. Myelography is the most commonly performed diagnostic exam. A special radiopaque solution is injected into the fluid surrounding the spinal cord. Afterwards, x-rays of the spine are taken. The compression area is identified by a thinning of the column of the solution in the pressure points.

Treatment

The administration of anti-inflammatory and analgesic drugs can alleviate the initial discomfort, but the greatest probability of success lies in the surgical intervention, especially if performed early in the course of the disease. Although many dogs respond very well to the administration of drugs only, the prolonged and continued use of the latter can lead to unwanted side effects.

It is important to relieve the pressure on the spinal cord as soon as possible. Medical treatment with anti-inflammatory drugs reduces the pressure due to inflammation but is not a solution to the problem if there is a deformed vertebra or disc material that subject the spinal cord to pressure.

There are several surgical techniques that can be used to relieve pressure. If the intervention is performed in the early stages of the disease, before irreversible damage occurs, the outcome can be very good. The surgeon will determine the most appropriate technique for the dog and discuss options, risks and long-term prognosis with the owner.

Most surgeons insist on post-operative hospitalization in the clinic for a few days after the surgery. Once at home, it is important that the dog is helped to walk. He must not be allowed to climb steps or stairs for a period of time. An appropriate physical therapy program specific to the dog will be formulated. The vet will discuss specific home care with the owner.

Can the condition arise again after surgery?

This depends on the specific condition of the dog. In the event that there is an intrinsic weakness in the spine, there is a possibility that the condition will recur. However, thanks to modern surgical techniques, this possibility is not common and most dogs enjoy a relatively normal lifestyle after surgery.