The dog’s spine is made up of numerous small bones called vertebrae. These extend from the base of the skull all the way to the end of the tail. The vertebrae are interconnected by flexible discs made of cartilage - the intervertebral disc. These discs provide cushioning between each bone and permit the neck, spine, and tail to bend, allowing changes in position and posture. Above the discs and running through the bony vertebrae is the spinal cord, which is made up of a mass of nerve fibers that run back and forth between the brain and the rest of the body.

What is intervertebral disc disease?

As a disc becomes weaker with age or trauma, it may rupture, or herniate, causing a portion of the disc to protrude upward and place pressure on the spinal cord. This pressure typically prevents or inhibits nerve transmission along the spinal cord. The effect on the spinal cord will depend on the amount and severity of the pressure. Effects can include pain, weakness, and paralysis. The location of the 'ruptured disc' will also affect the cord. A disc herniation in the neck area may affect the entire body, while one in the middle of the dog’s back may only affect the actions of the rear legs and abdominal organs.

Dog with very long backs, such as dachshunds and Basset Hounds, understandably have a greater incidence of disc disease in the middle of the back. In fact, This is the area most often affected in all dogs, regardless of the length of the dog’s back. It seems that this area formed at the union of the chest and abdomen, suffers from the greatest amount of torsional stress and is more prone to injury.

In most cases, we never find exactly when or what caused the disc to rupture. Surprisingly, this injury is rarely associated with severe trauma such as being hit by a car or falling from heights. In the smaller breeds, many believe it occurs when these dogs jump down off furniture.

Symptoms

When a disc first ruptures, it causes intense pain. When this occurs in the middle of the back, the dog will arch his back up in pain. When the herniation takes place in the neck, the dog is unwilling to turn his head, and may not even want to lower it to eat and drink. Some dogs will shiver from the pain and walk very carefully and slowly. In severe herniations, the back legs will be partially or completely paralyzed. This may be temporary or permanent. The nerves affecting the bladder and colon may also be affected making it difficult for the dog to urinate or defecate on it’s own. This can obviously be a very serious condition and it is imperative that you seek veterinary care immediately.

Treatment

Treatment almost always includes the use of anti-inflammatory medications such as cortisone (a steroid). These products help shrink the herniated disc and swollen tissue, and at the same time relieve any inflammation that may have occurred within the spinal cord. Pain medication may also be prescribed. Do not use pain relievers without consulting first with your veterinarian. Today more than 90% of all ruptured disc cases in this area of the back are handled with medical therapy alone.

Surgery to either remove the protruding disc material or cut away a portion of the bone that surrounds the spinal cord is sometimes necessary. To be effective, however, surgery must usually be done within the first day or so following the injury. Whether medical, surgical or a combination of the two treatments is used, it may be several weeks before the actual outcome of the case can be determined.

Long term prevention

It may take months before affected dogs heal completely. Restricting jumping activities is very important in preventing reoccurrence. Using a glucosamine and chondroitin product supplement is also highly recommended to help speed recovery and strengthen the damaged cartilage.